TY  - JOUR
AU  - Vojvodić, Snežana
AU  - Dimitrijević, Milena
AU  - Žižić, Milan
AU  - Dučić, Tanja
AU  - AQUILANTI, Giuliana
AU  - Stanić, Marina
AU  - Zechmann, Bernd
AU  - Danilović Luković, Jelena
AU  - Stanković, Dalibor M.
AU  - Opačić, Miloš
AU  - Morina, Arian
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2378
AB  - Metabolism of metals in microalgae and adaptation to metal excess are of significant environmental importance. We report a three-step mechanism that the green microalga Chlorella sorokiniana activates during the acquisition of and adaptation to manganese (Mn), which is both an essential trace metal and a pollutant of waters. In the early stage, Mn2+ was mainly bound to membrane phospholipids and phosphates in released mucilage. The outer cell wall
was reorganized and lipids were accumulated, with a relative increase in lipid saturation. Intracellular redox settings were rapidly altered in the presence of Mn excess, with increased production of reactive oxygen species that resulted in lipid peroxidation and a decrease in the concentration of thiols. In the later stage, Mn2+ was chelated by polyphosphates and accumulated in the cells. The structure of the inner cell wall was modified and the redox milieu established a new balance. Polyphosphates serve as a transient Mn2+ storage ligand, as proposed previously. In the final stage, Mn was stored in multivalent Mn clusters that resemble the structure of the tetramanganese–calcium core of the oxygen-evolving complex. The present findings elucidate the bioinorganic chemistry and metabolism of Mn in microalgae, and may shed new light on water-splitting Mn clusters.
PB  - Oxford University Press
T2  - Journal of Experimental Botany
T1  - A three-step process of manganese acquisition and storage in the microalga Chlorella sorokiniana
EP  - 1122
IS  - 3
SP  - 1107
VL  - 74
DO  - 10.1093/jxb/erac472
ER  - 

@article{
author = "Vojvodić, Snežana and Dimitrijević, Milena and Žižić, Milan and Dučić, Tanja and AQUILANTI, Giuliana and Stanić, Marina and Zechmann, Bernd and Danilović Luković, Jelena and Stanković, Dalibor M. and Opačić, Miloš and Morina, Arian and Pittman, Jon K. and Spasojević, Ivan",
year = "2023",
abstract = "Metabolism of metals in microalgae and adaptation to metal excess are of significant environmental importance. We report a three-step mechanism that the green microalga Chlorella sorokiniana activates during the acquisition of and adaptation to manganese (Mn), which is both an essential trace metal and a pollutant of waters. In the early stage, Mn2+ was mainly bound to membrane phospholipids and phosphates in released mucilage. The outer cell wall
was reorganized and lipids were accumulated, with a relative increase in lipid saturation. Intracellular redox settings were rapidly altered in the presence of Mn excess, with increased production of reactive oxygen species that resulted in lipid peroxidation and a decrease in the concentration of thiols. In the later stage, Mn2+ was chelated by polyphosphates and accumulated in the cells. The structure of the inner cell wall was modified and the redox milieu established a new balance. Polyphosphates serve as a transient Mn2+ storage ligand, as proposed previously. In the final stage, Mn was stored in multivalent Mn clusters that resemble the structure of the tetramanganese–calcium core of the oxygen-evolving complex. The present findings elucidate the bioinorganic chemistry and metabolism of Mn in microalgae, and may shed new light on water-splitting Mn clusters.",
publisher = "Oxford University Press",
journal = "Journal of Experimental Botany",
title = "A three-step process of manganese acquisition and storage in the microalga Chlorella sorokiniana",
pages = "1122-1107",
number = "3",
volume = "74",
doi = "10.1093/jxb/erac472"
}

Vojvodić, S., Dimitrijević, M., Žižić, M., Dučić, T., AQUILANTI, G., Stanić, M., Zechmann, B., Danilović Luković, J., Stanković, D. M., Opačić, M., Morina, A., Pittman, J. K.,& Spasojević, I.. (2023). A three-step process of manganese acquisition and storage in the microalga Chlorella sorokiniana. in Journal of Experimental Botany
Oxford University Press., 74(3), 1107-1122.
https://doi.org/10.1093/jxb/erac472

Vojvodić S, Dimitrijević M, Žižić M, Dučić T, AQUILANTI G, Stanić M, Zechmann B, Danilović Luković J, Stanković DM, Opačić M, Morina A, Pittman JK, Spasojević I. A three-step process of manganese acquisition and storage in the microalga Chlorella sorokiniana. in Journal of Experimental Botany. 2023;74(3):1107-1122.
doi:10.1093/jxb/erac472 .

Vojvodić, Snežana, Dimitrijević, Milena, Žižić, Milan, Dučić, Tanja, AQUILANTI, Giuliana, Stanić, Marina, Zechmann, Bernd, Danilović Luković, Jelena, Stanković, Dalibor M., Opačić, Miloš, Morina, Arian, Pittman, Jon K., Spasojević, Ivan, "A three-step process of manganese acquisition and storage in the microalga Chlorella sorokiniana" in Journal of Experimental Botany, 74, no. 3 (2023):1107-1122,
https://doi.org/10.1093/jxb/erac472 . .

TY  - CONF
AU  - Santrač, Isidora
AU  - Danilović Luković, Jelena
AU  - Dimitrijević, Milena
AU  - Stanić, Marina
AU  - Tanović, Marija
AU  - Ćurić, Valentina
AU  - Kovačević, Snežana
AU  - Zechmann, Bernd
AU  - Žižić, Milan
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/3144
AB  - Haematococcus pluvialis is a unicellular green alga with a complex life cycle and a
remarkable metabolic and structural adaptability that allows it to thrive in metal-infested
environments. H. pluvialis could be potentially used in the remediation of waters polluted
with metals, such as manganese (Mn). Mn is also an essential element involved in different
metabolic processes, such as photosynthesis and antioxidantive defence. Herein, we
examined morphological response of metabolically active green cell type of H. pluvialis
(microzooids) to high Mn concentrations exceeding their physiological quota. When exposed
to 1 mM Mn2+, cell viability remained stable over a 3-day period. Inductively coupled plasma
atomic emission spectroscopy showed the prompt uptake of Mn by the microzooid cells after
1 h of the treatment, with a modest increase of the concentration of Mn in the biomass at 24
h. Scanning electron microscopy revealed granular deposits on microzooid surfaces after 1
hour, likely Mn deposits, while transmission electron microscopy (TEM) micrographs
showed that some cells had wall rupture and degraded intracellular content and damaged
organelles. After 24 and 72 h, a different type of cell morphology emerged, characterized by
thickened cell wall, preserved intracellular compartments, and reduced total area of lipid
droplets. Both cell types exhibited vacuoles containing dark granules, possibly indicative of
Mn accumulations. Quantitative TEM analysis demonstrated that an excess of Mn reduced
cell cross-section and lipid droplet area while increasing vacuole cross-section and cell wall
thickness. The intricate adaptive responses of H. pluvialis to elevated Mn concentrations
exemplified by cell wall thickening, reduction in lipid droplets total area due to increased
energy demand, and the accumulation of Mn in vacuoles, exhibits the impressive structural
adaptability. Further investigation using analytical methods will provide a more profound
understanding of the metabolic dimensions of adaptive response
PB  - UNIVERSITY OF BELGRADE, FACULTY OF TECHNOLOGY AND METALLURGY Karnegijeva 4, Belgrade
C3  - International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia
T1  - Structural adaptibility of Haematococcus pluvialis green phase cells exposed to manganese excess
EP  - 44
SP  - 44
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_3144
ER  - 

@conference{
author = "Santrač, Isidora and Danilović Luković, Jelena and Dimitrijević, Milena and Stanić, Marina and Tanović, Marija and Ćurić, Valentina and Kovačević, Snežana and Zechmann, Bernd and Žižić, Milan and Spasojević, Ivan",
year = "2023",
abstract = "Haematococcus pluvialis is a unicellular green alga with a complex life cycle and a
remarkable metabolic and structural adaptability that allows it to thrive in metal-infested
environments. H. pluvialis could be potentially used in the remediation of waters polluted
with metals, such as manganese (Mn). Mn is also an essential element involved in different
metabolic processes, such as photosynthesis and antioxidantive defence. Herein, we
examined morphological response of metabolically active green cell type of H. pluvialis
(microzooids) to high Mn concentrations exceeding their physiological quota. When exposed
to 1 mM Mn2+, cell viability remained stable over a 3-day period. Inductively coupled plasma
atomic emission spectroscopy showed the prompt uptake of Mn by the microzooid cells after
1 h of the treatment, with a modest increase of the concentration of Mn in the biomass at 24
h. Scanning electron microscopy revealed granular deposits on microzooid surfaces after 1
hour, likely Mn deposits, while transmission electron microscopy (TEM) micrographs
showed that some cells had wall rupture and degraded intracellular content and damaged
organelles. After 24 and 72 h, a different type of cell morphology emerged, characterized by
thickened cell wall, preserved intracellular compartments, and reduced total area of lipid
droplets. Both cell types exhibited vacuoles containing dark granules, possibly indicative of
Mn accumulations. Quantitative TEM analysis demonstrated that an excess of Mn reduced
cell cross-section and lipid droplet area while increasing vacuole cross-section and cell wall
thickness. The intricate adaptive responses of H. pluvialis to elevated Mn concentrations
exemplified by cell wall thickening, reduction in lipid droplets total area due to increased
energy demand, and the accumulation of Mn in vacuoles, exhibits the impressive structural
adaptability. Further investigation using analytical methods will provide a more profound
understanding of the metabolic dimensions of adaptive response",
publisher = "UNIVERSITY OF BELGRADE, FACULTY OF TECHNOLOGY AND METALLURGY Karnegijeva 4, Belgrade",
journal = "International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia",
title = "Structural adaptibility of Haematococcus pluvialis green phase cells exposed to manganese excess",
pages = "44-44",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_3144"
}

Santrač, I., Danilović Luković, J., Dimitrijević, M., Stanić, M., Tanović, M., Ćurić, V., Kovačević, S., Zechmann, B., Žižić, M.,& Spasojević, I.. (2023). Structural adaptibility of Haematococcus pluvialis green phase cells exposed to manganese excess. in International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia
UNIVERSITY OF BELGRADE, FACULTY OF TECHNOLOGY AND METALLURGY Karnegijeva 4, Belgrade., 44-44.
https://hdl.handle.net/21.15107/rcub_rimsi_3144

Santrač I, Danilović Luković J, Dimitrijević M, Stanić M, Tanović M, Ćurić V, Kovačević S, Zechmann B, Žižić M, Spasojević I. Structural adaptibility of Haematococcus pluvialis green phase cells exposed to manganese excess. in International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia. 2023;:44-44.
https://hdl.handle.net/21.15107/rcub_rimsi_3144 .

Santrač, Isidora, Danilović Luković, Jelena, Dimitrijević, Milena, Stanić, Marina, Tanović, Marija, Ćurić, Valentina, Kovačević, Snežana, Zechmann, Bernd, Žižić, Milan, Spasojević, Ivan, "Structural adaptibility of Haematococcus pluvialis green phase cells exposed to manganese excess" in International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia (2023):44-44,
https://hdl.handle.net/21.15107/rcub_rimsi_3144 .

TY  - CONF
AU  - Santrač, Isidora
AU  - Žižić, Milan
AU  - AQUILANTI, Giuliana
AU  - Gianoncelli, Alessandra
AU  - Bonanni, Valentina
AU  - Danilović Luković, Jelena
AU  - Dimitrijević, Milena
AU  - Stanić, Marina
AU  - Tanović, Marija
AU  - Ćurić, Valentina
AU  - Kovačević, Snežana
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/3139
AB  - Haematococcus pluvialis is a unicellular green alga of significant environmental and
economic impact, well adapted to life in extreme conditions such as metal pollution.
Manganese is a common pollutant of water bodies that is related to mining and industrial
drainage, and microalgae have been applied in their bioremediation. To study changes in Mn
redox and coordination form upon interaction with H. pluvialis cells, we exposed late
exponential/early stationary green phase culture to 1 mM MnCl2 (Mn2+) for 72 h. Applied
concentration exceeds microalgal physiological quota but it was non-toxic. Structure of
coordinated Mn in the cells was analyzed using X-ray absorption near edge structure
(XANES) and extended X-ray Absorption Fine Structure (EXAFS) spectroscopy, while
visualization and elemental mapping of Mn was performed by micro X-ray fluorescence
(μXRF). XANES spectra showed that the oxidation form of Mn in H. pluvialis biomass
remained 2+. However, EXAFS showed Mn coordination in microalgae is closer to hydrated
MnSO4 with minor deviation of the local geometry. The shorter Mn-O bonds in biomass,
compared to crystal model, implies somewhat more stable complex in H. pluvialis. This
suggests that H. pluvialis may use sulphated polysaccharides for Mn sequestration, which
would be a newly proposed mechanism of metal coordination and storage. μXRF analysis
showed co-localization of Mn with O and Na, with particularly good superimposition for Mn
and O. O-rich regions may represent vacuoles, filled with organic acids including sulphates,
or starch granules and accumulations of sulphated polysaccharides, which are known to be
produced by H. pluvialis. In addition, vacuoles in plant cells are known to act as sinks for
Na+ ions. These findings are in line with structural analysis that showed dark precipitates in
vacuoles, which are likely accumulations of Mn.
C3  - International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia
T1  - The coordination and storage of manganese in the microalga Haematococcus pluvialis
SP  - 45
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_3139
ER  - 

@conference{
author = "Santrač, Isidora and Žižić, Milan and AQUILANTI, Giuliana and Gianoncelli, Alessandra and Bonanni, Valentina and Danilović Luković, Jelena and Dimitrijević, Milena and Stanić, Marina and Tanović, Marija and Ćurić, Valentina and Kovačević, Snežana and Spasojević, Ivan",
year = "2023",
abstract = "Haematococcus pluvialis is a unicellular green alga of significant environmental and
economic impact, well adapted to life in extreme conditions such as metal pollution.
Manganese is a common pollutant of water bodies that is related to mining and industrial
drainage, and microalgae have been applied in their bioremediation. To study changes in Mn
redox and coordination form upon interaction with H. pluvialis cells, we exposed late
exponential/early stationary green phase culture to 1 mM MnCl2 (Mn2+) for 72 h. Applied
concentration exceeds microalgal physiological quota but it was non-toxic. Structure of
coordinated Mn in the cells was analyzed using X-ray absorption near edge structure
(XANES) and extended X-ray Absorption Fine Structure (EXAFS) spectroscopy, while
visualization and elemental mapping of Mn was performed by micro X-ray fluorescence
(μXRF). XANES spectra showed that the oxidation form of Mn in H. pluvialis biomass
remained 2+. However, EXAFS showed Mn coordination in microalgae is closer to hydrated
MnSO4 with minor deviation of the local geometry. The shorter Mn-O bonds in biomass,
compared to crystal model, implies somewhat more stable complex in H. pluvialis. This
suggests that H. pluvialis may use sulphated polysaccharides for Mn sequestration, which
would be a newly proposed mechanism of metal coordination and storage. μXRF analysis
showed co-localization of Mn with O and Na, with particularly good superimposition for Mn
and O. O-rich regions may represent vacuoles, filled with organic acids including sulphates,
or starch granules and accumulations of sulphated polysaccharides, which are known to be
produced by H. pluvialis. In addition, vacuoles in plant cells are known to act as sinks for
Na+ ions. These findings are in line with structural analysis that showed dark precipitates in
vacuoles, which are likely accumulations of Mn.",
journal = "International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia",
title = "The coordination and storage of manganese in the microalga Haematococcus pluvialis",
pages = "45",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_3139"
}

Santrač, I., Žižić, M., AQUILANTI, G., Gianoncelli, A., Bonanni, V., Danilović Luković, J., Dimitrijević, M., Stanić, M., Tanović, M., Ćurić, V., Kovačević, S.,& Spasojević, I.. (2023). The coordination and storage of manganese in the microalga Haematococcus pluvialis. in International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia, 45.
https://hdl.handle.net/21.15107/rcub_rimsi_3139

Santrač I, Žižić M, AQUILANTI G, Gianoncelli A, Bonanni V, Danilović Luković J, Dimitrijević M, Stanić M, Tanović M, Ćurić V, Kovačević S, Spasojević I. The coordination and storage of manganese in the microalga Haematococcus pluvialis. in International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia. 2023;:45.
https://hdl.handle.net/21.15107/rcub_rimsi_3139 .

Santrač, Isidora, Žižić, Milan, AQUILANTI, Giuliana, Gianoncelli, Alessandra, Bonanni, Valentina, Danilović Luković, Jelena, Dimitrijević, Milena, Stanić, Marina, Tanović, Marija, Ćurić, Valentina, Kovačević, Snežana, Spasojević, Ivan, "The coordination and storage of manganese in the microalga Haematococcus pluvialis" in International Conference on Biochemical Engineering and Biotechnology for Young Scientists, December 7-8th 2023, Belgrade, Serbia (2023):45,
https://hdl.handle.net/21.15107/rcub_rimsi_3139 .

TY  - CONF
AU  - Dimitrijević, Milena
AU  - Kovačević, Snežana
AU  - Jovanović, Uroš
AU  - Stanić, Marina
AU  - Opačić, Miloš
AU  - Santrač, Isidora
AU  - Tanović, Marija
AU  - Ćurić, Valentina
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2421
AB  - Heavy metals remain a major pollutant in waters near mining sites. Water pollution is a current, longterm problem that affects plants and organisms that live in these water systems, and the effect is very harmful not only for individual species and populations, but also for the entire biological community. This study analyzed the potential of the microalga Chlorella sorokiniana in the adsorption of four selected metals: Fe, Cu, Zn and Ni, all present in high amounts in Lake Robule. This pilot study was conducted to evaluate the potential of these microalgae for possible use in future bioremediation treatment of these water. A laboratory study of metal accumulation in lake water samples lasted for 7 days, after which a total decrease in metal concentration was observed, namely Fe ~25%, Cu ~17%, and Zn ~4% on the seventh day. This study confirms the strong potential of microalgae C. sorokiniana to reduce the presence of heavy metals in conditions known for the low pH value of water with a high percentage of Fe and other heavy metals.
PB  - University of Belgrade
PB  - Technical Faculty in Bor
C3  - 30th international conference ecological truth and environmental research – EcoTER’23. 20-23 June 2023, Mt Stara Planina, Serbia
T1  - Application of microalga Chlorella sorokiniana in wastewater bioremediation – case of lake Robule
EP  - 334
SP  - 330
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2421
ER  - 

@conference{
author = "Dimitrijević, Milena and Kovačević, Snežana and Jovanović, Uroš and Stanić, Marina and Opačić, Miloš and Santrač, Isidora and Tanović, Marija and Ćurić, Valentina and Spasojević, Ivan",
year = "2023",
abstract = "Heavy metals remain a major pollutant in waters near mining sites. Water pollution is a current, longterm problem that affects plants and organisms that live in these water systems, and the effect is very harmful not only for individual species and populations, but also for the entire biological community. This study analyzed the potential of the microalga Chlorella sorokiniana in the adsorption of four selected metals: Fe, Cu, Zn and Ni, all present in high amounts in Lake Robule. This pilot study was conducted to evaluate the potential of these microalgae for possible use in future bioremediation treatment of these water. A laboratory study of metal accumulation in lake water samples lasted for 7 days, after which a total decrease in metal concentration was observed, namely Fe ~25%, Cu ~17%, and Zn ~4% on the seventh day. This study confirms the strong potential of microalgae C. sorokiniana to reduce the presence of heavy metals in conditions known for the low pH value of water with a high percentage of Fe and other heavy metals.",
publisher = "University of Belgrade, Technical Faculty in Bor",
journal = "30th international conference ecological truth and environmental research – EcoTER’23. 20-23 June 2023, Mt Stara Planina, Serbia",
title = "Application of microalga Chlorella sorokiniana in wastewater bioremediation – case of lake Robule",
pages = "334-330",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2421"
}

Dimitrijević, M., Kovačević, S., Jovanović, U., Stanić, M., Opačić, M., Santrač, I., Tanović, M., Ćurić, V.,& Spasojević, I.. (2023). Application of microalga Chlorella sorokiniana in wastewater bioremediation – case of lake Robule. in 30th international conference ecological truth and environmental research – EcoTER’23. 20-23 June 2023, Mt Stara Planina, Serbia
University of Belgrade., 330-334.
https://hdl.handle.net/21.15107/rcub_rimsi_2421

Dimitrijević M, Kovačević S, Jovanović U, Stanić M, Opačić M, Santrač I, Tanović M, Ćurić V, Spasojević I. Application of microalga Chlorella sorokiniana in wastewater bioremediation – case of lake Robule. in 30th international conference ecological truth and environmental research – EcoTER’23. 20-23 June 2023, Mt Stara Planina, Serbia. 2023;:330-334.
https://hdl.handle.net/21.15107/rcub_rimsi_2421 .

Dimitrijević, Milena, Kovačević, Snežana, Jovanović, Uroš, Stanić, Marina, Opačić, Miloš, Santrač, Isidora, Tanović, Marija, Ćurić, Valentina, Spasojević, Ivan, "Application of microalga Chlorella sorokiniana in wastewater bioremediation – case of lake Robule" in 30th international conference ecological truth and environmental research – EcoTER’23. 20-23 June 2023, Mt Stara Planina, Serbia (2023):330-334,
https://hdl.handle.net/21.15107/rcub_rimsi_2421 .

TY  - CONF
AU  - Santrač, Isidora
AU  - Dimitrijević, Milena
AU  - Stanić, Marina
AU  - Tanović, Marija
AU  - Ćurić, Valentina
AU  - Kovačević, Snežana
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2416
AB  - Acid mine drainage ponds represents a specific artificial ecosystem that gives advantage to extemophilic microalgae. The mechanisms of adaptaton of such strains to excess metal concentrations that are common for their habitat, are poorly understood. Herein, we analzyed two strains of the green microalga Chlamydomonas acidophila - 137 and PM01, which have been isolated from different mining sites, for their interactions with Mn ions. The effects of different concentrations of Mn2+ were investigated in the late exponential/early stationary phase of culture growth (15 days). Viability was determined by Evans blue assay. No toxic effects were observed at concentrations as high as 2 mM Mn2+. The the time dynamics of Mn accumulation in the biomass was determined using ICP. It was shown that the maximum accumulation of Mn in strain 137 (3.79 ± 0.68 μg/mg) was reached at 24h, while for PM01 the highest uptake (3.23 ± 0.17 μg/mg) was observed at 72 h. Next we analyzed redox settings by measuring the levels of reduced thiols unsing in vivo EPR spin probing. The treatment with 2 mM Mn2+ induced a rapid and irreversible decrease in the level of thiols which indicates that Mn2+ activated prooxidtaive processes. The maximum drop of thios levels were: from 4.80 ± 0.05 to 2.70 ± 0.05nmol/mg fresh weight after 1h for 137; and from 4.70 ± 0.05 to 3.40 ± 0.05 nmol/mg fresh weiht after 30 min for PM01. Further, the level of reactive oxygen species was evaluated using fluorescent probe DCFH-DA assay. The changes were in agreement with thiol levels. Both tested algal strains show resistance to Mn and are therefore good candidates for application in water bioremediation.
PB  - Faculty of Chemistry, Serbian Biochemical Society
C3  - Serbian Biochemical Society Twelfth Conference, “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia
T1  - The accumulation of manganese by Chlamydomonas acidophila strains isolated from acid mine drainage
EP  - 115
SP  - 115
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2416
ER  - 

@conference{
author = "Santrač, Isidora and Dimitrijević, Milena and Stanić, Marina and Tanović, Marija and Ćurić, Valentina and Kovačević, Snežana and Spasojević, Ivan",
year = "2023",
abstract = "Acid mine drainage ponds represents a specific artificial ecosystem that gives advantage to extemophilic microalgae. The mechanisms of adaptaton of such strains to excess metal concentrations that are common for their habitat, are poorly understood. Herein, we analzyed two strains of the green microalga Chlamydomonas acidophila - 137 and PM01, which have been isolated from different mining sites, for their interactions with Mn ions. The effects of different concentrations of Mn2+ were investigated in the late exponential/early stationary phase of culture growth (15 days). Viability was determined by Evans blue assay. No toxic effects were observed at concentrations as high as 2 mM Mn2+. The the time dynamics of Mn accumulation in the biomass was determined using ICP. It was shown that the maximum accumulation of Mn in strain 137 (3.79 ± 0.68 μg/mg) was reached at 24h, while for PM01 the highest uptake (3.23 ± 0.17 μg/mg) was observed at 72 h. Next we analyzed redox settings by measuring the levels of reduced thiols unsing in vivo EPR spin probing. The treatment with 2 mM Mn2+ induced a rapid and irreversible decrease in the level of thiols which indicates that Mn2+ activated prooxidtaive processes. The maximum drop of thios levels were: from 4.80 ± 0.05 to 2.70 ± 0.05nmol/mg fresh weight after 1h for 137; and from 4.70 ± 0.05 to 3.40 ± 0.05 nmol/mg fresh weiht after 30 min for PM01. Further, the level of reactive oxygen species was evaluated using fluorescent probe DCFH-DA assay. The changes were in agreement with thiol levels. Both tested algal strains show resistance to Mn and are therefore good candidates for application in water bioremediation.",
publisher = "Faculty of Chemistry, Serbian Biochemical Society",
journal = "Serbian Biochemical Society Twelfth Conference, “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia",
title = "The accumulation of manganese by Chlamydomonas acidophila strains isolated from acid mine drainage",
pages = "115-115",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2416"
}

Santrač, I., Dimitrijević, M., Stanić, M., Tanović, M., Ćurić, V., Kovačević, S.,& Spasojević, I.. (2023). The accumulation of manganese by Chlamydomonas acidophila strains isolated from acid mine drainage. in Serbian Biochemical Society Twelfth Conference, “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia
Faculty of Chemistry, Serbian Biochemical Society., 115-115.
https://hdl.handle.net/21.15107/rcub_rimsi_2416

Santrač I, Dimitrijević M, Stanić M, Tanović M, Ćurić V, Kovačević S, Spasojević I. The accumulation of manganese by Chlamydomonas acidophila strains isolated from acid mine drainage. in Serbian Biochemical Society Twelfth Conference, “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia. 2023;:115-115.
https://hdl.handle.net/21.15107/rcub_rimsi_2416 .

Santrač, Isidora, Dimitrijević, Milena, Stanić, Marina, Tanović, Marija, Ćurić, Valentina, Kovačević, Snežana, Spasojević, Ivan, "The accumulation of manganese by Chlamydomonas acidophila strains isolated from acid mine drainage" in Serbian Biochemical Society Twelfth Conference, “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia (2023):115-115,
https://hdl.handle.net/21.15107/rcub_rimsi_2416 .

TY  - CONF
AU  - Tanović, Marija
AU  - Dimitrijević, Milena
AU  - Milenković, Milica
AU  - Stanić, Marina
AU  - Jagličić, Zvonko
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2699
AB  - Metabolism of metals in microalgae, as well as their adaptation to metal excess, are of significant environmental importance. We have found previously that the green microalga Chlorella sorokiniana accumulates environmental Mn excess in the form of a multivalent Mn-O-Ca cluster with structure that is very similar of oxygen-evolving complex (OEC) in photosystem II1. The application of microalgae in the ‘green’ synthesis of catalytic metal clusters is very important, since the use of toxic chemicals for traditional synthesis could be avoided. The aim of this study was to investigate the magnetic, redox and structural properties of this cluster. The magnetic properties of the cluster, were tested using Low-T-EPR spectroscopy and SQUID magnetometry. Based on the analysis of the EPR spectra, it was concluded that the spin of Mn in the cluster is >1/2. In addition, the spin of Mn is not an integer since parallel mode EPR did not deliver any detectable spectrum. The paramagnetic nature of the Mn-O-Ca cluster was confirmed by the SQUID instrument. Effective magnetic moment calculated per ion Mn was ~5 BM (Mn ratio in biomass was 12,1%). For the investigation of redox and structural properties, an extract of cluster from microalga was used. Cluster extraction involved the application of a series of solvents - phenol in Tris-Cl buffer, chloroform, methanol, 0,17% sodium hypochlorite2. Cyclic and differential voltagrams were recorded in the range from -1,5 to 2 mV3. The analysis revealed the presence of different oxidation states of Mn (+2, +3, +4). The peak potentials resembled the potentials in OEC model compounds2.The redox similarities between the Mn-O-Ca cluster in microalgae and OEC imply that cluster may be have a similar catalytic activity. More detailed analysis of activity and structure of Mn-O-Ca cluster is warranted.
PB  - Serbian Biochemical Society
C3  - Serbian Biochemical Society Twelfth Conference “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia
T1  - Magnetic, redox and structural properties of Mn-O-Ca cluster, synthesized by the green microalga Chlorella sorokiniana
EP  - 125
SP  - 125
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2699
ER  - 

@conference{
author = "Tanović, Marija and Dimitrijević, Milena and Milenković, Milica and Stanić, Marina and Jagličić, Zvonko and Spasojević, Ivan",
year = "2023",
abstract = "Metabolism of metals in microalgae, as well as their adaptation to metal excess, are of significant environmental importance. We have found previously that the green microalga Chlorella sorokiniana accumulates environmental Mn excess in the form of a multivalent Mn-O-Ca cluster with structure that is very similar of oxygen-evolving complex (OEC) in photosystem II1. The application of microalgae in the ‘green’ synthesis of catalytic metal clusters is very important, since the use of toxic chemicals for traditional synthesis could be avoided. The aim of this study was to investigate the magnetic, redox and structural properties of this cluster. The magnetic properties of the cluster, were tested using Low-T-EPR spectroscopy and SQUID magnetometry. Based on the analysis of the EPR spectra, it was concluded that the spin of Mn in the cluster is >1/2. In addition, the spin of Mn is not an integer since parallel mode EPR did not deliver any detectable spectrum. The paramagnetic nature of the Mn-O-Ca cluster was confirmed by the SQUID instrument. Effective magnetic moment calculated per ion Mn was ~5 BM (Mn ratio in biomass was 12,1%). For the investigation of redox and structural properties, an extract of cluster from microalga was used. Cluster extraction involved the application of a series of solvents - phenol in Tris-Cl buffer, chloroform, methanol, 0,17% sodium hypochlorite2. Cyclic and differential voltagrams were recorded in the range from -1,5 to 2 mV3. The analysis revealed the presence of different oxidation states of Mn (+2, +3, +4). The peak potentials resembled the potentials in OEC model compounds2.The redox similarities between the Mn-O-Ca cluster in microalgae and OEC imply that cluster may be have a similar catalytic activity. More detailed analysis of activity and structure of Mn-O-Ca cluster is warranted.",
publisher = "Serbian Biochemical Society",
journal = "Serbian Biochemical Society Twelfth Conference “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia",
title = "Magnetic, redox and structural properties of Mn-O-Ca cluster, synthesized by the green microalga Chlorella sorokiniana",
pages = "125-125",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2699"
}

Tanović, M., Dimitrijević, M., Milenković, M., Stanić, M., Jagličić, Z.,& Spasojević, I.. (2023). Magnetic, redox and structural properties of Mn-O-Ca cluster, synthesized by the green microalga Chlorella sorokiniana. in Serbian Biochemical Society Twelfth Conference “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia
Serbian Biochemical Society., 125-125.
https://hdl.handle.net/21.15107/rcub_rimsi_2699

Tanović M, Dimitrijević M, Milenković M, Stanić M, Jagličić Z, Spasojević I. Magnetic, redox and structural properties of Mn-O-Ca cluster, synthesized by the green microalga Chlorella sorokiniana. in Serbian Biochemical Society Twelfth Conference “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia. 2023;:125-125.
https://hdl.handle.net/21.15107/rcub_rimsi_2699 .

Tanović, Marija, Dimitrijević, Milena, Milenković, Milica, Stanić, Marina, Jagličić, Zvonko, Spasojević, Ivan, "Magnetic, redox and structural properties of Mn-O-Ca cluster, synthesized by the green microalga Chlorella sorokiniana" in Serbian Biochemical Society Twelfth Conference “Biochemistry in Biotechnology”, September 21-23, 2023, Belgrade, Serbia (2023):125-125,
https://hdl.handle.net/21.15107/rcub_rimsi_2699 .

TY  - GEN
AU  - Stojiljković, Danica
AU  - Spasojević, Ivan
PY  - 2023
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2413
AB  - Limited space, high commercial value of the
land, and air and soil pollution that is detrimental to
plants prevent traditional greening using trees and
lawns in urban environments with high population
density and intensive traffic. Urban photo-bioreactor
LIQUID3 represents an alternative concept of
greening that was developed for such urban
environments. LIQUID3 exploits high efficiency of
microalgae in CO2 fixation and O2 and biomass
production, as well as water column filtration that
removes PM particles from the polluted air. A
multidisciplinary approach was applied to integrate
biotechnological application with urban functions
– bench, USB solar charger, and nightlight, and
contemporary design, which represent the basis
of its functionality and viability in the urban space.
Alternative concepts of greening like LIQUID3 enable
smart use of city space, promote environmental
awareness, and support even distribution of greenery
throughout the city, which is related to economic
prosperity, social justice and sustainability. The
innovative idea of urban photo-bioreactor LIQUID3
has been developed from the concept to the
prototype at the University of Belgrade – Institute
for Multidisciplinary Research with the support of
UNDP Serbia, Global Environmental Facility and the
Ministry of Environmental Protection of the Republic
of Serbia. The prototype was installed in the centre
of Belgrade in September 2021
PB  - University of Belgrade - Faculty of Architecture
T2  - Conference Eco-friendly Built Environment
T1  - AN ALTERNATIVE CONCEPT OF URBAN GREENING: URBAN PHOTOBIOREACTOR LIQUID3
SP  - 21
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2413
ER  - 

@misc{
author = "Stojiljković, Danica and Spasojević, Ivan",
year = "2023",
abstract = "Limited space, high commercial value of the
land, and air and soil pollution that is detrimental to
plants prevent traditional greening using trees and
lawns in urban environments with high population
density and intensive traffic. Urban photo-bioreactor
LIQUID3 represents an alternative concept of
greening that was developed for such urban
environments. LIQUID3 exploits high efficiency of
microalgae in CO2 fixation and O2 and biomass
production, as well as water column filtration that
removes PM particles from the polluted air. A
multidisciplinary approach was applied to integrate
biotechnological application with urban functions
– bench, USB solar charger, and nightlight, and
contemporary design, which represent the basis
of its functionality and viability in the urban space.
Alternative concepts of greening like LIQUID3 enable
smart use of city space, promote environmental
awareness, and support even distribution of greenery
throughout the city, which is related to economic
prosperity, social justice and sustainability. The
innovative idea of urban photo-bioreactor LIQUID3
has been developed from the concept to the
prototype at the University of Belgrade – Institute
for Multidisciplinary Research with the support of
UNDP Serbia, Global Environmental Facility and the
Ministry of Environmental Protection of the Republic
of Serbia. The prototype was installed in the centre
of Belgrade in September 2021",
publisher = "University of Belgrade - Faculty of Architecture",
journal = "Conference Eco-friendly Built Environment",
title = "AN ALTERNATIVE CONCEPT OF URBAN GREENING: URBAN PHOTOBIOREACTOR LIQUID3",
pages = "21",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2413"
}

Stojiljković, D.,& Spasojević, I.. (2023). AN ALTERNATIVE CONCEPT OF URBAN GREENING: URBAN PHOTOBIOREACTOR LIQUID3. in Conference Eco-friendly Built Environment
University of Belgrade - Faculty of Architecture., 21.
https://hdl.handle.net/21.15107/rcub_rimsi_2413

Stojiljković D, Spasojević I. AN ALTERNATIVE CONCEPT OF URBAN GREENING: URBAN PHOTOBIOREACTOR LIQUID3. in Conference Eco-friendly Built Environment. 2023;:21.
https://hdl.handle.net/21.15107/rcub_rimsi_2413 .

Stojiljković, Danica, Spasojević, Ivan, "AN ALTERNATIVE CONCEPT OF URBAN GREENING: URBAN PHOTOBIOREACTOR LIQUID3" in Conference Eco-friendly Built Environment (2023):21,
https://hdl.handle.net/21.15107/rcub_rimsi_2413 .

TY  - CONF
AU  - Ćukić, Aleksandra
AU  - Dimitrijević, Milena
AU  - Kovačević, Snežana
AU  - Opačić, Miloš
AU  - Stanić, Marina
AU  - Žižić, Milan
AU  - Spasojević, Ivan
PY  - 2022
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2419
AB  - Индустријализацијом и употребом фосилних горива, водени екосистеми су све више загађени тешким металима, укључујући и никл. Једноћелијске алге представљају значајне карике у процесу биоремедијације отпадних вода. Као стресор, никл доводи до стварања реактивних врста кисеоника (ROS) код зелених алги. Механизми за заштиту од ROS обухватају неензимске и ензимске антиоксидансе као што су глутатион, аскорбат, каротеноиди, супероксид дисмутазe (CuZnSOD, FeSOD и MnSOD), каталаза (CAT), глутатион пероксидаза и глутатион редуктаза. Циљ овог рада је био да се испитају нивои антиоксидативних ензима једноћелијске алге C. sorokiniana гајене у култури и излагане високој али нетоксичној концентрацији јона Ni(II) (1 mM) у трајању од 1 h и 24 h. Методом Western blot детектовани су нивои FeSOD, MnSOD и CAT у ћелијским екстрактима контролних и никлом третираних узорака микроалги. Тренд смањења нивоа FeSOD и MnSOD протеина уочен је након једносатног третмана никлом. Код третмана од 24 h ниво FeSOD остаје смањен, док се ниво MnSOD враћа на контролне вредности. Није било промена у нивоу CAT. Показано је да акутни стрес изазван 1 mM Ni(II), који укључује повећан ниво ROS (што је установљено одговарајућим есејима), не доводи до статистички значајних промена у нивоу испитиваних антиоксидативних ензима код C. sorokiniana. Потребно је испитати остале компоненте антиоксидативне заштите које вероватно учествују у уклањању ROS индукованих на овај начин.
PB  - Srpsko biološko društvo, Beograd, 2022
C3  - Treći kongres biologa Srbije, osnovna i primenjena istraživanja, metodika nastave. Zlatibor, Srbija 21 – 25. 9. 2022.
T1  - Uticaj povećane koncentracije jona Ni(II) na nivo antioksidativnih enzima u jednoćelijskoj algi Chlorella sorokiniana
EP  - 230
SP  - 230
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2419
ER  - 

@conference{
author = "Ćukić, Aleksandra and Dimitrijević, Milena and Kovačević, Snežana and Opačić, Miloš and Stanić, Marina and Žižić, Milan and Spasojević, Ivan",
year = "2022",
abstract = "Индустријализацијом и употребом фосилних горива, водени екосистеми су све више загађени тешким металима, укључујући и никл. Једноћелијске алге представљају значајне карике у процесу биоремедијације отпадних вода. Као стресор, никл доводи до стварања реактивних врста кисеоника (ROS) код зелених алги. Механизми за заштиту од ROS обухватају неензимске и ензимске антиоксидансе као што су глутатион, аскорбат, каротеноиди, супероксид дисмутазe (CuZnSOD, FeSOD и MnSOD), каталаза (CAT), глутатион пероксидаза и глутатион редуктаза. Циљ овог рада је био да се испитају нивои антиоксидативних ензима једноћелијске алге C. sorokiniana гајене у култури и излагане високој али нетоксичној концентрацији јона Ni(II) (1 mM) у трајању од 1 h и 24 h. Методом Western blot детектовани су нивои FeSOD, MnSOD и CAT у ћелијским екстрактима контролних и никлом третираних узорака микроалги. Тренд смањења нивоа FeSOD и MnSOD протеина уочен је након једносатног третмана никлом. Код третмана од 24 h ниво FeSOD остаје смањен, док се ниво MnSOD враћа на контролне вредности. Није било промена у нивоу CAT. Показано је да акутни стрес изазван 1 mM Ni(II), који укључује повећан ниво ROS (што је установљено одговарајућим есејима), не доводи до статистички значајних промена у нивоу испитиваних антиоксидативних ензима код C. sorokiniana. Потребно је испитати остале компоненте антиоксидативне заштите које вероватно учествују у уклањању ROS индукованих на овај начин.",
publisher = "Srpsko biološko društvo, Beograd, 2022",
journal = "Treći kongres biologa Srbije, osnovna i primenjena istraživanja, metodika nastave. Zlatibor, Srbija 21 – 25. 9. 2022.",
title = "Uticaj povećane koncentracije jona Ni(II) na nivo antioksidativnih enzima u jednoćelijskoj algi Chlorella sorokiniana",
pages = "230-230",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2419"
}

Ćukić, A., Dimitrijević, M., Kovačević, S., Opačić, M., Stanić, M., Žižić, M.,& Spasojević, I.. (2022). Uticaj povećane koncentracije jona Ni(II) na nivo antioksidativnih enzima u jednoćelijskoj algi Chlorella sorokiniana. in Treći kongres biologa Srbije, osnovna i primenjena istraživanja, metodika nastave. Zlatibor, Srbija 21 – 25. 9. 2022.
Srpsko biološko društvo, Beograd, 2022., 230-230.
https://hdl.handle.net/21.15107/rcub_rimsi_2419

Ćukić A, Dimitrijević M, Kovačević S, Opačić M, Stanić M, Žižić M, Spasojević I. Uticaj povećane koncentracije jona Ni(II) na nivo antioksidativnih enzima u jednoćelijskoj algi Chlorella sorokiniana. in Treći kongres biologa Srbije, osnovna i primenjena istraživanja, metodika nastave. Zlatibor, Srbija 21 – 25. 9. 2022.. 2022;:230-230.
https://hdl.handle.net/21.15107/rcub_rimsi_2419 .

Ćukić, Aleksandra, Dimitrijević, Milena, Kovačević, Snežana, Opačić, Miloš, Stanić, Marina, Žižić, Milan, Spasojević, Ivan, "Uticaj povećane koncentracije jona Ni(II) na nivo antioksidativnih enzima u jednoćelijskoj algi Chlorella sorokiniana" in Treći kongres biologa Srbije, osnovna i primenjena istraživanja, metodika nastave. Zlatibor, Srbija 21 – 25. 9. 2022. (2022):230-230,
https://hdl.handle.net/21.15107/rcub_rimsi_2419 .

TY  - CONF
AU  - Vojvodić, Snežana
AU  - Stanić, Marina
AU  - Danilović Luković, Jelena
AU  - Milivojević, Marija
AU  - Zechmann, Bernd
AU  - Dimitrijević, Milena
AU  - Opačić, Miloš
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2022
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2403
AB  - METHODS
The impact of a set of concentrations of Mn2+ and Ni2+ on growth of C. sorokiniana culture in 3N-BBM+V
medium in the early stationary phase was evaluated by changes in optical density at 750 nm and biomass
during 7 days treatment. Mucilage release was analyzed using SEM microscopy. Redox settings were analyzed
by oxidation-sensitive fluorescent probe and assays for thiols.
RESULTS
Ni was more toxic than Mn and affected culture growth at lower concentrations. Microalgal cells started
releasing mucilage polymers within 1 h of exposure to 1 mM Mn2+, whereas no mucilage was observed even
at 24 h of treatment with equimolar Ni2+. The peak of reactive oxygen species production was reached faster
for Ni2+ than Mn2+. Mn-induced drops in the concentration of reduced thiols showed a recovery after 1 h and
24 h. Ni2+-induced drop was irreversible. The observed differences between the impact of Mn and Ni may be
related to different redox and coordinative properties and to higher capacities of microalgae to sequester Mn
in relation to higher quotas than Ni that are required for normal functio
C3  - FEMS Conference on Microbiology (in association with Serbian Society of Microbiology), Belgrade, Serbia.
T1  - Comparative impact of Mn2+ and Ni2+ on the microalga Chlorella sorokiniana
EP  - 748
SP  - 747
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2403
ER  - 

@conference{
author = "Vojvodić, Snežana and Stanić, Marina and Danilović Luković, Jelena and Milivojević, Marija and Zechmann, Bernd and Dimitrijević, Milena and Opačić, Miloš and Pittman, Jon K. and Spasojević, Ivan",
year = "2022",
abstract = "METHODS
The impact of a set of concentrations of Mn2+ and Ni2+ on growth of C. sorokiniana culture in 3N-BBM+V
medium in the early stationary phase was evaluated by changes in optical density at 750 nm and biomass
during 7 days treatment. Mucilage release was analyzed using SEM microscopy. Redox settings were analyzed
by oxidation-sensitive fluorescent probe and assays for thiols.
RESULTS
Ni was more toxic than Mn and affected culture growth at lower concentrations. Microalgal cells started
releasing mucilage polymers within 1 h of exposure to 1 mM Mn2+, whereas no mucilage was observed even
at 24 h of treatment with equimolar Ni2+. The peak of reactive oxygen species production was reached faster
for Ni2+ than Mn2+. Mn-induced drops in the concentration of reduced thiols showed a recovery after 1 h and
24 h. Ni2+-induced drop was irreversible. The observed differences between the impact of Mn and Ni may be
related to different redox and coordinative properties and to higher capacities of microalgae to sequester Mn
in relation to higher quotas than Ni that are required for normal functio",
journal = "FEMS Conference on Microbiology (in association with Serbian Society of Microbiology), Belgrade, Serbia.",
title = "Comparative impact of Mn2+ and Ni2+ on the microalga Chlorella sorokiniana",
pages = "748-747",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2403"
}

Vojvodić, S., Stanić, M., Danilović Luković, J., Milivojević, M., Zechmann, B., Dimitrijević, M., Opačić, M., Pittman, J. K.,& Spasojević, I.. (2022). Comparative impact of Mn2+ and Ni2+ on the microalga Chlorella sorokiniana. in FEMS Conference on Microbiology (in association with Serbian Society of Microbiology), Belgrade, Serbia., 747-748.
https://hdl.handle.net/21.15107/rcub_rimsi_2403

Vojvodić S, Stanić M, Danilović Luković J, Milivojević M, Zechmann B, Dimitrijević M, Opačić M, Pittman JK, Spasojević I. Comparative impact of Mn2+ and Ni2+ on the microalga Chlorella sorokiniana. in FEMS Conference on Microbiology (in association with Serbian Society of Microbiology), Belgrade, Serbia.. 2022;:747-748.
https://hdl.handle.net/21.15107/rcub_rimsi_2403 .

Vojvodić, Snežana, Stanić, Marina, Danilović Luković, Jelena, Milivojević, Marija, Zechmann, Bernd, Dimitrijević, Milena, Opačić, Miloš, Pittman, Jon K., Spasojević, Ivan, "Comparative impact of Mn2+ and Ni2+ on the microalga Chlorella sorokiniana" in FEMS Conference on Microbiology (in association with Serbian Society of Microbiology), Belgrade, Serbia. (2022):747-748,
https://hdl.handle.net/21.15107/rcub_rimsi_2403 .

TY  - CONF
AU  - Vojvodić, Snežana
AU  - Opačić, Miloš
AU  - Stanić, Marina
AU  - Dimitrijević, Milena
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2022
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2417
AB  - Nickel is utilized by microalgae as a co-factor of urease. On the other hand, this transition metal represents an important pollutant of aquatic ecosystems. The effects of Ni(II) excess on microalgae and the mechanisms of adaptation are poorly understood. Redox processes represent an important component of the mechanisms of interaction of microalgae with transition metals. Pertinent to this, we analyzed redox changes in Chlorella sorokiniana culture that are induced by high levels of Ni(II). The intracellular level of reactive oxygen species (ROS) showed a rapid two-phase increase that took place prior to Ni accumulation in the cell. This was accompanied by oxidation of thiols and drastic deglutathyonilation of proteins. PAM fluorimetry showed that Ni excess induced an increase in the efficiency of photosystem II and promoted electron flow in chloroplasts, which is most likely responsible for ROS rise. In addition, a rising trend in the chlorophyll level was observed. On the other hand, the level of lipid peroxidation and activities of key antioxidative enzymes were not increased, which implies that oxidative stress is not an important player in Ni adaptation/toxicity. After prolonged exposure the efficiency of photosystem II drops, nickel is accumulated in the cells, and new redox balance is established. Our results imply that redox signalling is involved in Ni-induced metabolic activation and that key changes take place in photosynthetic machinery.
PB  - Faculty of Chemistry, Serbian Biochemical Society
C3  - Serbian Biochemical Society Eleventh Conference, “Amazing Biochemistry”. September 22nd and 23rd, 2022, Novi Sad, Serbia
T1  - Redox component in the adaptation of the microalga Chlorella sorokiniana to Ni(II) excess
EP  - 133
SP  - 133
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2417
ER  - 

@conference{
author = "Vojvodić, Snežana and Opačić, Miloš and Stanić, Marina and Dimitrijević, Milena and Pittman, Jon K. and Spasojević, Ivan",
year = "2022",
abstract = "Nickel is utilized by microalgae as a co-factor of urease. On the other hand, this transition metal represents an important pollutant of aquatic ecosystems. The effects of Ni(II) excess on microalgae and the mechanisms of adaptation are poorly understood. Redox processes represent an important component of the mechanisms of interaction of microalgae with transition metals. Pertinent to this, we analyzed redox changes in Chlorella sorokiniana culture that are induced by high levels of Ni(II). The intracellular level of reactive oxygen species (ROS) showed a rapid two-phase increase that took place prior to Ni accumulation in the cell. This was accompanied by oxidation of thiols and drastic deglutathyonilation of proteins. PAM fluorimetry showed that Ni excess induced an increase in the efficiency of photosystem II and promoted electron flow in chloroplasts, which is most likely responsible for ROS rise. In addition, a rising trend in the chlorophyll level was observed. On the other hand, the level of lipid peroxidation and activities of key antioxidative enzymes were not increased, which implies that oxidative stress is not an important player in Ni adaptation/toxicity. After prolonged exposure the efficiency of photosystem II drops, nickel is accumulated in the cells, and new redox balance is established. Our results imply that redox signalling is involved in Ni-induced metabolic activation and that key changes take place in photosynthetic machinery.",
publisher = "Faculty of Chemistry, Serbian Biochemical Society",
journal = "Serbian Biochemical Society Eleventh Conference, “Amazing Biochemistry”. September 22nd and 23rd, 2022, Novi Sad, Serbia",
title = "Redox component in the adaptation of the microalga Chlorella sorokiniana to Ni(II) excess",
pages = "133-133",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2417"
}

Vojvodić, S., Opačić, M., Stanić, M., Dimitrijević, M., Pittman, J. K.,& Spasojević, I.. (2022). Redox component in the adaptation of the microalga Chlorella sorokiniana to Ni(II) excess. in Serbian Biochemical Society Eleventh Conference, “Amazing Biochemistry”. September 22nd and 23rd, 2022, Novi Sad, Serbia
Faculty of Chemistry, Serbian Biochemical Society., 133-133.
https://hdl.handle.net/21.15107/rcub_rimsi_2417

Vojvodić S, Opačić M, Stanić M, Dimitrijević M, Pittman JK, Spasojević I. Redox component in the adaptation of the microalga Chlorella sorokiniana to Ni(II) excess. in Serbian Biochemical Society Eleventh Conference, “Amazing Biochemistry”. September 22nd and 23rd, 2022, Novi Sad, Serbia. 2022;:133-133.
https://hdl.handle.net/21.15107/rcub_rimsi_2417 .

Vojvodić, Snežana, Opačić, Miloš, Stanić, Marina, Dimitrijević, Milena, Pittman, Jon K., Spasojević, Ivan, "Redox component in the adaptation of the microalga Chlorella sorokiniana to Ni(II) excess" in Serbian Biochemical Society Eleventh Conference, “Amazing Biochemistry”. September 22nd and 23rd, 2022, Novi Sad, Serbia (2022):133-133,
https://hdl.handle.net/21.15107/rcub_rimsi_2417 .

TY  - JOUR
AU  - Baralic, Marko
AU  - Spasojević, Ivan
AU  - Miljus, Goran
AU  - Šunderić, Miloš
AU  - Robajac, Dragana
AU  - Dobrijević, Zorana
AU  - Gligorijević, Nikola
AU  - Nedic, Olgica
AU  - Penezic, Ana
PY  - 2022
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2985
AB  - Albumin (HSA) is a multifunctional protein and due to its free Cys34 thiol group, represents a main source of free
thiols in the circulation. This property of HSA, combined with its ability to sequester redox active Cu(II) ions,
makes HSA a dominant circulatory antioxidant. End stage kidney disease (ESRD) is a condition accompanied by
elevated oxidative stress. The aim of the present study was to examine changes in the antioxidative capacity of
HSA and Cu(II) binding affinity in patients on peritoneal dialysis (PD), and relate it to the Cys34 thiol group
content and other structural changes of this molecule.
HSA molecules are modified in ESRD patients subjected to PD, having significantly lower thiol group and
bound Cu(II) content, reduced antioxidant capacity, an increased content of advanced glycation end-products
and altered conformation. Also, Cu(II) binding capacity of HSA in these patients is impaired, since a significant
portion of the high-affinity metal-binding site is unable to interact with Cu(II).
Taking into account that the concentration of Cu(II) in the circulation of ESRD patients is much higher than in
healthy persons and that Cu(II) binding capacity of HSA in these patients is significantly impaired, HSA may be
considered as a novel circulatory pro-oxidant, thus exacerbating oxidative stress.
PB  - Elsevier
T2  - Free radical biology and medicine
T1  - Albumin at the intersection between antioxidant and pro-oxidant in patients on peritoneal dialysis
EP  - 112
SP  - 105
VL  - 187
DO  - 10.1016/j.freeradbiomed.2022.05.019
ER  - 

@article{
author = "Baralic, Marko and Spasojević, Ivan and Miljus, Goran and Šunderić, Miloš and Robajac, Dragana and Dobrijević, Zorana and Gligorijević, Nikola and Nedic, Olgica and Penezic, Ana",
year = "2022",
abstract = "Albumin (HSA) is a multifunctional protein and due to its free Cys34 thiol group, represents a main source of free
thiols in the circulation. This property of HSA, combined with its ability to sequester redox active Cu(II) ions,
makes HSA a dominant circulatory antioxidant. End stage kidney disease (ESRD) is a condition accompanied by
elevated oxidative stress. The aim of the present study was to examine changes in the antioxidative capacity of
HSA and Cu(II) binding affinity in patients on peritoneal dialysis (PD), and relate it to the Cys34 thiol group
content and other structural changes of this molecule.
HSA molecules are modified in ESRD patients subjected to PD, having significantly lower thiol group and
bound Cu(II) content, reduced antioxidant capacity, an increased content of advanced glycation end-products
and altered conformation. Also, Cu(II) binding capacity of HSA in these patients is impaired, since a significant
portion of the high-affinity metal-binding site is unable to interact with Cu(II).
Taking into account that the concentration of Cu(II) in the circulation of ESRD patients is much higher than in
healthy persons and that Cu(II) binding capacity of HSA in these patients is significantly impaired, HSA may be
considered as a novel circulatory pro-oxidant, thus exacerbating oxidative stress.",
publisher = "Elsevier",
journal = "Free radical biology and medicine",
title = "Albumin at the intersection between antioxidant and pro-oxidant in patients on peritoneal dialysis",
pages = "112-105",
volume = "187",
doi = "10.1016/j.freeradbiomed.2022.05.019"
}

Baralic, M., Spasojević, I., Miljus, G., Šunderić, M., Robajac, D., Dobrijević, Z., Gligorijević, N., Nedic, O.,& Penezic, A.. (2022). Albumin at the intersection between antioxidant and pro-oxidant in patients on peritoneal dialysis. in Free radical biology and medicine
Elsevier., 187, 105-112.
https://doi.org/10.1016/j.freeradbiomed.2022.05.019

Baralic M, Spasojević I, Miljus G, Šunderić M, Robajac D, Dobrijević Z, Gligorijević N, Nedic O, Penezic A. Albumin at the intersection between antioxidant and pro-oxidant in patients on peritoneal dialysis. in Free radical biology and medicine. 2022;187:105-112.
doi:10.1016/j.freeradbiomed.2022.05.019 .

Baralic, Marko, Spasojević, Ivan, Miljus, Goran, Šunderić, Miloš, Robajac, Dragana, Dobrijević, Zorana, Gligorijević, Nikola, Nedic, Olgica, Penezic, Ana, "Albumin at the intersection between antioxidant and pro-oxidant in patients on peritoneal dialysis" in Free radical biology and medicine, 187 (2022):105-112,
https://doi.org/10.1016/j.freeradbiomed.2022.05.019 . .

TY  - CONF
AU  - Penezic, Ana
AU  - Baralic, Marko
AU  - Spasojević, Ivan
AU  - Šunderić, Miloš
AU  - Miljus, Goran
AU  - Robajac, Dragana
AU  - Dobrijević, Zorana
AU  - Nedic, Olgica
AU  - Gligorijević, Nikola
PY  - 2022
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2865
AB  - Albumin (HSA) is a multifunctional serum protein. Free Cys34 thiol group makes HSA a major source of free thiols in the circulation. HSA is also a dominant carrier of exchangeable copper pool with a high affinity binding site for this redox-active ion, located at the N-terminus. Combination of these two properties highlights HSA as a powerful circulatory antioxidant. The presence of free thiol groups in HSA and its copper binding capacity have been shown to be interconnected and essential for the binding and sequestering of copper ions, thus preventing metal-catalysed production of reactive oxygen species. End stage kidney disease (ESRD) is a condition accompanied by oxidative stress. The aim of this study was to examine changes in the antioxidative capacity of HSA and Cu(II) binding affinity in patients on peritoneal dialysis (PD), and relate it to the Cys34 thiol group content and structural changes of this molecule. HSA molecules are modified in ESRD patients on PD, having lower content of bound copper ions and thiol groups, reduced copper binding affinity and overall antioxidant capacity. An increased content of advanced glycation end-products and altered conformation was detected in HSA from PD patients. Function of HSA as a sequestrator of free Cu(II) ions, is impaired. A significant portion of the high-affinity metal-binding site was unable to interact with Cu(II) ions, as shown by EPR. Similar results on copper binding were obtained in subgroups of patients with and without diabetes mellitus, suggesting that ESRD and constant exposure to high glucose concentration during dialysis influenced protein modification. Since the concentration of Cu(II) in the circulation of these patients is much higher than in healthy persons and that Cu(II) binding capacity of albumin from patients is significantly lower, the albumin may be considered to turn from antioxidant to pro-oxidant activity.
PB  - Biohemijsko drustvo Srbije
C3  - "Amazing Biochemistry" : [proceedings] / Serbian Biochemical Society, Eleventh Conference, Scientific meeting of an international character, September 22nd and 23rd, 2022, Novi Sad, Serbia
T1  - Albumin: antioxidant or pro-oxidant in patients on peritoneal dialysis?
SP  - 118
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2865
ER  - 

@conference{
author = "Penezic, Ana and Baralic, Marko and Spasojević, Ivan and Šunderić, Miloš and Miljus, Goran and Robajac, Dragana and Dobrijević, Zorana and Nedic, Olgica and Gligorijević, Nikola",
year = "2022",
abstract = "Albumin (HSA) is a multifunctional serum protein. Free Cys34 thiol group makes HSA a major source of free thiols in the circulation. HSA is also a dominant carrier of exchangeable copper pool with a high affinity binding site for this redox-active ion, located at the N-terminus. Combination of these two properties highlights HSA as a powerful circulatory antioxidant. The presence of free thiol groups in HSA and its copper binding capacity have been shown to be interconnected and essential for the binding and sequestering of copper ions, thus preventing metal-catalysed production of reactive oxygen species. End stage kidney disease (ESRD) is a condition accompanied by oxidative stress. The aim of this study was to examine changes in the antioxidative capacity of HSA and Cu(II) binding affinity in patients on peritoneal dialysis (PD), and relate it to the Cys34 thiol group content and structural changes of this molecule. HSA molecules are modified in ESRD patients on PD, having lower content of bound copper ions and thiol groups, reduced copper binding affinity and overall antioxidant capacity. An increased content of advanced glycation end-products and altered conformation was detected in HSA from PD patients. Function of HSA as a sequestrator of free Cu(II) ions, is impaired. A significant portion of the high-affinity metal-binding site was unable to interact with Cu(II) ions, as shown by EPR. Similar results on copper binding were obtained in subgroups of patients with and without diabetes mellitus, suggesting that ESRD and constant exposure to high glucose concentration during dialysis influenced protein modification. Since the concentration of Cu(II) in the circulation of these patients is much higher than in healthy persons and that Cu(II) binding capacity of albumin from patients is significantly lower, the albumin may be considered to turn from antioxidant to pro-oxidant activity.",
publisher = "Biohemijsko drustvo Srbije",
journal = ""Amazing Biochemistry" : [proceedings] / Serbian Biochemical Society, Eleventh Conference, Scientific meeting of an international character, September 22nd and 23rd, 2022, Novi Sad, Serbia",
title = "Albumin: antioxidant or pro-oxidant in patients on peritoneal dialysis?",
pages = "118",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2865"
}

Penezic, A., Baralic, M., Spasojević, I., Šunderić, M., Miljus, G., Robajac, D., Dobrijević, Z., Nedic, O.,& Gligorijević, N.. (2022). Albumin: antioxidant or pro-oxidant in patients on peritoneal dialysis?. in "Amazing Biochemistry" : [proceedings] / Serbian Biochemical Society, Eleventh Conference, Scientific meeting of an international character, September 22nd and 23rd, 2022, Novi Sad, Serbia
Biohemijsko drustvo Srbije., 118.
https://hdl.handle.net/21.15107/rcub_rimsi_2865

Penezic A, Baralic M, Spasojević I, Šunderić M, Miljus G, Robajac D, Dobrijević Z, Nedic O, Gligorijević N. Albumin: antioxidant or pro-oxidant in patients on peritoneal dialysis?. in "Amazing Biochemistry" : [proceedings] / Serbian Biochemical Society, Eleventh Conference, Scientific meeting of an international character, September 22nd and 23rd, 2022, Novi Sad, Serbia. 2022;:118.
https://hdl.handle.net/21.15107/rcub_rimsi_2865 .

Penezic, Ana, Baralic, Marko, Spasojević, Ivan, Šunderić, Miloš, Miljus, Goran, Robajac, Dragana, Dobrijević, Zorana, Nedic, Olgica, Gligorijević, Nikola, "Albumin: antioxidant or pro-oxidant in patients on peritoneal dialysis?" in "Amazing Biochemistry" : [proceedings] / Serbian Biochemical Society, Eleventh Conference, Scientific meeting of an international character, September 22nd and 23rd, 2022, Novi Sad, Serbia (2022):118,
https://hdl.handle.net/21.15107/rcub_rimsi_2865 .

TY  - CONF
AU  - Vojvodić, Snežana
AU  - Dimitrijević, Milena
AU  - Dučić, Tanja
AU  - Stanković, Dalibor
AU  - Opačić, Miloš
AU  - Stanić, Marina
AU  - Žižić, Milan
AU  - Spasojević, Ivan
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2391
AB  - Microalgae can be implemented in the remediation of mining and other metal-rich wastewaters as pioneer species. On the other hand, metals affect aquatic ecosystems through the negative impact on microalgae which are the primary producers of O2 and biomass. Redox processes represent an important component of the mechanisms of interaction of microalgae with transition metals. We analyzed the redox changes in Chlorella sorokiniana culture that are induced by high levels of Mn(II). Mn is the key metal pollutant, with five main oxidation forms that can bind to a variety of different ligands. Mn (1 mM) induced a significant increase in the intracellular production of reactive oxygen species. The boost appears to show two phases – the first is very fast (observed after 15 min), whereas the second starts after 1 h reaching a plateau at 24 h. The concentration of reduced thiols, which represent important targets of oxidation, appears to parallel this trend. Total glutathione concentration shows a drop at 1 h and recovery at 24 h. This implicates that either a glutathionylation of proteins or a synthesis of phytochelatins - sulfur-rich short-chain peptides that sequester metals, takes place early in the response to Mn. Further, FTIR analysis showed that Mn induced a decrease of C=C levels and CH2/CH3 ratio implicating increased lipid peroxidation. Finally, Mn ions that were accumulated in the cells were extracted with nitric oxide and analyzed by cyclic voltammetry. Two redox forms were detected - Mn(II) and Mn(IV). The latter appears to prevail at higher manganese concentrations and longer periods of incubation. These results demonstrate that redox response of C. sorokiniana to high Mn levels involves at least two phases. Initially, Mn(II) enters the cells and induces pro-oxidative changes that are mitigated by glutathione-based antioxidative defense. Later on, redox homeostasis is reestablished with concomitant inactivation of Mn in the more stable redox form.
PB  - Faculty of Chemistry, Serbian Biochemical Society
C3  - Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia
T1  - Redox changes in microalga Chlorella sorokiniana exposed to high concentrations of Mn(II)
EP  - 174
SP  - 174
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2391
ER  - 

@conference{
author = "Vojvodić, Snežana and Dimitrijević, Milena and Dučić, Tanja and Stanković, Dalibor and Opačić, Miloš and Stanić, Marina and Žižić, Milan and Spasojević, Ivan",
year = "2021",
abstract = "Microalgae can be implemented in the remediation of mining and other metal-rich wastewaters as pioneer species. On the other hand, metals affect aquatic ecosystems through the negative impact on microalgae which are the primary producers of O2 and biomass. Redox processes represent an important component of the mechanisms of interaction of microalgae with transition metals. We analyzed the redox changes in Chlorella sorokiniana culture that are induced by high levels of Mn(II). Mn is the key metal pollutant, with five main oxidation forms that can bind to a variety of different ligands. Mn (1 mM) induced a significant increase in the intracellular production of reactive oxygen species. The boost appears to show two phases – the first is very fast (observed after 15 min), whereas the second starts after 1 h reaching a plateau at 24 h. The concentration of reduced thiols, which represent important targets of oxidation, appears to parallel this trend. Total glutathione concentration shows a drop at 1 h and recovery at 24 h. This implicates that either a glutathionylation of proteins or a synthesis of phytochelatins - sulfur-rich short-chain peptides that sequester metals, takes place early in the response to Mn. Further, FTIR analysis showed that Mn induced a decrease of C=C levels and CH2/CH3 ratio implicating increased lipid peroxidation. Finally, Mn ions that were accumulated in the cells were extracted with nitric oxide and analyzed by cyclic voltammetry. Two redox forms were detected - Mn(II) and Mn(IV). The latter appears to prevail at higher manganese concentrations and longer periods of incubation. These results demonstrate that redox response of C. sorokiniana to high Mn levels involves at least two phases. Initially, Mn(II) enters the cells and induces pro-oxidative changes that are mitigated by glutathione-based antioxidative defense. Later on, redox homeostasis is reestablished with concomitant inactivation of Mn in the more stable redox form.",
publisher = "Faculty of Chemistry, Serbian Biochemical Society",
journal = "Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia",
title = "Redox changes in microalga Chlorella sorokiniana exposed to high concentrations of Mn(II)",
pages = "174-174",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2391"
}

Vojvodić, S., Dimitrijević, M., Dučić, T., Stanković, D., Opačić, M., Stanić, M., Žižić, M.,& Spasojević, I.. (2021). Redox changes in microalga Chlorella sorokiniana exposed to high concentrations of Mn(II). in Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia
Faculty of Chemistry, Serbian Biochemical Society., 174-174.
https://hdl.handle.net/21.15107/rcub_rimsi_2391

Vojvodić S, Dimitrijević M, Dučić T, Stanković D, Opačić M, Stanić M, Žižić M, Spasojević I. Redox changes in microalga Chlorella sorokiniana exposed to high concentrations of Mn(II). in Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia. 2021;:174-174.
https://hdl.handle.net/21.15107/rcub_rimsi_2391 .

Vojvodić, Snežana, Dimitrijević, Milena, Dučić, Tanja, Stanković, Dalibor, Opačić, Miloš, Stanić, Marina, Žižić, Milan, Spasojević, Ivan, "Redox changes in microalga Chlorella sorokiniana exposed to high concentrations of Mn(II)" in Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia (2021):174-174,
https://hdl.handle.net/21.15107/rcub_rimsi_2391 .

TY  - CONF
AU  - Vojvodić, Snežana
AU  - Stanić, Marina
AU  - Zechmann, Bernd
AU  - Dimitrijević, Milena
AU  - Opačić, Miloš
AU  - Danilović Luković, Jelena
AU  - Morina, Arian
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2420
AB  - Many neutrophilic and acidophilic microalgal species tolerate high metal concentrations
and can survive or colonize metal-polluted waters. They show significant biotechnological
potential for the remediation and wastewaters processing. On the other hand, negative effects
of metal pollution on microalgae may affect the function of aquatic ecosystems because these
photosynthetic microorganisms represent the primary producers of O2 and biomass. However,
adaptive mechanisms that microalgae employ to detoxify metal excess are largely unknown.
Herein we analyzed the response of the freshwater microalga Chlorella sorokiniana to high
but non-toxic levels of Mn2+. Manganese is a key metal pollutant, with five possible oxidation
forms that can bind to a variety of different ligands. At pH below 7, it is predominantly present in
Mn2+ form. Scanning electron microscopy showed that in response to 1 mM Mn2+, C. sorokiniana
released mucilage polymers within 1 h. Electron paramagnetic resonance spectroscopy (EPR)
showed that the early response involved loose Mn2+ binding to mucilage and/or the cell wall.
The amount of loosely bound Mn2+ was significantly decreased after 24 h, whereas biomass
showed significant accumulation of Mn, O and P, as determined by energy dispersive X-ray
spectrometry, indicating the production of polyphosphates, which may sequester Mn. Further,
it was found that the exposure to Mn2+ resulted in rapid and transient decrease of total free
glutathione concentration; the drop was observed after 1 h, and the concentration returned to
initial values after 24 h. EPR measurements showed a similar trend in the level of reduced thiols.
The observed changes can be explained either by the synthesis of phytochelatins – sulfurrich
short-chain peptides that sequester metals, or by glutathionylation of proteins. Reduced
thiols could not be detected in the extracellular space, indicating that C. sorokiniana did not
release thiols in response to high Mn. These results demonstrate that the adaptive response
of C. sorokiniana to high Mn levels involves multiple components and time phases. The early
phase involves mucilage release, phytochelatins and/or protection of protein thiols, whereas
the successive phase involves Mn coordination by polyphosphates and other mechanisms that
remain to be resolved.
PB  - Elsevier
PB  - Society for Free Radical Research Europe (SFRR-E)
PB  - Ministry of Education, Science and Technological Development (Republic of Serbia)
PB  - Oxygen Club of California
C3  - Redox Biology in the 21st Century: A New Scientific Discipline, Meeting Abstracts
T1  - Mechanisms of detoxification of high manganese concentrations by the microalga Chlorella sorokiniana
EP  - 145
SP  - 145
DO  - 10.1016/j.freeradbiomed.2021.08.148
ER  - 

@conference{
author = "Vojvodić, Snežana and Stanić, Marina and Zechmann, Bernd and Dimitrijević, Milena and Opačić, Miloš and Danilović Luković, Jelena and Morina, Arian and Pittman, Jon K. and Spasojević, Ivan",
year = "2021",
abstract = "Many neutrophilic and acidophilic microalgal species tolerate high metal concentrations
and can survive or colonize metal-polluted waters. They show significant biotechnological
potential for the remediation and wastewaters processing. On the other hand, negative effects
of metal pollution on microalgae may affect the function of aquatic ecosystems because these
photosynthetic microorganisms represent the primary producers of O2 and biomass. However,
adaptive mechanisms that microalgae employ to detoxify metal excess are largely unknown.
Herein we analyzed the response of the freshwater microalga Chlorella sorokiniana to high
but non-toxic levels of Mn2+. Manganese is a key metal pollutant, with five possible oxidation
forms that can bind to a variety of different ligands. At pH below 7, it is predominantly present in
Mn2+ form. Scanning electron microscopy showed that in response to 1 mM Mn2+, C. sorokiniana
released mucilage polymers within 1 h. Electron paramagnetic resonance spectroscopy (EPR)
showed that the early response involved loose Mn2+ binding to mucilage and/or the cell wall.
The amount of loosely bound Mn2+ was significantly decreased after 24 h, whereas biomass
showed significant accumulation of Mn, O and P, as determined by energy dispersive X-ray
spectrometry, indicating the production of polyphosphates, which may sequester Mn. Further,
it was found that the exposure to Mn2+ resulted in rapid and transient decrease of total free
glutathione concentration; the drop was observed after 1 h, and the concentration returned to
initial values after 24 h. EPR measurements showed a similar trend in the level of reduced thiols.
The observed changes can be explained either by the synthesis of phytochelatins – sulfurrich
short-chain peptides that sequester metals, or by glutathionylation of proteins. Reduced
thiols could not be detected in the extracellular space, indicating that C. sorokiniana did not
release thiols in response to high Mn. These results demonstrate that the adaptive response
of C. sorokiniana to high Mn levels involves multiple components and time phases. The early
phase involves mucilage release, phytochelatins and/or protection of protein thiols, whereas
the successive phase involves Mn coordination by polyphosphates and other mechanisms that
remain to be resolved.",
publisher = "Elsevier, Society for Free Radical Research Europe (SFRR-E), Ministry of Education, Science and Technological Development (Republic of Serbia), Oxygen Club of California",
journal = "Redox Biology in the 21st Century: A New Scientific Discipline, Meeting Abstracts",
title = "Mechanisms of detoxification of high manganese concentrations by the microalga Chlorella sorokiniana",
pages = "145-145",
doi = "10.1016/j.freeradbiomed.2021.08.148"
}

Vojvodić, S., Stanić, M., Zechmann, B., Dimitrijević, M., Opačić, M., Danilović Luković, J., Morina, A., Pittman, J. K.,& Spasojević, I.. (2021). Mechanisms of detoxification of high manganese concentrations by the microalga Chlorella sorokiniana. in Redox Biology in the 21st Century: A New Scientific Discipline, Meeting Abstracts
Elsevier., 145-145.
https://doi.org/10.1016/j.freeradbiomed.2021.08.148

Vojvodić S, Stanić M, Zechmann B, Dimitrijević M, Opačić M, Danilović Luković J, Morina A, Pittman JK, Spasojević I. Mechanisms of detoxification of high manganese concentrations by the microalga Chlorella sorokiniana. in Redox Biology in the 21st Century: A New Scientific Discipline, Meeting Abstracts. 2021;:145-145.
doi:10.1016/j.freeradbiomed.2021.08.148 .

Vojvodić, Snežana, Stanić, Marina, Zechmann, Bernd, Dimitrijević, Milena, Opačić, Miloš, Danilović Luković, Jelena, Morina, Arian, Pittman, Jon K., Spasojević, Ivan, "Mechanisms of detoxification of high manganese concentrations by the microalga Chlorella sorokiniana" in Redox Biology in the 21st Century: A New Scientific Discipline, Meeting Abstracts (2021):145-145,
https://doi.org/10.1016/j.freeradbiomed.2021.08.148 . .

TY  - CONF
AU  - Dimitrijević, Milena
AU  - Vojvodić, Snežana
AU  - Opačić, Miloš
AU  - Danilović Luković, Jelena
AU  - Milić, Jelena
AU  - Stanić, Marina
AU  - Spasojević, Ivan
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2392
AB  - Microalgae show significant biotechnological potential for remediation of wastewaters polluted with metals, including nickel. Ni enters aquatic ecosystems from fuel combustion, smelting, mining, and electroplating endeavors, and represents a particularly important problem for the access to safe drinking water. It is noteworthy that microalgae utilize Ni as a co-factor of urease. Herein we analyzed the impact of high levels of Ni(II) on freshwater microalga Chlorella sorokiniana in the stationary phase of culture growth. In the concentration range 0.5 to 30 mM, Ni induced a drop in cell density and biomass after 7 days of incubation, whereas significant negative impact was present as early as 2 days for 30 mM. High concentrations also induced a decrease in the level of chlorophylls (a and b) in biomass. In contrast, microalgae that were exposed to moderate stress (1 and 2 mM of Ni) appear to increase photosynthetic activity, indicating the activation of some adaptive mechanism. Scanning electron microscopy showed that C. sorokiniana does not release significant amounts of mucilage polymers in response to Ni, in contrast to the response to some other metals 3. Further, Ni at 1 mM induced an increase in the intracellular production of reactive oxygen species, which appears to reach a plateau after 1 h. The concentration of free thiol groups showed a gradual drop during 24 h of incubation with the same Ni concentration. On the other hand, the decrease in the concentration of reduced glutathione that was observed after 1 h was reversible for 1 mM Ni at 24 h. Ni at 5 mM had a more lasting impact on glutathione. It is important to stress out that the concentrations of reduced glutathione and total glutathione showed very similar trends. This implies that free thiols and reduced glutathione may be ‘lost’ due to glutathionylation of proteins and synthesis of phytochelatins. Our results demonstrate that the response of C. sorokiniana to high Ni levels involves multiple components that may be different than for other metals. Redox regulation and protection of thiol (switches) may represent a crossroad between adaptation and death.
PB  - Faculty of Chemistry, Serbian Biochemical Society
C3  - Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia
T1  - The effect of increased nickel concentrations on Chlorella sorokiniana culture
EP  - 58
SP  - 57
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2392
ER  - 

@conference{
author = "Dimitrijević, Milena and Vojvodić, Snežana and Opačić, Miloš and Danilović Luković, Jelena and Milić, Jelena and Stanić, Marina and Spasojević, Ivan",
year = "2021",
abstract = "Microalgae show significant biotechnological potential for remediation of wastewaters polluted with metals, including nickel. Ni enters aquatic ecosystems from fuel combustion, smelting, mining, and electroplating endeavors, and represents a particularly important problem for the access to safe drinking water. It is noteworthy that microalgae utilize Ni as a co-factor of urease. Herein we analyzed the impact of high levels of Ni(II) on freshwater microalga Chlorella sorokiniana in the stationary phase of culture growth. In the concentration range 0.5 to 30 mM, Ni induced a drop in cell density and biomass after 7 days of incubation, whereas significant negative impact was present as early as 2 days for 30 mM. High concentrations also induced a decrease in the level of chlorophylls (a and b) in biomass. In contrast, microalgae that were exposed to moderate stress (1 and 2 mM of Ni) appear to increase photosynthetic activity, indicating the activation of some adaptive mechanism. Scanning electron microscopy showed that C. sorokiniana does not release significant amounts of mucilage polymers in response to Ni, in contrast to the response to some other metals 3. Further, Ni at 1 mM induced an increase in the intracellular production of reactive oxygen species, which appears to reach a plateau after 1 h. The concentration of free thiol groups showed a gradual drop during 24 h of incubation with the same Ni concentration. On the other hand, the decrease in the concentration of reduced glutathione that was observed after 1 h was reversible for 1 mM Ni at 24 h. Ni at 5 mM had a more lasting impact on glutathione. It is important to stress out that the concentrations of reduced glutathione and total glutathione showed very similar trends. This implies that free thiols and reduced glutathione may be ‘lost’ due to glutathionylation of proteins and synthesis of phytochelatins. Our results demonstrate that the response of C. sorokiniana to high Ni levels involves multiple components that may be different than for other metals. Redox regulation and protection of thiol (switches) may represent a crossroad between adaptation and death.",
publisher = "Faculty of Chemistry, Serbian Biochemical Society",
journal = "Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia",
title = "The effect of increased nickel concentrations on Chlorella sorokiniana culture",
pages = "58-57",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2392"
}

Dimitrijević, M., Vojvodić, S., Opačić, M., Danilović Luković, J., Milić, J., Stanić, M.,& Spasojević, I.. (2021). The effect of increased nickel concentrations on Chlorella sorokiniana culture. in Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia
Faculty of Chemistry, Serbian Biochemical Society., 57-58.
https://hdl.handle.net/21.15107/rcub_rimsi_2392

Dimitrijević M, Vojvodić S, Opačić M, Danilović Luković J, Milić J, Stanić M, Spasojević I. The effect of increased nickel concentrations on Chlorella sorokiniana culture. in Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia. 2021;:57-58.
https://hdl.handle.net/21.15107/rcub_rimsi_2392 .

Dimitrijević, Milena, Vojvodić, Snežana, Opačić, Miloš, Danilović Luković, Jelena, Milić, Jelena, Stanić, Marina, Spasojević, Ivan, "The effect of increased nickel concentrations on Chlorella sorokiniana culture" in Serbian Biochemical Society Tenth Conference, “Biochemical Insights into Molecular Mechanisms”. 24.09.2021. Kragujevac, Serbia (2021):57-58,
https://hdl.handle.net/21.15107/rcub_rimsi_2392 .

TY  - JOUR
AU  - Opačić, Miloš
AU  - Ristic, Aleksandar J
AU  - Sokic, Dragoslav
AU  - Baščarević, Vladimir
AU  - Raicević, Savo
AU  - Savić, Slobodan
AU  - Zorović, Maja
AU  - Zivin, Marko
AU  - Selih, Vid Simon
AU  - Spasojević, Ivan
AU  - Savić, Danijela Z
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1515
AB  - Introduction Disruption of copper homeostasis and dysfunction of mitochondria have been documented in sclerotic hippocampi (HS) of patients with mesial temporal lobe epilepsy (mTLE). However, a potential link between these pathological changes has not been tackled so far. Herein, we analyzed regional distribution of neuron somata density, copper concentration, and the activity of cytochrome c oxidase (CCO), a component of mitochondrial electron transport chain and copper-containing metalloprotein, in HS. Methods Histochemical staining and laser ablation inductively coupled plasma mass spectrometry were carried out to construct comparable maps of these parameters in coronal sections of hippocampi of 3 mTLE-HS patients and 3 control subjects. Results Copper levels were decreased in all regions of HS with pyramidal neuron somata. CCO activity was significantly reduced in stratum pyramidale (PY) 1 and cornu Ammonis field 4, the two regions with significant reduction in neuron somata density. CCO activity was also lower in layers that contain apical dendrites of pyramidal neurons and mossy fibers. It appears that copper deficiency in PY2 and PY3 comes before CCO activity reduction and neuronal loss. A strong positive correlation was found between neuron density, Cu concentration, and CCO activity. Conclusions Presented results imply that pathological alterations in Cu and energy metabolism could be involved in the development of HS. A limitation of this study was the relatively small number of patients. However, presented results underline copper deficiency as a component of pathological mechanisms of epilepsy and warrant further investigation of cuproproteins and members of copper transport machinery.
PB  - Wiley, Hoboken
T2  - Brain and Behavior
T1  - Regional distribution of cytochrome c oxidase activity and copper in sclerotic hippocampi of epilepsy patients
IS  - 2
VL  - 11
DO  - 10.1002/brb3.1986
ER  - 

@article{
author = "Opačić, Miloš and Ristic, Aleksandar J and Sokic, Dragoslav and Baščarević, Vladimir and Raicević, Savo and Savić, Slobodan and Zorović, Maja and Zivin, Marko and Selih, Vid Simon and Spasojević, Ivan and Savić, Danijela Z",
year = "2021",
abstract = "Introduction Disruption of copper homeostasis and dysfunction of mitochondria have been documented in sclerotic hippocampi (HS) of patients with mesial temporal lobe epilepsy (mTLE). However, a potential link between these pathological changes has not been tackled so far. Herein, we analyzed regional distribution of neuron somata density, copper concentration, and the activity of cytochrome c oxidase (CCO), a component of mitochondrial electron transport chain and copper-containing metalloprotein, in HS. Methods Histochemical staining and laser ablation inductively coupled plasma mass spectrometry were carried out to construct comparable maps of these parameters in coronal sections of hippocampi of 3 mTLE-HS patients and 3 control subjects. Results Copper levels were decreased in all regions of HS with pyramidal neuron somata. CCO activity was significantly reduced in stratum pyramidale (PY) 1 and cornu Ammonis field 4, the two regions with significant reduction in neuron somata density. CCO activity was also lower in layers that contain apical dendrites of pyramidal neurons and mossy fibers. It appears that copper deficiency in PY2 and PY3 comes before CCO activity reduction and neuronal loss. A strong positive correlation was found between neuron density, Cu concentration, and CCO activity. Conclusions Presented results imply that pathological alterations in Cu and energy metabolism could be involved in the development of HS. A limitation of this study was the relatively small number of patients. However, presented results underline copper deficiency as a component of pathological mechanisms of epilepsy and warrant further investigation of cuproproteins and members of copper transport machinery.",
publisher = "Wiley, Hoboken",
journal = "Brain and Behavior",
title = "Regional distribution of cytochrome c oxidase activity and copper in sclerotic hippocampi of epilepsy patients",
number = "2",
volume = "11",
doi = "10.1002/brb3.1986"
}

Opačić, M., Ristic, A. J., Sokic, D., Baščarević, V., Raicević, S., Savić, S., Zorović, M., Zivin, M., Selih, V. S., Spasojević, I.,& Savić, D. Z.. (2021). Regional distribution of cytochrome c oxidase activity and copper in sclerotic hippocampi of epilepsy patients. in Brain and Behavior
Wiley, Hoboken., 11(2).
https://doi.org/10.1002/brb3.1986

Opačić M, Ristic AJ, Sokic D, Baščarević V, Raicević S, Savić S, Zorović M, Zivin M, Selih VS, Spasojević I, Savić DZ. Regional distribution of cytochrome c oxidase activity and copper in sclerotic hippocampi of epilepsy patients. in Brain and Behavior. 2021;11(2).
doi:10.1002/brb3.1986 .

Opačić, Miloš, Ristic, Aleksandar J, Sokic, Dragoslav, Baščarević, Vladimir, Raicević, Savo, Savić, Slobodan, Zorović, Maja, Zivin, Marko, Selih, Vid Simon, Spasojević, Ivan, Savić, Danijela Z, "Regional distribution of cytochrome c oxidase activity and copper in sclerotic hippocampi of epilepsy patients" in Brain and Behavior, 11, no. 2 (2021),
https://doi.org/10.1002/brb3.1986 . .

TY  - CONF
AU  - Spasojević, Ivan
AU  - Stojiljković, Danica
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2412
AB  - Urbane sredine pokazuju značajno povišen nivo CO2 i čestičnih zagađivača koji su
povezani sa gustom naseljenošću, saobraćajem i brojnim funkcijama grada. U posebno ugroženim
mikrosredinama nije moguća primena standardnih načina ozelenjavanja, te su potrebna inovativna
rešenja. Jedno takvo rešenje je primena foto-bioreaktorskih sistema sa mikroalgama. Ovo rešenje je
zasnovano na eksploataciji visoke efikasnosti mikroalgi u vezivanju CO2 u odnosu na drveće i
travnjake, proizvodnji O2 i biomase, kao i filtracije vazduha kroz vodeni stub. Međutim,
biotehnološka komponenta iako ispunjava uslove za industrijske aplikacije, nije kompatibilna sa
urbanom primenom, već zahteva multifunkcionalnost, estetiku i izdržljivost. Na primeru urbanog
foto-bioreaktora LIQUID3 ovo je postignuto uklapanjem biotehnološke namene i urbanih funkcija -
urbani mobilijar, solarni punjač i ulična rasveta, savremenim dizajnom, i adekvatnim konstruktivnim
rešenjima. Održivost LIQUID3 sistema se postiže kroz pametno korišćenje urbanog prostora i kroz
proizvodnju biomase koja se koristi kao fertilizator. Multidisciplinarni pristup u razvoju ovog
alternativnog koncepta ozelenjavanja razvijenog i izvedenog u Srbiji, predstavlja osnovu njegove
funkcionalnosti i vijabilnosti u urbanom prostoru.
AB  - Urban environments show increased levels of CO2 and particulate matter that are related
to population density, intensive traffic, and numerous municipal functions. Some urban
microenvironments do not allow traditional greening and require innovative solutions, such as the
use of photo-bioreactors with microalgae. This alternative concept of greening exploits high
efficiency of microalgae in CO2 fixation and O2 and biomass production compared to trees and lawns,
as well as the filtration of air through water column. Although biotechnological component of this
concept meets the demands of industrial application, it is not per se compatible with the urban
application that calls for multifunctionality, aesthetics and robustness. In line with this, urban photobioreactor LIQUID3 combines biotechnological application and urban functions – bench, USB solar charger, and nightlight, with contemporary design and construction. Sustainability of LIQUID3 is achieved through smart use of city space and the production of biomass that can be used as
biofertilizer. Multidisciplinary approach in the development of alternative concepts of greening that
was developed and implemented in Serbia, represents the basis of its functionality and viability in
urban space.
PB  - Akademija tehničkih strukovnih studija Beograd
C3  - Šesti naučno-stručni skup POLITEHNIKA
T1  - Urbani foto-bioreaktor LIQUID3 – sinergija dizajna i biotehnologije
EP  - 909
SP  - 904
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2412
ER  - 

@conference{
author = "Spasojević, Ivan and Stojiljković, Danica",
year = "2021",
abstract = "Urbane sredine pokazuju značajno povišen nivo CO2 i čestičnih zagađivača koji su
povezani sa gustom naseljenošću, saobraćajem i brojnim funkcijama grada. U posebno ugroženim
mikrosredinama nije moguća primena standardnih načina ozelenjavanja, te su potrebna inovativna
rešenja. Jedno takvo rešenje je primena foto-bioreaktorskih sistema sa mikroalgama. Ovo rešenje je
zasnovano na eksploataciji visoke efikasnosti mikroalgi u vezivanju CO2 u odnosu na drveće i
travnjake, proizvodnji O2 i biomase, kao i filtracije vazduha kroz vodeni stub. Međutim,
biotehnološka komponenta iako ispunjava uslove za industrijske aplikacije, nije kompatibilna sa
urbanom primenom, već zahteva multifunkcionalnost, estetiku i izdržljivost. Na primeru urbanog
foto-bioreaktora LIQUID3 ovo je postignuto uklapanjem biotehnološke namene i urbanih funkcija -
urbani mobilijar, solarni punjač i ulična rasveta, savremenim dizajnom, i adekvatnim konstruktivnim
rešenjima. Održivost LIQUID3 sistema se postiže kroz pametno korišćenje urbanog prostora i kroz
proizvodnju biomase koja se koristi kao fertilizator. Multidisciplinarni pristup u razvoju ovog
alternativnog koncepta ozelenjavanja razvijenog i izvedenog u Srbiji, predstavlja osnovu njegove
funkcionalnosti i vijabilnosti u urbanom prostoru., Urban environments show increased levels of CO2 and particulate matter that are related
to population density, intensive traffic, and numerous municipal functions. Some urban
microenvironments do not allow traditional greening and require innovative solutions, such as the
use of photo-bioreactors with microalgae. This alternative concept of greening exploits high
efficiency of microalgae in CO2 fixation and O2 and biomass production compared to trees and lawns,
as well as the filtration of air through water column. Although biotechnological component of this
concept meets the demands of industrial application, it is not per se compatible with the urban
application that calls for multifunctionality, aesthetics and robustness. In line with this, urban photobioreactor LIQUID3 combines biotechnological application and urban functions – bench, USB solar charger, and nightlight, with contemporary design and construction. Sustainability of LIQUID3 is achieved through smart use of city space and the production of biomass that can be used as
biofertilizer. Multidisciplinary approach in the development of alternative concepts of greening that
was developed and implemented in Serbia, represents the basis of its functionality and viability in
urban space.",
publisher = "Akademija tehničkih strukovnih studija Beograd",
journal = "Šesti naučno-stručni skup POLITEHNIKA",
title = "Urbani foto-bioreaktor LIQUID3 – sinergija dizajna i biotehnologije",
pages = "909-904",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2412"
}

Spasojević, I.,& Stojiljković, D.. (2021). Urbani foto-bioreaktor LIQUID3 – sinergija dizajna i biotehnologije. in Šesti naučno-stručni skup POLITEHNIKA
Akademija tehničkih strukovnih studija Beograd., 904-909.
https://hdl.handle.net/21.15107/rcub_rimsi_2412

Spasojević I, Stojiljković D. Urbani foto-bioreaktor LIQUID3 – sinergija dizajna i biotehnologije. in Šesti naučno-stručni skup POLITEHNIKA. 2021;:904-909.
https://hdl.handle.net/21.15107/rcub_rimsi_2412 .

Spasojević, Ivan, Stojiljković, Danica, "Urbani foto-bioreaktor LIQUID3 – sinergija dizajna i biotehnologije" in Šesti naučno-stručni skup POLITEHNIKA (2021):904-909,
https://hdl.handle.net/21.15107/rcub_rimsi_2412 .

TY  - JOUR
AU  - Vojvodić, Snežana
AU  - Stanić, Marina
AU  - Zechmann, Bernd
AU  - Ducic, Tanja
AU  - Žižić, Milan
AU  - Dimitrijević, Milena
AU  - Danilović Luković, Jelena
AU  - Milenković, Milica R.
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1354
AB  - Microalgae have evolved mechanisms to respond to changes in copper ion availability, which are very important for normal cellular function, to tolerate metal pollution of aquatic ecosystems, and for modulation of copper bioavailability and toxicity to other organisms. Knowledge and application of these mechanisms will benefit the use of microalgae in wastewater processing and biomass production, and the use of copper compounds in the suppression of harmful algal blooms. Here, using electron microscopy, synchrotron radiation-based Fourier transform infrared spectroscopy, electron paramagnetic resonance spectroscopy, and X-ray absorption fine structure spectroscopy, we show that the microalga Chlorella sorokiniana responds promptly to Cu2+ at high non-toxic concentration, by mucilage release, alterations in the architecture of the outer cell wall layer and lipid structures, and polyphosphate accumulation within mucilage matrix. The main route of copper detoxification is by Cu2+ coordination to polyphosphates in penta-coordinated geometry. The sequestrated Cu2+ was accessible and could be released by extracellular chelating agents. Finally, the reduction in Cu2+ to Cu1+ appears also to take place. These findings reveal the biochemical basis of the capacity of microalgae to adapt to high external copper concentrations and to serve as both, sinks and pools of environmental copper.
PB  - Portland Press Ltd, London
T2  - Biochemical Journal
T1  - Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana
EP  - 3741
IS  - 19
SP  - 3729
VL  - 477
DO  - 10.1042/BCJ20200600
ER  - 

@article{
author = "Vojvodić, Snežana and Stanić, Marina and Zechmann, Bernd and Ducic, Tanja and Žižić, Milan and Dimitrijević, Milena and Danilović Luković, Jelena and Milenković, Milica R. and Pittman, Jon K. and Spasojević, Ivan",
year = "2020",
abstract = "Microalgae have evolved mechanisms to respond to changes in copper ion availability, which are very important for normal cellular function, to tolerate metal pollution of aquatic ecosystems, and for modulation of copper bioavailability and toxicity to other organisms. Knowledge and application of these mechanisms will benefit the use of microalgae in wastewater processing and biomass production, and the use of copper compounds in the suppression of harmful algal blooms. Here, using electron microscopy, synchrotron radiation-based Fourier transform infrared spectroscopy, electron paramagnetic resonance spectroscopy, and X-ray absorption fine structure spectroscopy, we show that the microalga Chlorella sorokiniana responds promptly to Cu2+ at high non-toxic concentration, by mucilage release, alterations in the architecture of the outer cell wall layer and lipid structures, and polyphosphate accumulation within mucilage matrix. The main route of copper detoxification is by Cu2+ coordination to polyphosphates in penta-coordinated geometry. The sequestrated Cu2+ was accessible and could be released by extracellular chelating agents. Finally, the reduction in Cu2+ to Cu1+ appears also to take place. These findings reveal the biochemical basis of the capacity of microalgae to adapt to high external copper concentrations and to serve as both, sinks and pools of environmental copper.",
publisher = "Portland Press Ltd, London",
journal = "Biochemical Journal",
title = "Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana",
pages = "3741-3729",
number = "19",
volume = "477",
doi = "10.1042/BCJ20200600"
}

Vojvodić, S., Stanić, M., Zechmann, B., Ducic, T., Žižić, M., Dimitrijević, M., Danilović Luković, J., Milenković, M. R., Pittman, J. K.,& Spasojević, I.. (2020). Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana. in Biochemical Journal
Portland Press Ltd, London., 477(19), 3729-3741.
https://doi.org/10.1042/BCJ20200600

Vojvodić S, Stanić M, Zechmann B, Ducic T, Žižić M, Dimitrijević M, Danilović Luković J, Milenković MR, Pittman JK, Spasojević I. Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana. in Biochemical Journal. 2020;477(19):3729-3741.
doi:10.1042/BCJ20200600 .

Vojvodić, Snežana, Stanić, Marina, Zechmann, Bernd, Ducic, Tanja, Žižić, Milan, Dimitrijević, Milena, Danilović Luković, Jelena, Milenković, Milica R., Pittman, Jon K., Spasojević, Ivan, "Mechanisms of detoxification of high copper concentrations by the microalga Chlorella sorokiniana" in Biochemical Journal, 477, no. 19 (2020):3729-3741,
https://doi.org/10.1042/BCJ20200600 . .

TY  - JOUR
AU  - Vojvodić, Snežana
AU  - Danilović Luković, Jelena
AU  - Zechmann, Bernd
AU  - Jevtović, Mima
AU  - Bogdanović Pristov, Jelena
AU  - Stanić, Marina
AU  - Lizzul, Alessandro Marco
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1371
AB  - The impact of ionizing radiation on microorganisms such as microalgae is a topic of increasing importance for understanding the dynamics of aquatic ecosystems in response to environmental radiation, and for the development of efficient approaches for bioremediation of mining and nuclear power plants wastewaters. Currently, nothing is known about the effects of ionizing radiation on the microalgal cell wall, which represents the first line of defence against chemical and physical environmental stresses. Using various microscopy, spectroscopy and biochemical techniques we show that the unicellular alga Chlorella sorokiniana elicits a fast response to ionizing radiation. Within one day after irradiation with doses of 1-5 Gy, the fibrilar layer of the cell wall became thicker, the fraction of uronic acids was higher, and the capacity to remove the main reactive product of water radiolysis increased. In addition, the isolated cell wall fraction showed significant binding capacity for Cu2+, Mn2+, and Cr3+. The irradiation further increased the binding capacity for Cu2+, which appears to be mainly bound to glucosamine moieties within a chitosan-like polymer in the outer rigid layer of the wall. These results imply that the cell wall represents a dynamic structure that is involved in the protective response of microalgae to ionizing radiation. It appears that microalgae may exhibit a significant control of metal mobility in aquatic ecosystems via biosorption by the cell wall matrix.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Chemosphere
T1  - The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana
VL  - 260
DO  - 10.1016/j.chemosphere.2020.127553
ER  - 

@article{
author = "Vojvodić, Snežana and Danilović Luković, Jelena and Zechmann, Bernd and Jevtović, Mima and Bogdanović Pristov, Jelena and Stanić, Marina and Lizzul, Alessandro Marco and Pittman, Jon K. and Spasojević, Ivan",
year = "2020",
abstract = "The impact of ionizing radiation on microorganisms such as microalgae is a topic of increasing importance for understanding the dynamics of aquatic ecosystems in response to environmental radiation, and for the development of efficient approaches for bioremediation of mining and nuclear power plants wastewaters. Currently, nothing is known about the effects of ionizing radiation on the microalgal cell wall, which represents the first line of defence against chemical and physical environmental stresses. Using various microscopy, spectroscopy and biochemical techniques we show that the unicellular alga Chlorella sorokiniana elicits a fast response to ionizing radiation. Within one day after irradiation with doses of 1-5 Gy, the fibrilar layer of the cell wall became thicker, the fraction of uronic acids was higher, and the capacity to remove the main reactive product of water radiolysis increased. In addition, the isolated cell wall fraction showed significant binding capacity for Cu2+, Mn2+, and Cr3+. The irradiation further increased the binding capacity for Cu2+, which appears to be mainly bound to glucosamine moieties within a chitosan-like polymer in the outer rigid layer of the wall. These results imply that the cell wall represents a dynamic structure that is involved in the protective response of microalgae to ionizing radiation. It appears that microalgae may exhibit a significant control of metal mobility in aquatic ecosystems via biosorption by the cell wall matrix.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Chemosphere",
title = "The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana",
volume = "260",
doi = "10.1016/j.chemosphere.2020.127553"
}

Vojvodić, S., Danilović Luković, J., Zechmann, B., Jevtović, M., Bogdanović Pristov, J., Stanić, M., Lizzul, A. M., Pittman, J. K.,& Spasojević, I.. (2020). The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana. in Chemosphere
Pergamon-Elsevier Science Ltd, Oxford., 260.
https://doi.org/10.1016/j.chemosphere.2020.127553

Vojvodić S, Danilović Luković J, Zechmann B, Jevtović M, Bogdanović Pristov J, Stanić M, Lizzul AM, Pittman JK, Spasojević I. The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana. in Chemosphere. 2020;260.
doi:10.1016/j.chemosphere.2020.127553 .

Vojvodić, Snežana, Danilović Luković, Jelena, Zechmann, Bernd, Jevtović, Mima, Bogdanović Pristov, Jelena, Stanić, Marina, Lizzul, Alessandro Marco, Pittman, Jon K., Spasojević, Ivan, "The effects of ionizing radiation on the structure and antioxidative and metal-binding capacity of the cell wall of microalga Chlorella sorokiniana" in Chemosphere, 260 (2020),
https://doi.org/10.1016/j.chemosphere.2020.127553 . .

TY  - JOUR
AU  - Korać Jačić, Jelena
AU  - Nikolić, Ljiljana M.
AU  - Stanković, Dalibor M.
AU  - Opačić, Miloš
AU  - Dimitrijević, Milena
AU  - Savić, Danijela Z
AU  - Grguric-Sipka, Sanja
AU  - Spasojević, Ivan
AU  - Bogdanović Pristov, Jelena
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1344
AB  - Upon release in response to stress, epinephrine (Epi) may interact with labile iron pool in human plasma with potentially important (patho)physiological consequences. We have shown that Epi and Fe3+ build stable 1:1 high-spin bidentate complex at physiological pH, and that Epi does not undergo degradation in the presence of iron. However, the interactions of Epi with the more soluble Fe2+, and the impact of iron on biological activity of Epi are still not known. Herein we showed that Epi and Fe2+ build colorless complex which is stable under anaerobic conditions. In the presence of O-2, Epi promoted the oxidation of Fe2+ and the formation of Epi-Fe3+ complex. Cyclic voltammetry showed that mid-point potential of Epi-Fe2+ complex is very low (-582 mV vs. standard hydrogen electrode), which explains catalyzed oxidation of Fe2+. Next, we examined the impact of iron binding on biological performance of Epi using patch clamping in cell culture with constitutive expression of adrenergic receptors. Epi alone evoked an increase of outward currents, whereas Epi in the complex with Fe3+ did not. This implies that the binding of Epi to adrenergic receptors and their activation is prevented by the formation of complex with iron. Pro-oxidative activity of Epi-Fe2+ complex may represent a link between chronic stress and cardiovascular problems. On the other hand, labile iron could serve as a modulator of biological activity of ligands. Such interactions may be important in human pathologies that are related to iron overload or deficiency.
PB  - Elsevier Science Inc, New York
T2  - Free Radical Biology and Medicine
T1  - Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors
EP  - 127
SP  - 123
VL  - 148
DO  - 10.1016/j.freeradbiomed.2020.01.001
ER  - 

@article{
author = "Korać Jačić, Jelena and Nikolić, Ljiljana M. and Stanković, Dalibor M. and Opačić, Miloš and Dimitrijević, Milena and Savić, Danijela Z and Grguric-Sipka, Sanja and Spasojević, Ivan and Bogdanović Pristov, Jelena",
year = "2020",
abstract = "Upon release in response to stress, epinephrine (Epi) may interact with labile iron pool in human plasma with potentially important (patho)physiological consequences. We have shown that Epi and Fe3+ build stable 1:1 high-spin bidentate complex at physiological pH, and that Epi does not undergo degradation in the presence of iron. However, the interactions of Epi with the more soluble Fe2+, and the impact of iron on biological activity of Epi are still not known. Herein we showed that Epi and Fe2+ build colorless complex which is stable under anaerobic conditions. In the presence of O-2, Epi promoted the oxidation of Fe2+ and the formation of Epi-Fe3+ complex. Cyclic voltammetry showed that mid-point potential of Epi-Fe2+ complex is very low (-582 mV vs. standard hydrogen electrode), which explains catalyzed oxidation of Fe2+. Next, we examined the impact of iron binding on biological performance of Epi using patch clamping in cell culture with constitutive expression of adrenergic receptors. Epi alone evoked an increase of outward currents, whereas Epi in the complex with Fe3+ did not. This implies that the binding of Epi to adrenergic receptors and their activation is prevented by the formation of complex with iron. Pro-oxidative activity of Epi-Fe2+ complex may represent a link between chronic stress and cardiovascular problems. On the other hand, labile iron could serve as a modulator of biological activity of ligands. Such interactions may be important in human pathologies that are related to iron overload or deficiency.",
publisher = "Elsevier Science Inc, New York",
journal = "Free Radical Biology and Medicine",
title = "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors",
pages = "127-123",
volume = "148",
doi = "10.1016/j.freeradbiomed.2020.01.001"
}

Korać Jačić, J., Nikolić, L. M., Stanković, D. M., Opačić, M., Dimitrijević, M., Savić, D. Z., Grguric-Sipka, S., Spasojević, I.,& Bogdanović Pristov, J.. (2020). Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors. in Free Radical Biology and Medicine
Elsevier Science Inc, New York., 148, 123-127.
https://doi.org/10.1016/j.freeradbiomed.2020.01.001

Korać Jačić J, Nikolić LM, Stanković DM, Opačić M, Dimitrijević M, Savić DZ, Grguric-Sipka S, Spasojević I, Bogdanović Pristov J. Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors. in Free Radical Biology and Medicine. 2020;148:123-127.
doi:10.1016/j.freeradbiomed.2020.01.001 .

Korać Jačić, Jelena, Nikolić, Ljiljana M., Stanković, Dalibor M., Opačić, Miloš, Dimitrijević, Milena, Savić, Danijela Z, Grguric-Sipka, Sanja, Spasojević, Ivan, Bogdanović Pristov, Jelena, "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors" in Free Radical Biology and Medicine, 148 (2020):123-127,
https://doi.org/10.1016/j.freeradbiomed.2020.01.001 . .

TY  - JOUR
AU  - Bogdanović Pristov, Jelena
AU  - Opačić, Miloš
AU  - Bajčetić, Milica
AU  - Mandic, Vesna
AU  - Maglic, Dragana
AU  - Miković, Zeljko
AU  - Spasojević, Ivan
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1316
AB  - Oxidative status of maternal blood represents an important parameter of pregnancy that is involved in both, regulation of physiological processes and (if significantly altered) development of different pregnancy complications. Inherited thrombophilias represent genetic disorders that increase the risk of thromboembolism in pregnancy. Little is known about the impact of thrombophilia on the oxidative status of maternal blood. In this study, we analyzed oxidative status of blood of 56 women with pregnancies burdened by inherited thrombophilias. The status was established at three different trimesters using biochemical assays and electrochemical measurements, and it was compared to 10 age- and trimester-matching controls. Activities of superoxide dismutase, catalase, and glutathione reductase in the 1(st)and the 2(nd)trimester of thrombophilic pregnancy were lower than controls. Also, there was less oxidation in the plasma, according to higher concentration of reduced thiols and lower oxidation-reduction potential. Therefore, it appears that thrombophilic mothers do not experience oxidative stress in the circulation in the first two trimesters. However, the rise in GPx, GR and SOD activities in the 3(rd)trimester of thrombophilic pregnancy implies that the risk of oxidative stress is increased during the late pregnancy. These results are important for developing antioxidative treatment that could tackle thrombophilia-related pregnancy complications.
PB  - Public Library Science, San Francisco
T2  - PLoS One
T1  - Oxidative status of maternal blood in pregnancies burdened by inherited thrombophilias
IS  - 6
VL  - 15
DO  - 10.1371/journal.pone.0234253
ER  - 

@article{
author = "Bogdanović Pristov, Jelena and Opačić, Miloš and Bajčetić, Milica and Mandic, Vesna and Maglic, Dragana and Miković, Zeljko and Spasojević, Ivan",
year = "2020",
abstract = "Oxidative status of maternal blood represents an important parameter of pregnancy that is involved in both, regulation of physiological processes and (if significantly altered) development of different pregnancy complications. Inherited thrombophilias represent genetic disorders that increase the risk of thromboembolism in pregnancy. Little is known about the impact of thrombophilia on the oxidative status of maternal blood. In this study, we analyzed oxidative status of blood of 56 women with pregnancies burdened by inherited thrombophilias. The status was established at three different trimesters using biochemical assays and electrochemical measurements, and it was compared to 10 age- and trimester-matching controls. Activities of superoxide dismutase, catalase, and glutathione reductase in the 1(st)and the 2(nd)trimester of thrombophilic pregnancy were lower than controls. Also, there was less oxidation in the plasma, according to higher concentration of reduced thiols and lower oxidation-reduction potential. Therefore, it appears that thrombophilic mothers do not experience oxidative stress in the circulation in the first two trimesters. However, the rise in GPx, GR and SOD activities in the 3(rd)trimester of thrombophilic pregnancy implies that the risk of oxidative stress is increased during the late pregnancy. These results are important for developing antioxidative treatment that could tackle thrombophilia-related pregnancy complications.",
publisher = "Public Library Science, San Francisco",
journal = "PLoS One",
title = "Oxidative status of maternal blood in pregnancies burdened by inherited thrombophilias",
number = "6",
volume = "15",
doi = "10.1371/journal.pone.0234253"
}

Bogdanović Pristov, J., Opačić, M., Bajčetić, M., Mandic, V., Maglic, D., Miković, Z.,& Spasojević, I.. (2020). Oxidative status of maternal blood in pregnancies burdened by inherited thrombophilias. in PLoS One
Public Library Science, San Francisco., 15(6).
https://doi.org/10.1371/journal.pone.0234253

Bogdanović Pristov J, Opačić M, Bajčetić M, Mandic V, Maglic D, Miković Z, Spasojević I. Oxidative status of maternal blood in pregnancies burdened by inherited thrombophilias. in PLoS One. 2020;15(6).
doi:10.1371/journal.pone.0234253 .

Bogdanović Pristov, Jelena, Opačić, Miloš, Bajčetić, Milica, Mandic, Vesna, Maglic, Dragana, Miković, Zeljko, Spasojević, Ivan, "Oxidative status of maternal blood in pregnancies burdened by inherited thrombophilias" in PLoS One, 15, no. 6 (2020),
https://doi.org/10.1371/journal.pone.0234253 . .

TY  - CONF
AU  - Dimitrijević, Milena
AU  - Bogdanović Pristov, Jelena
AU  - Žižić, Milan
AU  - Stanković, Dalibor
AU  - Bajuk-Bogdanović, Danica
AU  - Stanić, Marina
AU  - Hagen, Wilfred
AU  - Piccioli, Mario
AU  - Spasojević, Ivan
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/3187
AB  - The structure of biliverdin (BV) and its complexion capacity with Cu2+ in dependence of
solvent choice has been examined. We first examined coordinate/redox interactions of BV
with Cu2+ in phosphate buffer at pH 7.4, using spectrophotometry, HESI-MS, Raman
spectroscopy, 1HNMR, EPR, fluorimetry, and electrochemical methods. BV formed a stable
coordination complex with copper in 1 : 1 stoichiometry. The structure of BV was more
planar and energetically stable in the complex. The complex showed strong paramagnetic
effects that were attributed to an unpaired delocalized e−. The delocalized electron may come
from BV or Cu2+, so the complex is formally composed either of BV radical cation and Cu1+
or of BV radical anion and Cu3+. The complex underwent oxidation only in the presence of
both O2 and an excess of Cu2+, or a strong oxidizing agent, and it was resistant to reducing
agents. The biological effects of the stable BV metallocomplex containing a delocalized
unpaired electron should be further examined, and may provide an answer to the longstanding
question of high energy investment in the catabolism of BV, which represents a
relatively harmless molecule per se. The complex possibility was quite different after
changing the solvent. BV structure in DMSO was analyzed by using NMR techniques and
unrestricted density function theory simulations to explain the incapacity of BV to build
coordination complex(es) with Cu2+ in dimethyl sulfoxide, which was confirmed by UV-Vis,
EPR and NMR spectroscopy. NMR showed that N atoms of BV are protonated in all four
pyrrole rings. The structure is stabilized by two hydrogen bonds between NH moieties and
carbonyl oxygens from opposite terminal pyrrole rings, and by the bending of propionyl chain
with carboxyl group out of the plain toward central position of BV. The simulations of
deprotonated BV, which builds copper complexes in water and chloroform as described
previously, showed a different conformation and organization of hydrogen bonds. Taking into
account that deprotonation represents a critical step in coordinate bonds formation, the
protonation of an additional N atom may represent a key difference between the interactions
of BV with copper in different solvents.
PB  - COST Action CA15133
C3  - Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland
T1  - Structure of biliverdin and its interaction with copper
EP  - 44
SP  - 44
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_3187
ER  - 

@conference{
author = "Dimitrijević, Milena and Bogdanović Pristov, Jelena and Žižić, Milan and Stanković, Dalibor and Bajuk-Bogdanović, Danica and Stanić, Marina and Hagen, Wilfred and Piccioli, Mario and Spasojević, Ivan",
year = "2019",
abstract = "The structure of biliverdin (BV) and its complexion capacity with Cu2+ in dependence of
solvent choice has been examined. We first examined coordinate/redox interactions of BV
with Cu2+ in phosphate buffer at pH 7.4, using spectrophotometry, HESI-MS, Raman
spectroscopy, 1HNMR, EPR, fluorimetry, and electrochemical methods. BV formed a stable
coordination complex with copper in 1 : 1 stoichiometry. The structure of BV was more
planar and energetically stable in the complex. The complex showed strong paramagnetic
effects that were attributed to an unpaired delocalized e−. The delocalized electron may come
from BV or Cu2+, so the complex is formally composed either of BV radical cation and Cu1+
or of BV radical anion and Cu3+. The complex underwent oxidation only in the presence of
both O2 and an excess of Cu2+, or a strong oxidizing agent, and it was resistant to reducing
agents. The biological effects of the stable BV metallocomplex containing a delocalized
unpaired electron should be further examined, and may provide an answer to the longstanding
question of high energy investment in the catabolism of BV, which represents a
relatively harmless molecule per se. The complex possibility was quite different after
changing the solvent. BV structure in DMSO was analyzed by using NMR techniques and
unrestricted density function theory simulations to explain the incapacity of BV to build
coordination complex(es) with Cu2+ in dimethyl sulfoxide, which was confirmed by UV-Vis,
EPR and NMR spectroscopy. NMR showed that N atoms of BV are protonated in all four
pyrrole rings. The structure is stabilized by two hydrogen bonds between NH moieties and
carbonyl oxygens from opposite terminal pyrrole rings, and by the bending of propionyl chain
with carboxyl group out of the plain toward central position of BV. The simulations of
deprotonated BV, which builds copper complexes in water and chloroform as described
previously, showed a different conformation and organization of hydrogen bonds. Taking into
account that deprotonation represents a critical step in coordinate bonds formation, the
protonation of an additional N atom may represent a key difference between the interactions
of BV with copper in different solvents.",
publisher = "COST Action CA15133",
journal = "Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland",
title = "Structure of biliverdin and its interaction with copper",
pages = "44-44",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_3187"
}

Dimitrijević, M., Bogdanović Pristov, J., Žižić, M., Stanković, D., Bajuk-Bogdanović, D., Stanić, M., Hagen, W., Piccioli, M.,& Spasojević, I.. (2019). Structure of biliverdin and its interaction with copper. in Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland
COST Action CA15133., 44-44.
https://hdl.handle.net/21.15107/rcub_rimsi_3187

Dimitrijević M, Bogdanović Pristov J, Žižić M, Stanković D, Bajuk-Bogdanović D, Stanić M, Hagen W, Piccioli M, Spasojević I. Structure of biliverdin and its interaction with copper. in Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland. 2019;:44-44.
https://hdl.handle.net/21.15107/rcub_rimsi_3187 .

Dimitrijević, Milena, Bogdanović Pristov, Jelena, Žižić, Milan, Stanković, Dalibor, Bajuk-Bogdanović, Danica, Stanić, Marina, Hagen, Wilfred, Piccioli, Mario, Spasojević, Ivan, "Structure of biliverdin and its interaction with copper" in Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland (2019):44-44,
https://hdl.handle.net/21.15107/rcub_rimsi_3187 .

TY  - CONF
AU  - Bozic Cvijan, Bojana
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor
AU  - Stanić, Marina
AU  - Popovic Bijelic, Ana
AU  - Bogdanović Pristov, Jelena
AU  - Spasojević, Ivan
AU  - Bajcetic, Milica
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2847
AB  - Toxic effects of unconjugated bilirubin (BR) in neonatal hyperbilirubinemia have been related to redox and/or
coordinate interactions with Cu2+. However, the development and mechanisms of such interactions at physiological
pH have not been resolved. This study shows that BR reduces Cu2+ to Cu1+ in 1:1 stoichiometry.
Apparently, BR undergoes degradation, i.e. BR and Cu2+ do not form stable complexes. The binding of Cu2+ to
inorganic phosphates, liposomal phosphate groups, or to chelating drug penicillamine, impedes redox interactions
with BR. Cu1+ undergoes spontaneous oxidation by O2 resulting in hydrogen peroxide accumulation and
hydroxyl radical production. In relation to this, copper and BR induced synergistic oxidative/damaging effects
on erythrocytes membrane, which were alleviated by penicillamine. The production of reactive oxygen species
by BR and copper represents a plausible cause of BR toxic effects and cell damage in hyperbilirubinemia. Further
examination of therapeutic potentials of copper chelators in the treatment of severe neonatal hyperbilirubinemia
is needed.
PB  - Srpsko farmakološko društvo Beograd, Novi Sad
C3  - 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation
T1  - Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper
EP  - 242
SP  - 240
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2847
ER  - 

@conference{
author = "Bozic Cvijan, Bojana and Korać Jačić, Jelena and Stanković, Dalibor and Stanić, Marina and Popovic Bijelic, Ana and Bogdanović Pristov, Jelena and Spasojević, Ivan and Bajcetic, Milica",
year = "2019",
abstract = "Toxic effects of unconjugated bilirubin (BR) in neonatal hyperbilirubinemia have been related to redox and/or
coordinate interactions with Cu2+. However, the development and mechanisms of such interactions at physiological
pH have not been resolved. This study shows that BR reduces Cu2+ to Cu1+ in 1:1 stoichiometry.
Apparently, BR undergoes degradation, i.e. BR and Cu2+ do not form stable complexes. The binding of Cu2+ to
inorganic phosphates, liposomal phosphate groups, or to chelating drug penicillamine, impedes redox interactions
with BR. Cu1+ undergoes spontaneous oxidation by O2 resulting in hydrogen peroxide accumulation and
hydroxyl radical production. In relation to this, copper and BR induced synergistic oxidative/damaging effects
on erythrocytes membrane, which were alleviated by penicillamine. The production of reactive oxygen species
by BR and copper represents a plausible cause of BR toxic effects and cell damage in hyperbilirubinemia. Further
examination of therapeutic potentials of copper chelators in the treatment of severe neonatal hyperbilirubinemia
is needed.",
publisher = "Srpsko farmakološko društvo Beograd, Novi Sad",
journal = "14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation",
title = "Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper",
pages = "242-240",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2847"
}

Bozic Cvijan, B., Korać Jačić, J., Stanković, D., Stanić, M., Popovic Bijelic, A., Bogdanović Pristov, J., Spasojević, I.,& Bajcetic, M.. (2019). Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper. in 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation
Srpsko farmakološko društvo Beograd, Novi Sad., 240-242.
https://hdl.handle.net/21.15107/rcub_rimsi_2847

Bozic Cvijan B, Korać Jačić J, Stanković D, Stanić M, Popovic Bijelic A, Bogdanović Pristov J, Spasojević I, Bajcetic M. Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper. in 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation. 2019;:240-242.
https://hdl.handle.net/21.15107/rcub_rimsi_2847 .

Bozic Cvijan, Bojana, Korać Jačić, Jelena, Stanković, Dalibor, Stanić, Marina, Popovic Bijelic, Ana, Bogdanović Pristov, Jelena, Spasojević, Ivan, Bajcetic, Milica, "Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper" in 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation (2019):240-242,
https://hdl.handle.net/21.15107/rcub_rimsi_2847 .

TY  - CONF
AU  - Danilović Luković, Jelena
AU  - Zechmann, Bernd
AU  - Vojvodić, Snežana
AU  - Bogdanović Pristov, Jelena
AU  - Stanić, Marina
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2408
AB  - Cell wall of C. sorokiniana is composed of trilaminar sheath (TLS electron
translucent line inserted between two electron dense lines; the outermost layer is a mature mother
wall, while the thin inner layer is a daughter wall), and fibrilar cell wall. It is noteworthy that the
obtained diameters for untreated microalgae were in accordance with available data. The analysis of TEM micrographs showed that there were no significant changes in the thickness of
TLS for any of the used doses. However, the diameter of fibrillar wall was increased in response
to irradiation for microalgae exposed to 1 Gy and 2 Gy. The thickness of cell wall in microalgae
exposed to 5 Gy was not significantly different than in controls. A similar trend was
observed by gravimetry of dry cell wall isolates normalized to biomass. It is important to note that
no effects of radiation on biomass, at doses applied here, could be observed.
PB  - Institute for Biological Research “Siniša Stanković” and others contributors
C3  - 14th Multinational Congress on Microscopy. September 15–20, 2019, Belgrade, Serbia
T1  - The effects of ionizing radiation on the cell wall of microalgae Chlorella sorokiniana – TEM study
EP  - 153
SP  - 152
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2408
ER  - 

@conference{
author = "Danilović Luković, Jelena and Zechmann, Bernd and Vojvodić, Snežana and Bogdanović Pristov, Jelena and Stanić, Marina and Pittman, Jon K. and Spasojević, Ivan",
year = "2019",
abstract = "Cell wall of C. sorokiniana is composed of trilaminar sheath (TLS electron
translucent line inserted between two electron dense lines; the outermost layer is a mature mother
wall, while the thin inner layer is a daughter wall), and fibrilar cell wall. It is noteworthy that the
obtained diameters for untreated microalgae were in accordance with available data. The analysis of TEM micrographs showed that there were no significant changes in the thickness of
TLS for any of the used doses. However, the diameter of fibrillar wall was increased in response
to irradiation for microalgae exposed to 1 Gy and 2 Gy. The thickness of cell wall in microalgae
exposed to 5 Gy was not significantly different than in controls. A similar trend was
observed by gravimetry of dry cell wall isolates normalized to biomass. It is important to note that
no effects of radiation on biomass, at doses applied here, could be observed.",
publisher = "Institute for Biological Research “Siniša Stanković” and others contributors",
journal = "14th Multinational Congress on Microscopy. September 15–20, 2019, Belgrade, Serbia",
title = "The effects of ionizing radiation on the cell wall of microalgae Chlorella sorokiniana – TEM study",
pages = "153-152",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2408"
}

Danilović Luković, J., Zechmann, B., Vojvodić, S., Bogdanović Pristov, J., Stanić, M., Pittman, J. K.,& Spasojević, I.. (2019). The effects of ionizing radiation on the cell wall of microalgae Chlorella sorokiniana – TEM study. in 14th Multinational Congress on Microscopy. September 15–20, 2019, Belgrade, Serbia
Institute for Biological Research “Siniša Stanković” and others contributors., 152-153.
https://hdl.handle.net/21.15107/rcub_rimsi_2408

Danilović Luković J, Zechmann B, Vojvodić S, Bogdanović Pristov J, Stanić M, Pittman JK, Spasojević I. The effects of ionizing radiation on the cell wall of microalgae Chlorella sorokiniana – TEM study. in 14th Multinational Congress on Microscopy. September 15–20, 2019, Belgrade, Serbia. 2019;:152-153.
https://hdl.handle.net/21.15107/rcub_rimsi_2408 .

Danilović Luković, Jelena, Zechmann, Bernd, Vojvodić, Snežana, Bogdanović Pristov, Jelena, Stanić, Marina, Pittman, Jon K., Spasojević, Ivan, "The effects of ionizing radiation on the cell wall of microalgae Chlorella sorokiniana – TEM study" in 14th Multinational Congress on Microscopy. September 15–20, 2019, Belgrade, Serbia (2019):152-153,
https://hdl.handle.net/21.15107/rcub_rimsi_2408 .

TY  - CONF
AU  - Vojvodić, Snežana
AU  - Danilović Luković, Jelena
AU  - Zechmann, Bernd
AU  - Bogdanović Pristov, Jelena
AU  - Stanić, Marina
AU  - Pittman, Jon K.
AU  - Spasojević, Ivan
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2414
AB  - Microalgae are exposed to ionizing radiation from natural (e.g. radionuclides from the soil) and anthropogenic sources (such as radioactive waste, nuclear power accidents, etc). However, the mechanisms of adaptation to radiation are poorly understood. The aim of our study was to determine the effects of X-ray irradiation on the cell wall of Chlorella sorokiniana. C. sorokiniana (CCAP 211/8K) culture was grown in 3N-BBM+V medium, at 22°C with a continuous photon flux of 120 μmol m−2 s−1 for 20 days, reaching stationary phase. Cultures were then exposed to X-rays at doses of 1, 2 and 5 Gy, left under the same conditions for additional 24 h, and analyzed using TEM (postfixation with 1% osmium tetroxide, embedded in resin for soft blocks, and stained with uranyl acetate and lead acetate), and gravimetry. The analysis of TEM micrographs showed that there were no significant changes in the thickness of trilaminar sheath for any of the used doses. However, the diameter of the fibrillar wall was increased in response to irradiation: 105.5 ± 7.5 nm for untreated samples vs. 135.0 ± 9.5 nm (p = 0.015) for microalgae exposed to 1 Gy, and 127.9 ± 7.4 nm (p = 0.036) for exposure to 2 Gy. The thickness of the cell wall in microalgae exposed to 5 Gy (118.6 ± 8.6 nm) was not significantly different than in controls. A similar trend was observed by gravimetry of dry cell wall isolates normalized to biomass. It is important to note that no effects of radiation on biomass, at doses applied here, could be observed. It appears that Chlorella sorokiniana responds promptly to ionizing radiation by fortifying its ‘first line of defense’. The observed changes may be of particular interest for bioremediation, taking into account the capacity of the cell wall to bind water-soluble metals, including radionuclides.
PB  - Taylor & Francis Group
C3  - Journal of Experimental Botany
T1  - Adaptive response of Chlorella sorokiniana to ionizing radiation on the level of cell wall
EP  - 166
IS  - Supp 1
SP  - 166
VL  - 54
DO  - 10.1080/09670262.2019.1626628
ER  - 

@conference{
author = "Vojvodić, Snežana and Danilović Luković, Jelena and Zechmann, Bernd and Bogdanović Pristov, Jelena and Stanić, Marina and Pittman, Jon K. and Spasojević, Ivan",
year = "2019",
abstract = "Microalgae are exposed to ionizing radiation from natural (e.g. radionuclides from the soil) and anthropogenic sources (such as radioactive waste, nuclear power accidents, etc). However, the mechanisms of adaptation to radiation are poorly understood. The aim of our study was to determine the effects of X-ray irradiation on the cell wall of Chlorella sorokiniana. C. sorokiniana (CCAP 211/8K) culture was grown in 3N-BBM+V medium, at 22°C with a continuous photon flux of 120 μmol m−2 s−1 for 20 days, reaching stationary phase. Cultures were then exposed to X-rays at doses of 1, 2 and 5 Gy, left under the same conditions for additional 24 h, and analyzed using TEM (postfixation with 1% osmium tetroxide, embedded in resin for soft blocks, and stained with uranyl acetate and lead acetate), and gravimetry. The analysis of TEM micrographs showed that there were no significant changes in the thickness of trilaminar sheath for any of the used doses. However, the diameter of the fibrillar wall was increased in response to irradiation: 105.5 ± 7.5 nm for untreated samples vs. 135.0 ± 9.5 nm (p = 0.015) for microalgae exposed to 1 Gy, and 127.9 ± 7.4 nm (p = 0.036) for exposure to 2 Gy. The thickness of the cell wall in microalgae exposed to 5 Gy (118.6 ± 8.6 nm) was not significantly different than in controls. A similar trend was observed by gravimetry of dry cell wall isolates normalized to biomass. It is important to note that no effects of radiation on biomass, at doses applied here, could be observed. It appears that Chlorella sorokiniana responds promptly to ionizing radiation by fortifying its ‘first line of defense’. The observed changes may be of particular interest for bioremediation, taking into account the capacity of the cell wall to bind water-soluble metals, including radionuclides.",
publisher = "Taylor & Francis Group",
journal = "Journal of Experimental Botany",
title = "Adaptive response of Chlorella sorokiniana to ionizing radiation on the level of cell wall",
pages = "166-166",
number = "Supp 1",
volume = "54",
doi = "10.1080/09670262.2019.1626628"
}

Vojvodić, S., Danilović Luković, J., Zechmann, B., Bogdanović Pristov, J., Stanić, M., Pittman, J. K.,& Spasojević, I.. (2019). Adaptive response of Chlorella sorokiniana to ionizing radiation on the level of cell wall. in Journal of Experimental Botany
Taylor & Francis Group., 54(Supp 1), 166-166.
https://doi.org/10.1080/09670262.2019.1626628

Vojvodić S, Danilović Luković J, Zechmann B, Bogdanović Pristov J, Stanić M, Pittman JK, Spasojević I. Adaptive response of Chlorella sorokiniana to ionizing radiation on the level of cell wall. in Journal of Experimental Botany. 2019;54(Supp 1):166-166.
doi:10.1080/09670262.2019.1626628 .

Vojvodić, Snežana, Danilović Luković, Jelena, Zechmann, Bernd, Bogdanović Pristov, Jelena, Stanić, Marina, Pittman, Jon K., Spasojević, Ivan, "Adaptive response of Chlorella sorokiniana to ionizing radiation on the level of cell wall" in Journal of Experimental Botany, 54, no. Supp 1 (2019):166-166,
https://doi.org/10.1080/09670262.2019.1626628 . .