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Snapshots of cytochrome c folding.

ABSTRACT: 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.

SUBMITTER: Pletneva EV

PROVIDER: S-EPMC1317956 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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Snapshots of cytochrome c folding.

Pletneva Ekaterina V EV Gray Harry B HB Winkler Jay R JR

Proceedings of the National Academy of Sciences of the United States of America 20051212 51

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 relati ...[more]

PMID: 16344477

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