[Structural changes of chloroplasts and galactolipid contents in Chlorella cells during clinorotation].

Research of chloroplast ultrastructure in Chlorella cells grown during long-term period under clinorotation has been carried out. Different changes of the chloroplast structure, concerning both the amount of starch grains and stroma electron density as well as membrane system have been revealed. Occurrence of more significant bends of the thylakoids compared to the control and more loose arrangement of the thylakoids in a bunch were noted. The most significant changes were observed in a membrane system, in particular, appearance of the non-uniform expansions of the inter- and intrathylakoid spaces in Chlorella chloroplasts. Taking into account the role of galactolipids as important components of the photosynthetic membranes, the content of general galactolipids, monogalactosyldiacylglycerol and digalactosyldiacylglicerol in Chlorella cells was determined. It was assumed that statistically significant increase of the galactolipid content, especially of MDG, can probably be one of the reasons of membrane system reorganizations in Chlorella cells under altered gravity.