Biosynthesis of the major scent components 3,5-dimethoxytoluene and 1,3,5-trimethoxybenzene by novel rose O-methyltransferases.

In Chinese rose species and in many modern varieties, two methylated phenolic derivatives, 3,5-dimethoxytoluene and 1,3,5-trimethoxybenzene, are major scent components. We show that cell-free extracts of rose petals catalyse the synthesis of 3,5-dimethoxytoluene and 1,3,5-trimethoxybenzene by methylation of precursor molecules. An expressed sequence tag approach was used to identify four highly similar O-methyltransferase sequences expressed specifically in petals and anthers.