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Updated: Aug 11, 2026

On-Chip Crystallization and Large-Scale Serial Diffraction at Room Temperature
Published on: March 11, 2022
Crystallization and preliminary X-ray studies on the reaction center-light-harvesting 1 core complex from
Shinya Saijo1, Takao Sato, Takashi Kumasaka
1Department of Life Science, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
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 A resolution. It belonged to space group P1, with unit-cell parameters a = 141.4, b = 136.9, c = 185.3 A, alpha = 104.6, beta = 94.0, gamma = 110.7 degrees. A Patterson function calculated using data between 15.0 and 8.0 A resolution suggested that the LH1 complex is distributed with quasi-16-fold rotational symmetry around the RC.
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