3OM3:
reference: Crystallographic and online spectral evidence for role of conformational change and conserved water in cytochrome oxidase proton pump., Liu J, Qin L, Ferguson-Miller S, Proc Natl Acad Sci U S A. 2011 Jan 25;108(4):1284-9. Epub 2011 Jan 4. PMID: 21205904

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