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Geometry and symmetry presculpt the free-energy landscape of proteins

Trinh Xuan Hoang·Antonio Trovato·Flavio Seno·Jayanth R. Banavar·Amos Maritan
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Abstract

We present a simple physical model which demonstrates that the native state folds of proteins can emerge on the basis of considerations of geometry and symmetry. We show that the inherent anisotropy of a chain molecule, the geometrical and energetic constraints placed by the hydrogen bonds and sterics, and hydrophobicity are sufficient to yield a free energy landscape with broad minima even for a homopolymer. These minima correspond to marginally compact structures comprising the menu of folds that proteins choose from to house their native-states in. Our results provide a general framework for understanding the common characteristics of globular proteins.

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Trinh Xuan Hoang, Antonio Trovato, Flavio Seno, Jayanth R. Banavar, Amos Maritan. 2004-05-25. Geometry and symmetry presculpt the free-energy landscape of proteins. https://doi.org/10.1073/pnas.0402525101

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