2mad
From Proteopedia
THE ACTIVE SITE STRUCTURE OF METHYLAMINE DEHYDROGENASE: HYDRAZINES IDENTIFY C6 AS THE REACTIVE SITE OF THE TRYPTOPHAN DERIVED QUINONE COFACTOR
Structural highlights
FunctionDHML_PARVE Methylamine dehydrogenase carries out the oxidation of methylamine. Electrons are passed from methylamine dehydrogenase to amicyanin. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedTo identify the reactive part of the orthoquinone function of the tryptophan-derived cofactor found in methylamine dehydrogenase (MADH), we have determined the crystal structures of MADH from Thiobacillus versutus inhibited by methylhydrazine and (2,2,2-trifluoroethyl)hydrazine. Extra electron density attached to C6 of the tryptophyl tryptophanquinone cofactor shows that this atom and not C7 is the reactive part of the ortho-quinone moiety. The density retained after hydrazine inhibition is much less extensive than expected, however, suggesting that partial breakdown of the inhibitors after reaction with the cofactor may take place. A detailed description is presented of the cofactor environment in an improved model of MADH which now includes information from the recently determined gene sequence of the cofactor-containing subunit [Ubbink, M., van Kleef, M.A.G., Kleinjan, D., Hoitink, C.W.G., Huitema, F., Beintema, J.J., Duine, J.A., & Canters, G.W. (1991) Eur. J. Biochem. 202, 1003-1012]. We hypothesize that Asp76 is responsible for proton abstraction from the alpha-carbon of the substrate during catalysis. 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[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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