rfcolman@udel.edu |
Chemistry Home Page |
University of Delaware |
Area of Research Biochemistry. Structure, function, and mechanism of action of isocitrate dehydrogenases, glutamate dehydrogenases, glutathione S-transferases; affinity labeling and site-directed mutagenesis of nucleotide sites in enzymes.
Ph.D., 1962, Radcliffe Graduate School, Harvard University, Advisor: F. H. Westheimer, Chemistry Department (Biochemistry)
Postdoctoral Fellow, 1962-64, National Institutes of Health, Bethesda, MD (Herbert Tabor and Simon Black, laboratory and section chiefs - Biochemistry)
Postdoctoral Fellow 1964-66, Washington University School of Medicine, St. Louis, MO (Carl Frieden, sponsor - Biochemistry)
Willis F. Harrington Professor, Dept. of Chemistry and Biochemistry, U. of Delaware, 2002-date.
Director, Training and Mentoring Core of the NIH-funded Biomedical Research Infrastructure Network of Delaware (BRIN Program), 2001-2004.
Program Director, NIH-funded Chemistry-Biology Interface Graduate Program, U. of Delaware, 1993-date.
Professor, Dept. of Chemistry and Biochemistry, U. of Delaware, 1973-2002.
Associate Professor, Dept. of Biological Chemistry, Harvard Medical School, 1972-73.
Assistant Professor, Dept. of Biological Chemistry, Harvard Medical School, 1969-72.
Tutor in Biochemical Sciences, Harvard College, 1967-73.
Associate, Dept. of Biological Chemistry, Harvard Medical School, 1967-69.
Assistant Professor, Dept. of Biological Chemistry, Washington University
School of Medicine, 1966-67.
SCIENTIFIC SOCIETIES--American Society for Biochemistry and Molecular Biology; American Chemical Society; American Association for Advancement of Science; New York Academy of Sciences; Biophysical Society; The Protein Society.
SERVICE TO SCIENTIFIC JOURNALS
Editorial Board, The Journal of Biological Chemistry, 1982-1987.
Executive Editor, Enzyme Mechanisms and Metabolism Section, Archives of Biochemistry and Biophysics, 1984-2001.
Editorial Board, Archives of Biochemistry and Biophysics, 1979-84, 2001-2004.
Associate Editor, The Journal of Protein Chemistry, 1981-87.
Task Force of American Chemical Society to review the journal Biochemistry, 1985-86.
Editorial Board, Protein Expression and Purification, 1990-date.
Editorial Advisory Committee, Protein Science, 1991-1996.
Task Force of American Chemical Society to review C&E News, 1993.
GRANT REVIEW COMMITTEES
Ad hoc member of NIH Special Emphasis Panel to review applications for predoctoral fellowships for minority students and students with disabilities, 2003, 2004.
Member of NSF Review Panel, Molecular Biochemistry Program, 1996-2003.
N.I.H. Chemistry/Biology Interface Predoctoral Training Programs Special Review Committee, 1994, 1995.
Ad hoc member of NIH Study Section to review Small Business Innovation Research Grants (SBIR), 1994; of NIH Medical Biochemistry Study Section, 1997.
N.I.H. Physical Biochemistry Study Section, 1989-1992.
American Cancer Society, Biochemistry and Carcinogenesis Study Section, 1986-1990. Chairman, 1989-90.
Ad hoc reviewer of Biotechnology training grants and postdoctoral fellowships.
American Heart Association: Physiological Chemistry B Study Section, 1985-1988.
National Institute of General Medical Sciences, Cellular and Molecular Basis of Disease Review Committee (Training Grants), 1979-1983.
N.I.H. Biochemistry Study Section, 1974-1978.
Research Committee, Delaware Cancer Network, 1978-1985.
Research Committee, Delaware Heart Association, 1978-81.
SERVICE TO PROFESSIONAL SOCIETIES
Past Chair, Division of Biological Chemistry, American Chemical Society, 2000-2002.
Chair, Division of Biological Chemistry, American Chemical Society, 1998-2000.
Member, U.S. National Committee for the International Union of Biochemistry and Molecular Biology, 2000-2003.
External Advisory Committee member to South Carolina BRIN Program, 2002.
Chair Elect, Division of Biological Chemistry, American Chemical Society, 1996-1998.
Council Member, Am. Soc. Biochem. and Molecular Biology, 1993-1996.
Member, Publications Committee, Am. Soc. of Biochem. and Molecular Biology, 1988-91.
Councilor, Division of Biological Chemistry, American Chemical Society.
Chair, Awards Committee of the Protein Society, 1990.
Chairman, Nominating Committee, ASBMB, 1987-88.
Treasurer, American Soc. of Biological Chemists, 1981-85.
Executive Committee, Div. of Biological Chemistry, American Chemical Society, 1984-1990.
Nominating Committee, American Society of Biol. Chemists, 1976-77.
Nominating Committee, Div. of Biol. Chemistry, American Chemical Society, 1974-76; 1978-79.
Committee on Educational Affairs, Am. Soc. of Biological Chemists, 1976-78.
Committee on Women in Biochemistry, Am. Soc. of Biochemistry and Molecular
Biology, 1972-74, 1987-1991.
Dr. Colman’s laboratory seeks to understand the catalytic activity of enzymes in terms of protein structure. Being studied currently are glutathione S-transferases, adenylosuccinate lyases and isocitrate dehydrogenases.
The dimeric glutathione S-transferases (GST) are important in the detoxification of xenobiotics (or foreign chemicals) catalyzing the nucleophilic attack by the thiol of glutathione on the xenobiotic substrates. The elevation of GST levels in solid tumors is a major factor in the development of resistance to treatment of cancer patients with cytotoxic agents. Using the approach of affinity labeling, Dr. Colman’s lab probes the active sites of the enzymes. Novel reagents are synthesized, based on the structure of glutathione or on that of xenobiotic substrates, which feature reactive groups capable of covalently labeling amino acid side chains after the reagent binds at the active site. Her lab has recently begun studying an entirely new function for glutathione S–transferases: the ability to form complexes with other enzymes and alter their activities; examples are 1–cysteine peroxiredoxin, and cell signaling protein kinases.
Dr. Colman’s lab is also examining adenylosuccinate lyase (ASL), which catalyzes a key step in purine biosynthesis: the conversion of adenylosuccinate to AMP + fumarate. The importance of ASL’s metabolic role is indicated by the severity of the symptoms of ASL deficiency in humans; the disease is associated with mental retardation, and autism. The overall goal is to understand the chemical and structural contributions to catalysis by normal tetrameric ASL and the molecular basis for decreased activity in patients with ASL deficiency. Dr. Colman’s lab has identified by affinity labeling and site–directed mutagenesis, many of the amino acids critical for catalysis in the bacterial ASL. The lab has recently purified recombinant human ASL and is now examining the effect on the enzyme’s structure, stability and catalytic activity of the mutations resposible for human ASL deficiency disease
Finally, Dr. Colman’s laboratory studies two distinct mammalian heart isocitrate dehydrogenases (IDH), one NADP-dependent and not regulated, and the other NAD-specific and activated by ADP. IDH catalyzes a rate limiting step in the energy-producing Citric Acid Cycle. In heart failure, decreases in the NAD enzyme are associated with decreased oxidative metabolism and energy production. In contrast, the NADP-specific IDHs have a major role in the generation of NADPH for reductive biosynthesis and protection against oxidative stress in the heart. Dr. Colman’s lab is now focusing on the human NAD-specific enzyme which has 3 types of subunits, present in the ratio 2α:1ß:1γ. The roles of the dissimilar subunits of the NAD enzyme are being evaluated by identification of the subunit types affected by site-specific labels, and of the function(s) altered upon replacement of a key amino acid in one type of enzyme subunit.