Identifying Substrates and Products of Enzymes of Plant Volatile Biosynthesis with the Help of Metabolic Profiling

Ongoing efforts in metabolic profiling of both cultivated and wild plants continue to identify new plant compounds, many of them unique to a single species or found only in closely related species. Such compounds are defined as specialized, or secondary, metabolites and they play many physiological and ecological roles, including in plant-insect and plant-pathogen interactions. To date, only a few of the enzymatic reactions leading to the synthesis of such compounds have been elucidated and the enzymes responsible identified. Our group has concentrated on the biosynthesis of plant volatiles. We present several examples in which metabolic profiling together with gene expression profiling and biochemical methods have led to the identification of enzymes responsible for the synthesis of volatile terpenes in Arabidopsis flowers, benzenoid esters in Arabidopsis leaves, and terpenes and methylated phenylpropenes in glands of sweet basil.