Acta Crystallographica Section F

Structural Biology and Crystallization Communications

Volume 61, Part 1 (January 2005)

crystallization communications

Acta Cryst. (2005). F61, 83-86 [ doi:10.1107/S1744309104028945 ]

Crystallization and preliminary X-ray studies on the reaction center-light-harvesting 1 core complex from Rhodopseudomonas viridis

S. Saijo, T. Sato, T. Kumasaka, N. Tanaka, K. Harata and T. Odahara

Abstract: The reaction center-light-harvesting 1 (RC-LH1) core complex is the photosynthetic apparatus in the membrane of the purple photosynthetic bacterium Rhodopseudomonas viridis. The RC is surrounded by an LH1 complex that is constituted of oligomers of three types of apoproteins ( [alpha] , [beta] and [gamma] chains) with associated bacteriochlorophyll bs and carotenoid. It has been crystallized by the sitting-drop vapour-diffusion method. A promising crystal diffracted to beyond 8.0 Å resolution. It belonged to space group P1, with unit-cell parameters a = 141.4, b = 136.9, c = 185.3 Å, [alpha] = 104.6, [beta] = 94.0, [gamma] = 110.7°. A Patterson function calculated using data between 15.0 and 8.0 Å resolution suggested that the LH1 complex is distributed with quasi-16-fold rotational symmetry around the RC.

Keywords: photosynthesis; reaction center-light-harvesting 1 core complex; Rhodopseudomonas viridis; integral membrane proteins.