6-hydroxymellein O-methyltransferase () is an enzyme that catalyzes the chemical reaction
This is a methylation reaction in which the dihydroisocoumarin, (R)-6-hydroxymellein, is converted to the phytoalexin, (R)-6-methoxymellein. The methyl group comes from the cofactor, S-adenosyl methionine (SAM), which becomes S-adenosyl-L-homocysteine (SAH). The enzyme was characterised from carrots.
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:6-hydroxymellein 6-O-methyltransferase. This enzyme is also called 6-hydroxymellein methyltransferase.
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