Retired April 2012
Ph.D. 1970, University of Massachusetts, Amherst
Research Interests
Our research deals broadly with the origin, metabolism and function of terpenoids in plants, and more specifically with the monoterpene (C10), sesquiterpene (C15) and diterpene (C20) constituents of the essential oils and resins used in pharmaceuticals, nutraceuticals, flavors, fragrances, and as industrial raw materials. These low molecular weight terpenoids provide a means of chemical defense and communication in plants, yet these compounds are also catabolized during development, suggesting a metabolic role in addition to the ecological function.
Specific areas of investigation include: the structure and mechanism of the enzymes of terpenoid biosynthesis and catabolism; the molecular regulation of metabolism directed toward improved production of terpenoids as petrochemical replacements; the genetic and biochemical origins of terpenoid phytoalexins and phytotoxins, and the mechanism of induced conifer resistance to bark beetle infestation; the biochemical basis of developmental and environmental influences on the composition and yield of commercial terpenoid products (oils, resins, waxes); and biological and molecular approaches (cell cultures, immobilized enzymes, catalytically-modified proteins, transgenic plants) to industrial-scale production of terpenoid compounds of agrochemical and pharmaceutical significance, including taxol.
Diagrams
Crystal structure of bornyl diphosphate synthase ( bdps ) that catalyzes the monoterpene cyclization of geranyl diphosphate to bornyl diphosphate, the precursor of camphor.
The committed diterpenoid precursor taxadiene is converted to the anticancer drug Taxol ( RCwebtax ) by a series of hydroxylation and acylation reactions.
The organization of monoterpene biosynthesis ( terpenesinacell ) in the oil glands of peppermint is complex in involving plastidial endoplasmic reticulum, mitochondrial and cytosolic sites of metabolism.