Reaction: a demethylmenaquinone + S-adenosyl-L-methionine = a menaquinol + S-adenosyl-L-homocysteine
For diagram of reaction click here.
Other name(s): S-adenosyl-L-methioneDMK methyltransferase; demethylmenaquinone C-methylase; 2-heptaprenyl-1,4-naphthoquinone methyltransferase; 2-demethylmenaquinone methyltransferase; S-adenosyl-L-methione:2-demethylmenaquinone methyltransferase
Systematic name: S-adenosyl-L-methione:demethylmenaquinone methyltransferase
Comments: The enzyme catalyses the last step in menaquinone biosynthesis. It is able to accept substrates with varying polyprenyl side chain length (the chain length is determined by polyprenyl diphosphate synthase). The enzyme from Escherichia coli also catalyses the conversion of 2-methoxy-6-octaprenyl-1,4-benzoquinone to 5-methoxy-2-methyl-3-octaprenyl-1,4-benzoquinone during the biosynthesis of ubiquinone . The enzyme probably acts on menaquinol rather than menaquinone.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
1. Koike-Takeshita, A., Koyama, T. and Ogura, K. Identification of a novel gene cluster participating in menaquinone (vitamin K2) biosynthesis. Cloning and sequence determination of the 2-heptaprenyl-1,4-naphthoquinone methyltransferase gene of Bacillus stearothermophilus. J. Biol. Chem. 272 (1997) 12380-12383. [PMID: 9139683]
2. Wissenbach, U., Ternes, D. and Unden, G. An Escherichia coli mutant containing only demethylmenaquinone, but no menaquinone: effects on fumarate, dimethylsulfoxide, trimethylamine N-oxide and nitrate respiration. Arch. Microbiol. 158 (1992) 68-73. [PMID: 1444716]
3. Catala, F., Azerad, R. and Lederer, E. Sur les propriétés de la desméthylménaquinone C-méthylase de Mycobacterium phlei. Int. Z. Vitaminforsch. 40 (1970) 363-373. [PMID: 5450997]
4. Lee, P.T., Hsu, A.Y., Ha, H.T. and Clarke, C.F. A C-methyltransferase involved in both ubiquinone and menaquinone biosynthesis: isolation and identification of the Escherichia coli ubiE gene. J. Bacteriol. 179 (1997) 1748-1754. [PMID: 9045837]