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Elastically-Driven Linker Aggregation between Two Semi-Flexible Polyelectrolytes

I. Borukhov·R. F. Bruinsma·W. M. Gelbart·A. J. Liu
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Abstract

The behavior of mobile linkers connecting two semi-flexible charged polymers, such as polyvalent counterions connecting DNA or F-actin chains, is studied theoretically. The chain bending rigidity induces an effective repulsion between linkers at large distances while the inter-chain electrostatic repulsion leads to an effective short range inter-linker attraction. We find a rounded phase transition from a dilute linker gas where the chains form large loops between linkers to a dense disordered linker fluid connecting parallel chains. The onset of chain pairing occurs within the rounded transition.

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I. Borukhov, R. F. Bruinsma, W. M. Gelbart, A. J. Liu. 2001-01-10. Elastically-Driven Linker Aggregation between Two Semi-Flexible Polyelectrolytes. https://doi.org/10.1103/physrevlett.86.2182

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