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Stretching of proteins in a force-clamp

Piotr Szymczak·Marek Cieplak
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Abstract

Mechanically induced protein unfolding in the force-clamp apparatus is shown, in a coarse-grained model of ubiquitin, to have lognormal statistics above a treshold force and exponential below it. Correspondingly, the mean unfolding time is slowly varying and exponentially decreases as a function of the force. The time dependencies of the end-to-end distances are also distinct. The time sequence of unfolding events weakly depends on force and much of it resembles that for stretching at constant speed. A more complicated time dependence arises for integrin.

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Piotr Szymczak, Marek Cieplak. 2005-12-01. Stretching of proteins in a force-clamp. https://arxiv.org/abs/q-bio/0512004

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