The overall objective is to determine how the structure and dynamics of low molecular weight cytochromes relate to their function as electron transport catalysts. Cytochromes are ubiquitous electron transport proteins found in all cell lines. An understanding of their function will provide fundamental knowledge into a central process of energy metabolism. The main technique will be NMR spectroscopy with accent on two dimensional solution studies. The primary experimental systems are cytochromes c551 from Pseudomonas aeruginosa and Pseudomonas stutzeri.
The specific aims are to (a) assign their proton spectra in the oxidized and reduced forms, (b) compare their structures to each other and to larger eukaryotic cytochromes, (c) determine the kinetics of amide NH exchange as a probe for internal flexibility, and, (d) assess the importance of non-amino acid elements in determining the final tertiary conformation.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM043292-02
Application #
3302338
Study Section
Biophysical Chemistry Study Section (BBCB)
Project Start
1991-05-01
Project End
1995-04-30
Budget Start
1992-05-01
Budget End
1993-04-30
Support Year
2
Fiscal Year
1992
Total Cost
Indirect Cost
Name
University of Alabama in Tuscaloosa
Department
Type
Schools of Arts and Sciences
DUNS #
City
Tuscaloosa
State
AL
Country
United States
Zip Code
35487
Matthews, J C; Timkovich, R; Liu, M Y et al. (1995) Siroamide: a prosthetic group isolated from sulfite reductases in the genus Desulfovibrio. Biochemistry 34:5248-51
Palmedo, G; Seither, P; Korner, H et al. (1995) Resolution of the nirD locus for heme d1 synthesis of cytochrome cd1 (respiratory nitrite reductase) from Pseudomonas stutzeri. Eur J Biochem 232:737-46
Cai, M; Timkovich, R (1994) Solution conformation of cytochrome c-551 from Pseudomonas stutzeri ZoBell determined by NMR. Biophys J 67:1207-15
Timkovich, R; Cai, M; Zhang, B et al. (1994) Characteristics of the paramagnetic 1H-NMR spectra of the ferricytochrome c-551 family. Eur J Biochem 226:159-68
Timkovich, R; Cai, M (1993) Investigation of the structure of oxidized Pseudomonas aeruginosa cytochrome c-551 by NMR: comparison of observed paramagnetic shifts and calculated pseudocontact shifts. Biochemistry 32:11516-23
Arciero, D M; Hooper, A B; Cai, M et al. (1993) Evidence for the structure of the active site heme P460 in hydroxylamine oxidoreductase of Nitrosomonas. Biochemistry 32:9370-8
Cai, M; Timkovich, R (1992) Ionization of the heme propionate substituents in pseudomonad cytochromes c-551. FEBS Lett 311:213-6
Timkovich, R; Walker 2nd, L A; Cai, M (1992) Hydrogen exchange in Pseudomonas cytochrome c-551. Biochim Biophys Acta 1121:8-15
Cai, M; Bradford, E G; Timkovich, R (1992) Investigation of the solution conformation of cytochrome c-551 from Pseudomonas stutzeri. Biochemistry 31:8603-12
Cai, M L; Timkovich, R (1991) Proton resonance assignments for Pseudomonas aeruginosa ferrocytochrome c-551. Biochem Biophys Res Commun 178:309-14