Strict experimental evidence that apo-chaperonin GroEL does not accelerate protein folding, although it does accelerate one of its steps.
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چکیده
منابع مشابه
Reply to Marchenko et al.: Flux analysis of GroEL-assisted protein folding/unfolding.
Using NMR-based relaxation experiments, we showed that exchange between the folded state (F) of a metastable SH3 domain and a folding intermediate (I) is an order of magnitude faster when the SH3 domain is bound to apo GroEL than in free solution (1). We did not consider fluxes through the apo GroEL-assisted and unassisted pathways. Marchenko et al. (2) note that the approximate rate constants ...
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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...
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The cylindrical chaperonin GroEL and its lid-shaped cofactor GroES of Escherichia coli have an essential role in assisting protein folding by transiently encapsulating non-native substrate in an ATP-regulated mechanism. It remains controversial whether the chaperonin system functions solely as an infinite dilution chamber, preventing off-pathway aggregation, or actively enhances folding kinetic...
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Chaperonins are megadalton ring assemblies that mediate essential ATP-dependent assistance of protein folding to the native state in a variety of cellular compartments, including the mitochondrial matrix, the eukaryotic cytosol, and the bacterial cytoplasm. Structural studies of the bacterial chaperonin, GroEL, both alone and in complex with its co-chaperonin, GroES, have resolved the states of...
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 112 50 شماره
صفحات -
تاریخ انتشار 2015