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arXiv · 0810.0415

How knots influence properties of proteins

Joanna I. Sułkowska·Piotr Sułkowski·P. Szymczak·Marek Cieplak
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Abstract

Molecular dynamics studies within a coarse-grained structure based model were used on two similar proteins belonging to the transcarbamylase family to probe the effects in the native structure of a knot. The first protein, N-acetylornithine transcarbamylase, contains no knot whereas human ormithine transcarbamylase contains a trefoil knot located deep within the sequence. In addition, we also analyzed a modified transferase with the knot removed by the appropriate change of a knot-making crossing of the protein chain. The studies of thermally- and mechanically-induced unfolding processes suggest a larger intrinsic stability of the protein with the knot.

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Joanna I. Sułkowska, Piotr Sułkowski, P. Szymczak, Marek Cieplak. 2008-10-02. How knots influence properties of proteins. https://doi.org/10.1073/pnas.0805468105

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