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arXiv · 1503.05486

Molecular recognition by van der Waals interaction between polymers with sequence-specific polarizabilities

Bing-Sui Lu·Ali Naji·Rudolf Podgornik
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Abstract

We analyze van der Waals interactions between two rigid polymers with sequence-specific, anisotropic polarizabilities along the polymer backbones, so that the dipole moments fluctuate parallel to the polymer backbones. Assuming that each polymer has a quenched-in polarizability sequence which reflects, for example, the polynucleotide sequence of a double-stranded DNA molecule, we study the van der Waals interaction energy between a pair of such polymers with rod-like structure for the cases where their respective polarizability sequences are (i) distinct and (ii) identical, with both zero and non-zero correlation length of the polarizability correlator along the polymer backbones in the latter case. For identical polymers, we find a novel $r^{-5}$ scaling behavior of the van der Waals interaction energy for small inter-polymer separation $r$, in contradistinction to the $r^{-4}$ scaling behavior of distinct polymers, with furthermore a pronounced angular dependence favoring attraction between sufficiently aligned identical polymers. Such behavior can assist the molecular recognition between polymers.

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Bing-Sui Lu, Ali Naji, Rudolf Podgornik. 2015-03-18. Molecular recognition by van der Waals interaction between polymers with sequence-specific polarizabilities. https://doi.org/10.1063/1.4921892

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