Seminar Announcement

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Seminar Announcement
Dr. Joe Chappell Professor, Plant and Soil
Sciences Plant Biology Program University of
Kentucky, Lexington, KY
Unraveling the Catalytic Specificity of Terpene
Biosynthetic Enzymes and Engineering the
Biosynthesis of Novel Terpenes in Yeast and
Plants 400, Wednesday, December 5, 2007
ASU Biosciences Institute Room 107 Supported
by NSF EPSCoR Host Dr. Pam Weathers (4795)
Abstract Many plants respond to pathogen attack
by the synthesis and secretion of anti-microbial
compounds. For example, solanaceous plants
produce anti-microbial terpenes that inhibit
germination and growth of several fungal species.
The production of these chemicals has been
interpreted as an important defense response. We
have also hypothesized that an understanding of
the mechanisms responsible for the biosynthesis
of the anti-microbial terpenes should provide a
means for engineering the generation of novel and
more efficacious compounds. Towards that goal, we
have elucidated a 2-step biosynthetic pathway for
capsidiol, an anti-microbial sesquiterpene
di-alcohol. The pathway consists of a synthase
that catalyzes the cyclization of farnesyl
diphosphate to a bi-cyclic hydrocarbon structure,
followed by the action of a P450 hydroxylase that
introduces hydroxyl functions with stereo- and
regio- specificity. Using several different
approaches, we have mapped functional features of
the respective enzymes, and have used this
information to evolve novel catalytic activities
for the generation of unique chemical entities -
biologically active chemicals and chemicals of
industrial interest. For more visit
http//www.uky.edu/Ag/Agronomy/Chappell/welcome.ht
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