Requires Mg2+. The 2-hydroxy group of a 6-deoxy-D-allose residue in demethylmacrocin acts as a methyl acceptor. Isolated from Streptomyces fradiae. Also acts on demethyllactenocin giving lactenocin. Involved in the biosynthesis of the macrolide antibiotic tylosin. Not identical with EC 2.1.1.101 macrocin O-methyltransferase.