In enzymology, a demethylmacrocin O-methyltransferase (EC 220.127.116.11) is an enzyme that catalyzes the chemical reaction
S-adenosyl-L-methionine + demethylmacrocin
S-adenosyl-L-homocysteine + macrocin
Thus, the two substrates of this enzyme are S-adenosyl methionine and demethylmacrocin, whereas its two products are S-adenosylhomocysteine and macrocin.
This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:demethylmacrocin 2"'-O-methyltransferase. This enzyme is also called demethylmacrocin methyltransferase. This enzyme participates in biosynthesis of 12-, 14- and 16-membered macrolides.