3AYF:
reference: Crystal structure of quinol-dependent nitric oxide reductase from Geobacillus stearothermophilus., Matsumoto Y, Tosha T, Pisliakov AV, Hino T, Sugimoto H, Nagano S, Sugita Y, Shiro Y, Nat Struct Mol Biol. 2012 Jan 22;19(2):238-45. doi: 10.1038/nsmb.2213. PMID: 22266822

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