Biochemical and molecular genetic aspects of floral scents.

The chemical composition of floral scents has been extensively investigated for hundreds of years because of the commercial value of floral volatiles in perfumery. More recently, several ecological studies have examined the roles of floral scent in the biology of the plant. However, in contrast to the chemical emphasis of the perfumers and the organismal emphasis of the ecologists, until recently, there have been few studies concerning the biochemical synthesis of floral scent compounds and the enzymes and genes that control these processes. In fact, our recent investigation into the biogenesis of floral scent production in Clarkia breweri, an annual plant native to California that served as our model organism, and our even more recent work on the scent of the cultivated snapdragon (Antirrhinum majus) represent the only examples to date (to our knowledge) in which isolation of enzymes and genes involved in the de novo synthesis of scent compounds in the flower have been reported. In this Update we review the research leading to our work, report our findings, and discuss implications for future directions of the field.