1FWX:
reference: Revisiting the catalytic CuZ cluster of nitrous oxide (N2O) reductase. Evidence of a bridging inorganic sulfur., Brown K, Djinovic-Carugo K, Haltia T, Cabrito I, Saraste M, Moura JJ, Moura I, Tegoni M, Cambillau C, J Biol Chem 2000 Dec 29;275(52):41133-6. PMID: 11024061

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