Isotope Labeling Studies Reveal the Order of Oxygen Incorporation into the Tryptophan Tryptophylquinone Cofactor of Methylamine Dehydrogenase

摘要

An increasing number of enzymes of eukaryotic and prokaryotic origin have been shown to contain novel cofactors derived from endogenous amino acids.Many of these protein-derived cofactors are formed autocatalytically.The tryptophan tryptophylquinone(TTQ)cofactor of methylamine dehydrogenase(MADH)is different in that formation of active enzyme requires co-expression of four processing genes,including mauG,which encodes a di-heme c-type cytochrome with unusual properties.