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A possible mechanism for cold denaturation of proteins at high pressure

Manuel I. Marques·Jose M. Borreguero·H. Eugene Stanley·Nikolay V. Dokholyan
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Abstract

We study cold denaturation of proteins at high pressures. Using multicanonical Monte Carlo simulations of a model protein in a water bath, we investigate the effect of water density fluctuations on protein stability. We find that above the pressure where water freezes to the dense ice phase ($\approx2$ kbar), the mechanism for cold denaturation with decreasing temperature is the loss of local low-density water structure. We find our results in agreement with data of bovine pancreatic ribonuclease A.

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Manuel I. Marques, Jose M. Borreguero, H. Eugene Stanley, Nikolay V. Dokholyan. 2003-06-11. A possible mechanism for cold denaturation of proteins at high pressure. https://doi.org/10.1103/physrevlett.91.138103

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