Using the results from our previous work on yeast cytochrome c peroxidase (CcP) complexes, this proposal reflects the comments of the previous NIH Study Section which recommended a proposal tightly focused on NMR studies of noncovalent CcP/cytochrome c complexes. In this proposal we intend to focus on comparative studies of a nonphysiological type of CcP complex: between CcP and horse cytochrome c; and a physiological type of CcP complex: between CcP and its natural redox partner yeast iso- 1 cytochrome c. This discrimination of complex type is based upon results from our work during the past three years, which segregate themselves along species-specific lines. One of our most interesting results during this time has been the resolution of free and bound ferricytochrome c resonances in NMR spectra of CcP/ferricytochrome c noncovalent complexes. We propose to further characterize these complexes by NMR spectroscopy, elucidate the complex dissociation rate constants and determine the effects on cytochrome c NMR spectra of forming complexes with native, wild-type CcP (a ferric, high-spin heme protein), and as well, with the oxidized intermediates, CcP-I (compound-I) and CcP-II (compound-II), and cyanide-inhibited CcP (CcPCN). NMR detection of effects of complex formation upon CcP will be attempted using CcPCN in combination with ferro- and ferricytochromes c.
| Yi, Q; Erman, J E; Satterlee, J D (1994) Studies of protein-protein association between yeast cytochrome c peroxidase and yeast iso-1 ferricytochrome c by hydrogen-deuterium exchange labeling and proton NMR spectroscopy. Biochemistry 33:12032-41 |
| Moench, S J; Erman, J E; Satterlee, J D (1993) Species-specific differences in covalently crosslinked complexes of yeast cytochrome c peroxidase with horse and yeast iso-1 ferricytochromes c. Int J Biochem 25:1335-42 |
| Yi, Q; Erman, J E; Satterlee, J D (1993) Proton NMR studies of noncovalent complexes of cytochrome c peroxidase-cyanide with horse and yeast ferricytochromes c. Biochemistry 32:10988-94 |
