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

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 (α, β and γ chains) with associated bacteriochlorophyll b s 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 P 1, with unit‐cell parameters a = 141.4, b = 136.9, c = 185.3 Å, α = 104.6, β = 94.0, γ = 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.