Isolation and characterization of a veratrol:corrinoid protein methyl transferase from Acetobacterium dehalogenans

摘要: From 3-methoxyphenol-grown cells of Acetobacterium dehalogenans, an inducible enzyme was purified that mediated the transfer methyl groups veratrol (1,2-dimethoxybenzene) to a corrinoid protein enriched from same cells. In this reaction, converted via 2-methoxyphenol 1,2-dihydroxybenzene. The veratrol:corrinoid transferase, designated MTIver, had apparent molecular mass about 32 kDa. With respect N-terminal amino acid sequence and other characteristics, MTIver is different vanillate:corrinoid transferase (MTIvan) isolated earlier bacterium. For tetrahydrofolate, two additional fractions were required, one which contained protein. This not identical with vanillate O-demethylase system. However, latter could also serve as acceptor for transferase. catalyzed demethylation veratrol, 3,4-dimethoxybenzoate, 2-methoxyphenol, 3-methoxyphenol. Vanillate (3-methoxy-4-hydroxybenzoate), 2-methoxybenzoate, or 4-methoxybenzoate substrates.