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Helicase on DNA: A Phase coexistence based mechanism

Somendra M. Bhattacharjee·Flavio Seno
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Abstract

We propose a phase coexistence based mechanism for activity of helicases, ubiquitous enzymes that unwind double stranded DNA. The helicase-DNA complex constitutes a fixed-stretch ensemble that entails a coexistence of domains of zipped and unzipped phases of DNA, separated by a domain wall. The motor action of the helicase leads to a change in the position of the fixed constraint thereby shifting the domain wall on dsDNA. We associate this off-equilibrium domain wall motion with the unzipping activity of helicase. We show that this proposal gives a clear and consistent explanation of the main observed features of helicases.

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Somendra M. Bhattacharjee, Flavio Seno. 2003-03-24. Helicase on DNA: A Phase coexistence based mechanism. https://doi.org/10.1088/0305-4470%2F36%2F13%2F102

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