electron transport processes

Thylakoid membranes in chloroplasts and cyanobacterial cells are the sites of the primary processes of oxygenic photosynthesis. The lipid composition of thylakoid mem-branes is highly conserved and consists of mostly glycolipids and about 10 % phosphatidylglycerol (PG) as the only phospholipid. PG is considered to play an important role in the ordered assembly and structural maintenance of the photosynthetic apparatus. In order to investigate the function of PG in the photo-synthetic electron transport processes we studied a pgsA– mutant which was constructed from a cyanobacterial strain, Synechocystis PCC 6803. This mutant is defective in PG phos-phate synthase gene, and it is incapable of synthesizing PG and requires PG supplementation for growth. The depri-vation of PG from the growth medium decreased the P