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Viscosity Dependence of the Folding Rates of Proteins

D. K. Klimov·D. Thirumalai
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Abstract

The viscosity dependence of the folding rates for four sequences (the native state of three sequences is a beta-sheet, while the fourth forms an alpha-helix) is calculated for off-lattice models of proteins. Assuming that the dynamics is given by the Langevin equation we show that the folding rates increase linearly at low viscosities η, decrease as 1/ηat large ηand have a maximum at intermediate values. The Kramers theory of barrier crossing provides a quantitative fit of the numerical results. By mapping the simulation results to real proteins we estimate that for optimized sequences the time scale for forming a four turn α-helix topology is about 500 nanoseconds, whereas the time scale for forming a beta-sheet topology is about 10 microseconds.

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D. K. Klimov, D. Thirumalai. 1997-05-30. Viscosity Dependence of the Folding Rates of Proteins. https://doi.org/10.1103/physrevlett.79.317

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