Snapshots of cytochrome c folding.
Dansyl-to-heme distance distributions [P(r)] during folding have been determined in five variants of Saccharomyces cerevisiae iso-1 ferricytochrome c (labeled at mutant Cys residues 4, 39, 50, 66, and 99) by analysis of fluorescence energy-transfer kinetics. Moment analysis of the P(r) distributions clearly indicates that cytochrome c refolding is not a simple two-state process. After 1 ms of folding, the polypeptide ensemble is not uniformly collapsed and there are site variations in the relative populations of collapsed structures. P(r) distributions reveal structural features of the multiple intermediate species and evolution of the polypeptide ensemble.
Pletneva
Ekaterina V
EV
Beckman Institute, California Institute of Technology, Pasadena, CA 91125, USA.
Gray
Harry B
HB
Winkler
Jay R
JR
D045304:Cytochromes c / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D031541:Fluorescence Resonance Energy Transfer; D006418:Heme / Q000378:metabolism; D007700:Kinetics; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics
D010455:Peptides; D006418:Heme; D045304:Cytochromes c