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Three-body Interactions Improve the Prediction of Rate and Mechanism in Protein Folding Models

M. R. Ejtehadi·S. P. Avall·S. S. Plotkin
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Abstract

Here we study the effects of many-body interactions on rate and mechanism in protein folding, using the results of molecular dynamics simulations on numerous coarse-grained C-alpha-model single-domain proteins. After adding three-body interactions explicitly as a perturbation to a Go-like Hamiltonian with native pair-wise interactions only, we have found 1) a significantly increased correlation with experimental phi-values and folding rates, 2) a stronger correlation of folding rate with contact order, matching the experimental range in rates when the fraction of three-body energy in the native state is ~ 20%, and 3) a considerably larger amount of 3-body energy present in Chymotripsin inhibitor than other proteins studied.

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M. R. Ejtehadi, S. P. Avall, S. S. Plotkin. 2004-07-14. Three-body Interactions Improve the Prediction of Rate and Mechanism in Protein Folding Models. https://doi.org/10.1073/pnas.0403486101

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