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arXiv · 1804.04099

Kinetic signature of cooperativity in the irreversible collapse of a polymer

Vittore F. Scolari·Guillaume Mercy·Romain Koszul·Annick Lesne·Julien Mozziconacci
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Abstract

We investigate the kinetics of a polymer collapse due to the formation of irreversible crosslinks between its monomers. Using the contact probability $P(s)$ as a scale-dependent order parameter depending on the chemical distance $s$, our simulations show the emergence of a cooperative pearling instability. Namely, the polymer undergoes a sharp conformational transition to a set of absorbing states characterized by a length scale $\xi$ corresponding to the mean pearl size. This length and the transition time depend on the polymer equilibrium dynamics and the crosslinking rate. We confirm experimentally this transition using a DNA conformation capture experiment in yeast.

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Vittore F. Scolari, Guillaume Mercy, Romain Koszul, Annick Lesne, Julien Mozziconacci. 2018-04-11. Kinetic signature of cooperativity in the irreversible collapse of a polymer. https://doi.org/10.1103/physrevlett.121.057801

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