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Thermodynamic stability of folded proteins against mutations

H. J. Bussemaker·D. Thirumalai·J. K. Bhattacharjee
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Abstract

By balancing the average energy gap with its typical change due to mutations for protein-like heteropolymers with M residues, we show that native states are unstable to mutations on a scale M* ~ (lambda/sigma_mu)^(1/zeta_s), where lambda is the dispersion in the interaction free energies and sigma_mu their typical change. Theoretical bounds and numerical estimates (based on complete enumeration on four lattices) of the instability exponent zeta_s are given. Our analysis suggests that a limiting size of single-domain proteins should exist, and leads to the prediction that small proteins are insensitive to random mutations.

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H. J. Bussemaker, D. Thirumalai, J. K. Bhattacharjee. 1997-09-05. Thermodynamic stability of folded proteins against mutations. https://doi.org/10.1103/physrevlett.79.3530

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