The M32L substitution of staphylococcal nuclease: Disagreement between theoretical prediction and experimental protein stability

by Spencer, Daniel S.; Stites, Wesley E.

The M32L substitution mutation of staphylococcal nuclease was made to test the theoretical prediction by Yamaotsu, Moriguchi and Hirono that it would be approximately 1.6 kcal/mol more stable than the wild-type protein. Instead M32L and the closely related M32I mutant were 0.8 and 0.6 kcal/mol less stable than the wild-type protein, respectively. The theoretical treatment had successfully predicted the stability effects of other mutations in staphylococcal nuclease. The discrepancy found here may be due to a general problem of the theoretical treatment, such as inadequate molecular dynamics simulation time, or possibly due to more specific difficulty in assessing the strength of the sulfur-aromatic interaction that is present in the wild-type.

Journal
Journal of Molecular Biology
Volume
257
Issue
3
Year
1996
Start Page
497-499
URL
https://dx.doi.org/10.1006/jmbi.1996.0180
ISBN/ISSN
1089-8638; 0022-2836
DOI
10.1006/jmbi.1996.0180