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Enhanced sampling and applications in protein folding in explicit solvent.

ABSTRACT: We report a single-copy tempering method for simulating large complex systems. In a generalized ensemble, the method uses runtime estimate of the thermal average energy computed from a novel integral identity to guide a continuous temperature-space random walk. We first validated the method in a two-dimensional Ising model and a Lennard-Jones liquid system. It was then applied to folding of three small proteins, trpzip2, trp-cage, and villin headpiece in explicit solvent. Within 0.5-1 microsecond, all three systems were reversibly folded into atomic accuracy: the alpha carbon root mean square deviations of the best folded conformations from the native states were 0.2, 0.4, and 0.4 A, for trpzip2, trp-cage, and villin headpiece, respectively.

SUBMITTER: Zhang C

PROVIDER: S-EPMC2905458 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Enhanced sampling and applications in protein folding in explicit solvent.

Zhang Cheng C Ma Jianpeng J

The Journal of chemical physics 20100601 24

We report a single-copy tempering method for simulating large complex systems. In a generalized ensemble, the method uses runtime estimate of the thermal average energy computed from a novel integral identity to guide a continuous temperature-space random walk. We first validated the method in a two-dimensional Ising model and a Lennard-Jones liquid system. It was then applied to folding of three small proteins, trpzip2, trp-cage, and villin headpiece in explicit solvent. Within 0.5-1 microsecon ...[more]

PMID: 20590175

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