2MAD:
reference: Active site structure of methylamine dehydrogenase: hydrazines identify C6 as the reactive site of the tryptophan-derived quinone cofactor., Huizinga EG, van Zanten BA, Duine JA, Jongejan JA, Huitema F, Wilson KS, Hol WG, Biochemistry 1992 Oct 13;31(40):9789-95. PMID: 1390754

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