The Guengerich laboratory is interested in the enzymes involved in the activation and processing of xenobiotic chemicals (i.e., those not normally found in the body, such as drugs and carcinogens).
RESEARCH INTERESTS
Mechanisms of Oxidation of Drugs & Carcinogens Catalyzed by Human P450s
(NIH R37 CA90426) involves the cytochrome P450 (P450) enzymes. Work involves the use of site-directed and random mutagenesis and the heterologous expression of human P450 enzymes in bacteria. The P450 enzymes are purified and used in experiments directed at understanding details of catalysis. The work involves chemical synthesis and analysis, spectroscopy, and kinetics. A new focus is on understanding the function of the human "orphan" P450s.
Catalytic Functions of Streptomyces P450s
(NIH R01 GM69970, with Prof M. R. Waterman) is a project dealing with characterization of the P450s in Streptomyces. Our role in the project involves characterization of the interaction of these (18) P450s with various redox partners, the identification of P450 substrates and reaction products, and eventually the mutagenesis of the P450s to synthesize new drugs, esp. antibiotics.
Bioactivation of Halogenated Hydrocarbons & Bifunctional Electrophiles
(NIH R01 ES10546) involves how activated carcinogens react with proteins and DNA. The focus is on a series of halogenated hydrocarbons (trihaloethylenes, ethylene dibromide, and methylene halides)
and other bifunctional electrophiles, e. g. butadiene diepoxide. Some of these chemicals are activated by conjugation with the tripeptide glutathione (GSH) by GSH transferases or a DNA repair protein
(O6-alkylguanine transferase). Bacterial genotoxicity systems are utilized, as well as many chemical and spectroscopic approaches.Polymerase Interactions with Carcinogen-Modified DNA
(NIH R01 ES10375) involves how polymerases interact with carcinogen-modified DNA to produce base-pair and frameshift mutations. The work focuses on the use of site-specifically modified oligonucleotides (modified with carcinogens) and polymerase enzymology, including prokaryotic models and some mammalian polymerases and involves pre-steady-state and steady-state kinetic analysis of the polymerase reaction cycle, plus the use of X-ray crystallography in defining the relationships of structure and function.
LABORATORY PERSONNEL
Professor Guengerich
Karen Angel (Research Asst.)
Dr. Jeffrey Beckman (Research Fellow)
Dr. Qian Cheng (Research Fellow)
Dr. Goutam Chowdhury (Research Fellow)
Dr. Robert Eoff (Research Fellow)
Elisabeth Loecken (Graduate Student)
Dr. Martha Martin (Research Asst.)
Louisa Morrison (Graduate Student)
Dr. Giovanna Salamanca-Pinzón (Research Fellow)
Christal Sohl (Graduate Student)
Dr. Zhong-mei Tang (Research Fellow)
Dr. Huidong Zhang (Research Fellow)
General References and Recent Representative Articles