4RCR:
reference: Structure of the reaction center from Rhodobacter sphaeroides R-26 and 2.4.1: protein-cofactor (bacteriochlorophyll, bacteriopheophytin, and carotenoid) interactions., Yeates TO, Komiya H, Chirino A, Rees DC, Allen JP, Feher G, Proc Natl Acad Sci U S A 1988 Nov;85(21):7993-7. PMID: 3186702

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