@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"
}