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Probing the cytochrome c' folding landscape.

ABSTRACT: The folding kinetics of R. palustris cytochrome c' (cyt c') have been monitored by heme absorption and native Trp72 fluorescence at pH 5. The Trp72 fluorescence burst signal suggests early compaction of the polypeptide ensemble. Analysis of heme transient absorption spectra reveals deviations from two-state behavior, including a prominent slow phase that is accelerated by the prolyl isomerase cyclophilin. A nonnative proline configuration (Pro21) likely interferes with the formation of the helical bundle surrounding the heme.

SUBMITTER: Pletneva EV

PROVIDER: S-EPMC2110879 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

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Probing the cytochrome c' folding landscape.

Pletneva Ekaterina V EV Zhao Ziqing Z Kimura Tetsunari T Petrova Krastina V KV Gray Harry B HB Winkler Jay R JR

Journal of inorganic biochemistry 20070621 11-12

The folding kinetics of R. palustris cytochrome c' (cyt c') have been monitored by heme absorption and native Trp72 fluorescence at pH 5. The Trp72 fluorescence burst signal suggests early compaction of the polypeptide ensemble. Analysis of heme transient absorption spectra reveals deviations from two-state behavior, including a prominent slow phase that is accelerated by the prolyl isomerase cyclophilin. A nonnative proline configuration (Pro21) likely interferes with the formation of the helic ...[more]

PMID: 17673297

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