Subunit composition of CP43-less photosystem II complexes of Synechocystis sp PCC 6803: implications for the assembly and repair of photosystem II

0388812 - MBÚ 2013 RIV GB eng J - Journal Article
Boehm, M. - Yu, J. - Reisinger, V. - Bečková, Martina - Eichacker, L. A. - Schlodder, E. - Komenda, Josef - Nixon, P. J.
Subunit composition of CP43-less photosystem II complexes of Synechocystis sp PCC 6803: implications for the assembly and repair of photosystem II.
Philosophical Transactions of the Royal Society B-Biological Sciences. Roč. 367, č. 1608 (2012), s. 3444-3454. ISSN 0962-8436. E-ISSN 1471-2970
R&D Projects: GA ČR(CZ) GAP501/11/0377; GA MŠMT(CZ) ED2.1.00/03.0110
Institutional support: RVO:61388971
Keywords : Synechocystis * RC47 * low-molecular-mass subunit
Subject RIV: EE - Microbiology, Virology
Impact factor: 6.230, year: 2012

Photosystem II (PSII) mutants are useful experimental tools to trap potential intermediates involved in the assembly of the oxygen-evolving PSII complex. Here, we focus on the subunit composition of the RC47 assembly complex that accumulates in a psbC null mutant of the cyanobacterium Synechocystis sp. PCC 6803 unable to make the CP43 apopolypeptide. By using native gel electrophoresis, we showed that RC47 is heterogeneous and mainly found as a monomer of 220 kDa. RC47 complexes co-purify with small Cab-like proteins (ScpC and/or ScpD) and with Psb28 and its homologue Psb28-2. Analysis of isolated His-tagged RC47 indicated the presence of D1, D2, the CP47 apopolypeptide, plus nine of the 13 low-molecular-mass (LMM) subunits found in the PSII holoenzyme, including PsbL, PsbM and PsbT, which lie at the interface between the two momomers in the dimeric holoenzyme. Not detected were the LMM subunits (PsbK, PsbZ, Psb30 and PsbJ) located in the vicinity of CP43 in the holoenzyme. The photochemical activity of isolated RC47-His complexes, including the rate of reduction of P680(+), was similar to that of PSII complexes lacking the Mn4CaO5 cluster. The implications of our results for the assembly and repair of PSII in vivo are discussed
Permanent Link: http://hdl.handle.net/11104/0217726