The role of P450-mediated reactions in cellular processes has made the understanding of P450 mechanism a focus of intense research. The knowledge of catalytic mechanisms is an integral part of the elucidation o enzyme specificity, an important topic in areas as diverse as drug design, bioremediation, and cancer risk estimation. Whereas evidence generally supports alternate mechanistic pathways describing Cytochrome P450-mediated substrate oxidation, it is still unclear what really determines the rate of product formation and hence the pathway of oxidation. To address this issue, we propose to employ a model system consisting of human P450 1A2 and various anisole and N,N-dimethylaniline derivatives and to determine the catalytic steps comprising the demethylation of these substrates. The design of this system is intended to simplify the reactions of interest by minimizing the products of oxidation and to enable an analysis of the steps of the catalytic cycle employing a variety of techniques. As a complement to this work, site- directed mutagenesis will be carried out at key regions implicated in alternate oxidative pathways. The resulting mutants will be characterized and analyzed in terms of the appropriate model catalytic mechanisms.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32GM019808-02
Application #
6138315
Study Section
Physical Biochemistry Study Section (PB)
Program Officer
Ikeda, Richard A
Project Start
2000-01-01
Project End
Budget Start
2000-01-01
Budget End
2000-12-31
Support Year
2
Fiscal Year
2000
Total Cost
$37,516
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Biochemistry
Type
Schools of Medicine
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37212
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