1FFT:
reference: The structure of the ubiquinol oxidase from Escherichia coli and its ubiquinone binding site., Abramson J, Riistama S, Larsson G, Jasaitis A, Svensson-Ek M, Laakkonen L, Puustinen A, Iwata S, Wikstrom M, Nat Struct Biol 2000 Oct;7(10):910-7. PMID: 11017202

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