A Role for Confined Water in Chaperonin Function

James H. Clark Center, S297, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society (Impact Factor: 11.44). 10/2008; 130(36):11838-9. DOI: 10.1021/ja802248m
Source: PubMed

ABSTRACT Chaperonins engulf other proteins and accelerate their folding by an unknown mechanism. Here, we combine all-atom molecular dynamics simulations with data from experimental assays of the activity of the bacterial chaperonin GroEL to demonstrate that a chaperonin's ability to facilitate folding is correlated with the affinity of its interior surface for water. Our results suggest a novel view of the behavior of confined water for models of in vivo protein folding scenarios.

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