Rhodopseudomonas viridis photosynthetic reaction centre

Deisenhofer, J., Epp, O., Miki, K., Huber, R., and Michel, H. Structure of the protein subunits in the photosynthetic reaction centre of Rhodopseudomonas viridis at 3 A resolution (1985) Nature 318, 618-624... 

Deisenhofer, J., and H. Michel, The photosynthetic reaction centre from the purple bacterium Rhodopseudomonas viridis. Science 245 1463, 1989. The structure of abacterial reaction center is revealed by x-ray crystallography. 

H Michel (1982) Three-dimensional crystals of a membrane protein complex. The photosynthetic reaction centre from Rhodopseudomonas viridis. J Mol Biol 158 567-572... 

H Michel, 0 Epp and J Deisenhofer (1986) Pigment-protein interactions in the photosynthetic reaction centre from Rhodopseudomonas viridis. EMBO J 5 2445-2451... 

Deisenhofer, J. Michel, H. "The Photosynthetic Reaction Centre From the Purple Bacterium Rhodopseudomonas viridis," MBO J. 1989,8,2149-2170. 

The photosynthetic reaction centres (RCs) are transmembrane protein-pigment complexes that perform light-induced charge separation during the primary steps of photosynthesis. RCs from purple bacteria consist of three protein subunits, L, M and H, and bind four bacteriochlorophylls, two bacteriopheophytins, two quinones, one non-haem iron and one carotenoid. The elucidation at atomic resolution of the three-dimensional structures of the bacterial RCs from Rhodopseudomonas (Rps.) viridis (1) and Rhodobacter (Rb,) sphaeroides (2-4) has provided impetus for theoretical and experimental work on the mechanism of primary charge separation in the RCs. The structures revealed that the cofactors are bound at the interface between the L and M subunits and are organised around a pseudo C2 symmetry axis. However, the structural symmetry does not result in functional symmetry as the electron transfer proceeds only along the L branch (5). 

Michel H and Deisenhofer J (1988) Relevance of the photosynthetic reaction center from purple bacteria to the structure of Photosystem II. Biochemistry 27 1-7 Michel H, Weyer KA, Gruenberg K, Dunger I, Oesterhelt D and Lottspeich F (1986a) The Tight and medium subunits of the photosynthetic reaction centre from Rhodopseudomonas viridis Isolation of the genes, nucleotide and amino acid sequence. EMBOJ5 1149-1158... 

The photochemically active pigments of photosystem II (PSII) are housed in an apoprotein environment provided by the D1 and D2 polypeptides which also contain binding sites for the acceptor quinones (Q and Q ). The organisation of the polypeptides and chromophores has been inferred (1-3) from various similarities and homologies between PSII reaction centres and the photosynthetic reaction centres of purple bacteria, such as Rhodopseudomonas viridis, which have been structurally resolved in considerable detail (e.g. 4). By analogy with the L and M polypeptides of bacterial reaction centres, D1 and D2 each contain 5 transmembrane helical spans. There is strong sequence homology... 

The larger part of research on light-driven eleetron transfer in purple photosynthetic bacteria has involved three speeies, Rhodopseudomonas (Rps.) viridis, Rhodobacter (Rb.) sphaeroides and Rb. capsulatus. The bulk of this article is written in reference to the Rb. sphaeroides reaetion eentre, the subject of the majority of spectroscopic and mutagenesis work earried out to date. However, much of the research described below has involved the reaction centre from Rb. capsulatus or Rps. viridis, or reaetion eentres from other species of purple bacteria. 

Lancaster CRD, ErmlerU and Michel H (1995) The structures of photosynthetic reaction centers from purple bacteria as revealed by X-ray crystallography. In Blankenship RE, Madigan MT and Bauer CE (eds) Anoxygenic Photosynthetic Bacteria, pp 503-526. Kluwer Academic Publishers, Dordrecht Lancaster CRD, Michel H, Honig B and Gunner MR (1996) Calculated coupling of electron and proton transfer in the photosyntheticreaction centre of Rhodopseudomonas viridis. Biophys 1 70 2469-2492... 

The primary electron transfer event in photosynthesis is the transfer of an electron from the excited state reaction centre chlorophyll [P]to pheophytin [I]. This charge separation is then stabilised by transfer of the electron to a chain of acceptors and the rereduction of the reaction centre chlorophyll by an electron donor. In the purple photosynthetic bacterium Rhodopseudomonas viridis the electron acceptors are quinones and the electron donors are cytochrome haems. The acceptor complex is thought to consist of a primary quinone [Qa], which is a menaquinone, and a secondary quinone [Qb], which is ubiquinone. Qa is tightly bound to the reaction centre and undergoes... 

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