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arXiv · 0903.0746

Crowding effects on the structural transitions in a flexible helical homopolymer

Alexander Kudlay·Margaret S. Cheung·D. Thirumalai
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Abstract

We elucidate the structural transitions in a helical off-lattice homopolymer induced by crowding agents, as function of the number of monomers ($N$) and volume fraction ($ϕ_c$) of crowding particles. At $ϕ_c = 0$, the homopolymer undergoes transitions from a random coil to a helix, helical hairpin \textbf{HH}, and helix bundle \textbf{HB} structures depending on $N$, and temperature. Crowding induces chain compaction that can promote \textbf{HH} or \textbf{HB} formation depending on $ϕ_c$. Typically, the helical content decreases which is reflected in the decrease in the transition temperatures that depend on $ϕ_c$, $N$, and the size of the crowding particles.

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Alexander Kudlay, Margaret S. Cheung, D. Thirumalai. 2009-03-04. Crowding effects on the structural transitions in a flexible helical homopolymer. https://doi.org/10.1103/physrevlett.102.118101

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