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arXiv · 0710.5533

Peptide Folding Kinetics from Replica Exchange Molecular Dynamics

Nicolae-Viorel Buchete·Gerhard Hummer
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Abstract

We show how accurate kinetic information, such as the rates of protein folding and unfolding, can be extracted from replica-exchange molecular dynamics (REMD) simulations. From the brief and continuous trajectory segments between replica exchanges, we estimate short-time propagators in conformation space and use them to construct a master equation. For a helical peptide in explicit water, we determine the rates of transitions both locally between microscopic conformational states and globally for folding and unfolding. We show that accurate rates in the ~1/(100 ns) to ~1/(1 ns) range can be obtained from REMD with exchange times of 5 ps, in excellent agreement with results from long equilibrium molecular dynamics.

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Nicolae-Viorel Buchete, Gerhard Hummer. 2008-02-11. Peptide Folding Kinetics from Replica Exchange Molecular Dynamics. https://doi.org/10.1103/physreve.77.030902

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