Monolignin alcohols (type H, type G and type S) are the basic units of lignin and lignans in plants, and their composition differences directly determine the chemical diversity and biological activity of lignin and lignans. Caffeic acid O-methyltransferase (COMT) catalyzes the methylation of oxygen atoms on the hydroxyl groups of phenylpropanoids, playing a critical role in the composition of different types of monolignin alcohols, and thus acting as a key enzyme involved in the biosynthesis pathway of lignin and lignans. A previous review published in 2010 mainly introduced the gene characteristics of COMT and its regulatory role in lignin biosynthesis. This article summarized the latest research progress of COMT in the past decade, including the gene characteristics, expression characteristics, structural characteristics of COMT and its regulatory effects, and prospected future research and application of COMT.
Keywords: caffeic acid O-methyltransferase; lignans; lignin; monolignin alcohol.