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Critical nucleation size in the folding of small apparently two-state proteins.

ABSTRACT: For apparently two-state proteins, we found that the size (number of folded residues) of a transition state is mostly encoded by the topology, defined by total contact distance (TCD) of the native state, and correlates with its folding rate. This is demonstrated by using a simple procedure to reduce the native structures of the 41 two-state proteins with native TCD as a constraint, and is further supported by analyzing the results of eight proteins from protein engineering studies. These results support the hypothesis that the major rate-limiting process in the folding of small apparently two-state proteins is the search for a critical number of residues with the topology close to that of the native state.

SUBMITTER: Bai Y

PROVIDER: S-EPMC2286761 | biostudies-literature | 2004 May

REPOSITORIES: biostudies-literature

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Critical nucleation size in the folding of small apparently two-state proteins.

Bai Yawen Y Zhou Hongyi H Zhou Yaoqi Y

Protein science : a publication of the Protein Society 20040409 5

For apparently two-state proteins, we found that the size (number of folded residues) of a transition state is mostly encoded by the topology, defined by total contact distance (TCD) of the native state, and correlates with its folding rate. This is demonstrated by using a simple procedure to reduce the native structures of the 41 two-state proteins with native TCD as a constraint, and is further supported by analyzing the results of eight proteins from protein engineering studies. These results ...[more]

PMID: 15075405

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