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Two-dimensional structure in a generic model of triangular proteins and protein trimers

Philip J. Camp·Peter D. Duncan
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Abstract

Motivated by the diversity and complexity of two-dimensional crystals formed by triangular proteins and protein trimers, we have investigated the structures and phase behavior of hard-disk trimers. In order to mimic specific binding interactions, each trimer possesses on `attractive' disk which can interact with similar disks on other trimers via an attractive square-well potential. At low density and low temperature, the fluid phase mainly consists of tetramers, pentamers, or hexamers. Hexamers provide the structural motif for a high-density, low-temperature periodic solid phase, but we also identify a metastable periodic structure based on a tetramer motif. At high density there is a transition between orientationally ordered and disordered solid phases. The connections between simulated structures and those of 2D protein crystals -- as seen in electron microscopy -- are briefly discussed.

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Philip J. Camp, Peter D. Duncan. 2006-01-05. Two-dimensional structure in a generic model of triangular proteins and protein trimers. https://doi.org/10.1103/physreve.73.046111

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