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Branching in the sequential folding pathway of cytochrome c.

ABSTRACT: Previous results indicate that the folding pathways of cytochrome c and other proteins progressively build the target native protein in a predetermined stepwise manner by the sequential formation and association of native-like foldon units. The present work used native state hydrogen exchange methods to investigate a structural anomaly in cytochrome c results that suggested the concerted folding of two segments that have little structural relationship in the native protein. The results show that the two segments, an 18-residue omega loop and a 10-residue helix, are able to unfold and refold independently, which allows a branch point in the folding pathway. The pathway that emerges assembles native-like foldon units in a linear sequential manner when prior native-like structure can template a single subsequent foldon, and optional pathway branching is seen when prior structure is able to support the folding of two different foldons.

SUBMITTER: Krishna MM

PROVIDER: S-EPMC2206985 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Branching in the sequential folding pathway of cytochrome c.

Krishna Mallela M G MM Maity Haripada H Rumbley Jon N JN Englander S Walter SW

Protein science : a publication of the Protein Society 20070727 9

Previous results indicate that the folding pathways of cytochrome c and other proteins progressively build the target native protein in a predetermined stepwise manner by the sequential formation and association of native-like foldon units. The present work used native state hydrogen exchange methods to investigate a structural anomaly in cytochrome c results that suggested the concerted folding of two segments that have little structural relationship in the native protein. The results show that ...[more]

PMID: 17660254

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