In the broadest sense, our research objectives are to understand biological processes and phenomena in terms of physical mechanisms and to explore the adaptation of physical phenomena and techniques to problems in biology. The more specific goals and problems to which we are addressing ourselves in this proposal are the following: 1. The mechanisms of energy conversion and electron transfer in a protein-chlorophyll complex solubilized from a bacterial membrane and the characterization of the protein complex. Different physical techniques (e.g., EPR, optical techniques, electron microscopy, Mossbauer spectroscopy, etc.) and biochemical methods (e.g., immunological, amino acid composition and sequence determination, gel filtration, gel electrophoresis, etc.) are being used. 2. The application of the technique of fluctuation spectroscopy to biology. In this technique the fluctuations (noise) are used to obtain information about the kinetic parameters of a system (i.e., rate constants) or from the number fluctuations, molecular weights of macromolecules (e.g., DNA) can be determined. 3. The use of coherent light scattering to study aggregation processes of macromolecules with special emphasis on the investigation of crystallization mechanisms of proteins.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM013191-21
Application #
3268436
Study Section
Biophysics and Biophysical Chemistry A Study Section (BBCA)
Project Start
1976-05-10
Project End
1986-06-30
Budget Start
1985-07-01
Budget End
1986-06-30
Support Year
21
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of California San Diego
Department
Type
Schools of Arts and Sciences
DUNS #
077758407
City
La Jolla
State
CA
Country
United States
Zip Code
92093
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Durbin, S D; Feher, G (1990) Studies of crystal growth mechanisms of proteins by electron microscopy. J Mol Biol 212:763-74
Calvo, R; Passeggi, M C; Isaacson, R A et al. (1990) Electron paramagnetic resonance investigation of photosynthetic reaction centers from Rhodobacter sphaeroides R-26 in which Fe2+ was replaced by Cu2+. Determination of hyperfine interactions and exchange and dipole-dipole interactions between Cu2+ and QA- Biophys J 58:149-65
Lubitz, W; Isaacson, R A; Okamura, M Y et al. (1989) ENDOR studies of the intermediate electron acceptor radical anion I-. in Photosystem II reaction centers. Biochim Biophys Acta 977:227-32
Allen, J P (1988) Crystallization and preliminary X-ray diffraction analysis of cytochrome c2 from Rhodobacter sphaeroides. J Mol Biol 204:495-6

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