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Jonathan S. Dordick’s research
is broadly in the areas of enzyme technology and biochemical
engineering, with much effort focused on designing enzymes
and enzyme systems to operate under harsh conditions, such
as those found in more conventional chemical processing. The
research strives to maintain the extraordinary selectivity
and reactivity that are the hallmark of enzymatic catalysis.
While conventional enzyme technology (i.e., catalysis in aqueous
solutions under ambient conditions) falls short of being able
to utilize biocatalysts under the extreme conditions typically
found in chemical processing, Dordick’s research is focused
on enhancing the capabilities of enzymes which can function
under unconventional conditions. This includes the application
of enzymes in organic solvents, under high pressures, at extremes
in temperatures, and at high ionic strengths.
“Specifically, in numerous projects,
we are investigating the structure and function of enzymes
in organic solvents to design biocatalysts with high stabilities
and activities in this unnatural environment,” Dordick
said.
Dordick’s work involves
the elucidation of kinetics, enzyme secondary and tertiary
structure, and dynamics in solvents with vastly different
physiochemical properties. Results over the past few years
have enabled him to prepare enzymes with extraordinarily high
activities and stabilities in nearly anhydrous systems. For
example, in collaboration with Douglas Clark at the University
of California, Berkeley, Dordick has found that simply lyophilizing
enzymes out of an aqueous salt solution results in enzyme
activities in hexane nearly as high as that in water. This
finding demonstrates that enzymes in organic solvents can
have native-like reactivity and shows that biocatalyst engineering
can be done simply and without extensive preparation. In another
example of biocatalyst engineering, Dordick has discovered
that enzymes can be dissolved in organic solvents through
the use of surfactant ion pairing. As with the salt-activated
preparations, the ion-paired organic solvent-soluble preparations
show reactivity in solvents nearly as high as in water. This
approach has led to the development of enzyme-polymer composites,
wherein enzymes are incorporated into polymer matrices that
comprise common plastics, paints, and coatings. Such “biocatalytic
plastics” have found application as highly active and
stable catalysts for biotransformations, as antifouling paints
and coatings, and as highly selective adsorbents for affinity
chromatography. Finally, in combination with biocatalyst engineering,
Dordick is exploring the use of protein engineering and directed
molecular evolution to design new selectivities and activities
from common enzymes used in biotransformations.
In addition to enzyme engineering, other research programs
led by Dordick include the use of enzymes as catalysts for
polymer synthesis. In particular, they have prepared novel
sugar-based materials for use as water absorbents, drug delivery
matrices, and enzyme immobilization supports. In a related
area, enzymes from agricultural sources have been identified
as potentially useful biocatalysts. Finally, together with
Douglas Clark and scientists from Iowa-based EnzyMed, Inc.,
Dordick is using enzymes synthetically in a technology known
as “combinatorial biocatalysis.”
 Jonathan
S. Dordick
Department Head and Professor, Department of Chemical Engineering
Rensselaer Polytechnic Institute
110 8th Street
Troy, NY 12180-3590
(518) 276-2899
dordick@rpi.edu
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