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arXiv · cond-mat/9609062

Freezing Transition of Compact Polyampholytes

Vijay S. Pande·Alexander Yu. Grosberg·Chris Joerg·Mehran Kardar·Toyoichi Tanaka
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Abstract

Polyampholytes (PAs) are heteropolymers with long range Coulomb interactions. Unlike polymers with short range forces, PA energy levels have non-vanishing correlations and are thus very different from the Random Energy Model (REM). Nevertheless, if charges in the PA globule are screened as in a regular plasma, PAs freeze in REM fashion. Our results shed light on the potential role of Coulomb interactions in folding and evolution of {\it proteins}, which are weakly charged PAs, in particular making connection with the finding that sequences of charged amino acids in proteins are not random.

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Vijay S. Pande, Alexander Yu. Grosberg, Chris Joerg, Mehran Kardar, Toyoichi Tanaka. 1996-09-05. Freezing Transition of Compact Polyampholytes. https://doi.org/10.1103/physrevlett.77.3565

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