ID 2.1.1.365 DE MMP 1-O-methyltransferase. AN 3-O-methylmannose polysaccharide 1-O-methyltransferase. CA 3,3'-di-O-methyl-4alpha-mannobiose + S-adenosyl-L-methionine = CA 1,3,3'-tri-O-methyl-4alpha-mannobiose + H(+) + S-adenosyl-L-homocysteine. CC -!- Requires Mg(2+). CC -!- The enzyme, characterized from the bacterium Mycolicibacterium CC hassiacum, participates in the biosynthesis of 3-O-methylmannose CC polysaccharides (MMP), which are intracellular polymethylated CC polysaccharides implicated in the modulation of fatty acid metabolism CC in non-tuberculous mycobacteria. CC -!- The methylation catalyzed by this enzyme was shown to block the CC reducing end of 3,3'-di-O-methyl-alpha-mannobiose, a probable early CC precursor of the 3-O-methylmannose polysaccharides. DR K5B7F3, MET1_MYCHD ; //