Abstract

The proposed research involves fluorescence studies of drug-DNA adducts and proteins. The complicated emissions from these systems will be resolved by global analysis of time-resolved fluorescence decay data obtained under different experimental conditions. The interaction of pyrrolo(1,4)- bensodiazepine antitumor antibiotics with DNA will be characterized using spectroscopic and hydrodynamic techniques. The effects of DNA sequence and conformation on the covalent drug-DNA interaction will be investigated in fluorescence and CD experiments with synthetic and natural DNAs. The effects of drug binding on DNA solution conformation will be determined by static and dynamic light scattering. These antibiotics provide a new fluorescent probe for rapid internal motions in the DNA double helix. DNA dynamics will be studied by fluorescence depolarization measurements in the time as well as frequency domains. The emission anisostropy data for covalent drug-DNA adducts will be analyzed according to the predicted nonexponential decay law. The effects on the dynamics of factors influencing DNA structure will be examined. Two enzymes involved in nucleic acid metabolism will be investigated by steady-state and time-resolved fluorescence measurements. The interactions of terminal transferase with monomer and polymer substrates and of adenosine deaminase with ground-state and transition-state inhibitors will be characterized. The effects of ligand binding on protein conformation nand dynamics will be determined. The above research is aimed at elucidation of the role of DNA flexibility in biological function. It also offers insight into the mechanism of action of antitumor antibiotics and of enzymes important in human leukemia.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM035009-02A1
Application #
3287055
Study Section
Biophysics and Biophysical Chemistry B Study Section (BBCB)
Project Start
1984-09-01
Project End
1991-08-31
Budget Start
1986-09-01
Budget End
1987-08-31
Support Year
2
Fiscal Year
1986
Total Cost
Indirect Cost

  Institution

Name
Louisiana State University A&M Col Baton Rouge
Department
Type
Schools of Arts and Sciences
DUNS #
075050765
City
Baton Rouge
State
LA
Country
United States
Zip Code
70803

  Publications

Watrob, H; Liu, W; Chen, Y et al. (2001) Solution conformation of EcoRI restriction endonuclease changes upon binding of cognate DNA and Mg2+ cofactor. Biochemistry 40:683-92
Liu, W; Chen, Y; Watrob, H et al. (1998) N-termini of EcoRI restriction endonuclease dimer are in close proximity on the protein surface. Biochemistry 37:15457-65
Barkley, M D; Chen, Q; Walczak, W J et al. (1996) Time-resolved fluorescence studies of tomaymycin bonding to synthetic DNAs. Biophys J 70:1923-32
Chen, Q; Chowdhury, F N; Maskos, K et al. (1994) Time-resolved fluorescence studies of tomaymycin bonding to DNA. Biochemistry 33:8719-27
Kim, S J; Chowdhury, F N; Stryjewski, W et al. (1993) Time-resolved fluorescence of the single tryptophan of Bacillus stearothermophilus phosphofructokinase. Biophys J 65:215-26
Barkley, M D; Thomas, T J; Maskos, K et al. (1991) Steady-state fluorescence and molecular-modeling studies of tomaymycin-DNA adducts. Biochemistry 30:4421-31
Zhu, B C; Laine, R A; Barkley, M D (1990) Intrinsic tryptophan fluorescence measurements suggest that polylactosaminyl glycosylation affects the protein conformation of the gelatin-binding domain from human placental fibronectin. Eur J Biochem 189:509-16
Boyd, F L; Stewart, D; Remers, W A et al. (1990) Characterization of a unique tomaymycin-d(CICGAATTCICG)2 adduct containing two drug molecules per duplex by NMR, fluorescence, and molecular modeling studies. Biochemistry 29:2387-403
Philips, A V; Coleman, M S; Maskos, K et al. (1989) Time-resolved fluorescence spectroscopy of human adenosine deaminase: effects of enzyme inhibitors on protein conformation. Biochemistry 28:2040-50
Philips, A V; Robbins, D J; Coleman, M S et al. (1987) Immunoaffinity purification and fluorescence studies of human adenosine deaminase. Biochemistry 26:2893-903

Showing the most recent 10 out of 11 publications