3K9Z:
reference: Rational design of a structural and functional nitric oxide reductase., Yeung N, Lin YW, Gao YG, Zhao X, Russell BS, Lei L, Miner KD, Robinson H, Lu Y, Nature. 2009 Dec 24;462(7276):1079-82. Epub 2009 Nov 25. PMID: 19940850

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