I received an M.Sc. and Ph.D. in molecular biology through the Department of Molecular, Cellular, and Developmental Biology at the University of Michigan, Ann Arbor. My Master's work focused on possible methods for improving the biosynthesis of the cancer-fighting diterpene, taxol, in Taxus species in the laboratory of Dr. Peter Kaufman. This, combined with my dissertation research on the molecular biology and biotechnological application of terpenoid scent compound production, stimulated my interest in plant secondary metabolism. I have also worked in the Department of Plant Sciences at the University of Arizona, Tucson, in the laboratory of Dr. Rich Jorgensen where I worked to elucidate the factors involved in gene suppression of anthocyanin biosynthesis. My collaboration with Dr. Kaufman continues to this day, and our latest project involves the preparation of the seconded edition of our book entitled "Natural Products from Plants" from CRC Press. (see the link below).

Unraveling the Biosynthesis and Molecular Regulation of Plant Secondary Metabolism
     Plants are an important source of natural medicinal compounds. While plant natural products hold a great deal of potential use for many human ailments, they are often made in only trace amounts within the specific species that produce them. For years, researchers have suggested that plants and cell cultures grown under controlled conditions may hold the key to mass production of specific medicinal compounds. However, past attempts at stimulating the synthesis of large amounts of products from such systems have only been marginally successful, primarily due to the lack of information surrounding the genes, regulators, and rate-limiting enzymes found within a diverse network of biosynthetic pathways. In addition, no systems to date have given researchers a clear way to identify the key regulatory genes active in cell suspension cultures versus whole plant cultures. In our research, we attempt to address the study of plant secondary metabolism in a way that will overcome such past difficulties by systematically analyzing the products produced in comparison to the genes activated under a variety of controlled conditions.

     The significance of such research is two-fold. First, the results will increase our understanding of the biosynthesis of medicinal metabolites in plants. We aim to gain knowledge of the mechanisms that regulate the metabolic flux within the pathways. Second, with cDNA libraries we perform subtractive hybridization analysis to identify enzymatic and regulatory genes. Subsequent analysis of plant and cell cultures at several time-points using microarray technology then tests to what extent each gene's expression differs under a variety of stimulatory and inhibitory conditions. After verification of the expression patterns, we will be able to show how gene expression is regulated by environmental and biotic stress treatments and identify critical enzymatic and regulatory genes that may have a role in specific biosynthesis.

     In addition, we are developing transformation systems for several important medicinal species, which will expedite further genetic enhancements once the genes for rate-limiting enzymes and their regulators are available. This is also connected with the elucidation of the relevant biochemical pathways. Thus, the primary objective of this research is directed toward unraveling the pathway intermediates and characterizing the principal genes responsible for the production and regulation of key medicinal compounds. Our long-term goal behind this research is to open the door to the use of controlled plant growth and the use of bioreactors for the production of natural products from plants through an understanding of how biotic and genetic factors can be manipulated to yield elevated levels of useful products. The techniques and knowledge established by this study can then be used for other plant systems and will likely generate an important source of medicinal compounds for the field of medicine.


Relevant Publications:

Natural Products from Plants. P.B. Kaufman, L.J. Cseke, S. Warber, J.A. Duke, and H.L. Brielmann: CRC Press. Boca Raton, Florida, (1999).

Cseke L.J., Dudareva N., and Pichersky E. (1998) Structure and Evolution of Linalool Synthase. Mol. Biol. Evol. 15(11):1491-1498.


Relevant Links:

National Center for Complementary and Alternative Medicine:

Natural Products from Plants:

Dr. Peter B. Kaufman: [1]    [2]

Dr. Debra Moriarity:

Dr. William Setzer:

Dr. Sanjay Swarup:

Dr. Bernhard Vogler: