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Quantifying Nonnative Interactions in the Protein-Folding Free-Energy Landscape.

ABSTRACT: Protein folding is a central problem in biological physics. Energetic roughness is an important aspect that controls protein-folding stability and kinetics. The roughness is associated with conflicting interactions in the protein and is also known as frustration. Recent studies indicate that an addition of a small amount of energetic frustration may enhance folding speed for certain proteins. In this study, we have investigated the conditions under which frustration increases the folding rate. We used a C? structure-based model to simulate a group of proteins. We found that the free-energy barrier at the transition state (?F) correlates with nonnative-contact variation (?A), and the simulated proteins are clustered according to their fold motifs. These findings are corroborated by the Clementi-Plotkin analytical model. As a consequence, the optimum frustration regime for protein folding can be predicted analytically.

SUBMITTER: Mouro PR

PROVIDER: S-EPMC4968343 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Quantifying Nonnative Interactions in the Protein-Folding Free-Energy Landscape.

Mouro Paulo Ricardo PR de Godoi Contessoto Vinícius V Chahine Jorge J Junio de Oliveira Ronaldo R Pereira Leite Vitor Barbanti VB

Biophysical journal 20160701 2

Protein folding is a central problem in biological physics. Energetic roughness is an important aspect that controls protein-folding stability and kinetics. The roughness is associated with conflicting interactions in the protein and is also known as frustration. Recent studies indicate that an addition of a small amount of energetic frustration may enhance folding speed for certain proteins. In this study, we have investigated the conditions under which frustration increases the folding rate. W ...[more]

PMID: 27463131

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