Abstract
Phosphatidylglycerol (PG) is the only phospholipid in thylakoid membranes, which are the site of primary reactions of photosynthesis. We previously isolated a pgsA mutant of Synechocystis sp. PCC 6803 defective in biosynthesis of PG. With the mutant we have already demonstrated that PG plays important roles in electron transport in the photosystem II (PS II) complex.
In this study, we purified the PSII complex from the pgsA mutant and analyzed its subunit composition to clarify the role of PG in assembly of the PSII complex. Compared to the subunits in the PSII complex purified from the wild type cells, it was found that some subunits were not present in the PSII complexes of the mutant and some subunits were only present in that of the mutant. These proteins were identified by MALDI-TOF MS, and the role of PG in assembly of the PSII complexes has been investigated.
