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Stability of Designed Proteins Against Mutations

R. A Broglia·G. Tiana·H. E. Roman·E. Vigezzi·E. I. Shakhnovich
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Abstract

The stability of model proteins with designed sequences is assessed in terms of the number of sequences (obtained from the designed sequence through mutations), which fold into 5the ``native'' conformation. By a complete enumeration of the total number of sequences obtained by introducing up to 4 point mutations and up to 7 composition--conserving mutations (swapping of amino acids) in a 36mers chain, it is found that there are $10^8-10^9$ sequences which in the folding process target onto the ``native'' conformation. Consequently, proteins with designed sequences display a remarkable degree of stability and, to a large extent, of designability.

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R. A Broglia, G. Tiana, H. E. Roman, E. Vigezzi, E. I. Shakhnovich. 1998-09-30. Stability of Designed Proteins Against Mutations. https://doi.org/10.1103/physrevlett.82.4727

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