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arXiv · 2302.11402

Cooperative melting in double-stranded peptide chains through local mechanical interactions

Luca Bellino·Giuseppe Florio·Alain Goriely·Giuseppe Puglisi
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Abstract

Under an external field a double-stranded peptide chain can separate in a fragile or ductile transition. It is usually believed that these two regimes are driven either by chemical and thermal fields, or through non-local mechanical interactions. Here, we show explicitly that local mechanical interactions regulates the stability and reversibility of the cooperative/non-cooperative melting transition, which is described by a single parameter depending on an internal length scale. Our theory is applicable to a wide range of biological examples such as DNA, protein secondary structures, and the microtubules and tau proteins, for which we are able to predict the critical melting force as a function of the chain length.

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Luca Bellino, Giuseppe Florio, Alain Goriely, Giuseppe Puglisi. 2023-02-07. Cooperative melting in double-stranded peptide chains through local mechanical interactions. https://arxiv.org/abs/2302.11402

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