The correlation between protein stability and dipole moment: a critical test.
Improving the stability of proteins is a major aim in basic and applied protein science. Querol and coworkers calculated changes in the quasi-electric dipole moment of a protein and used it as a simple criterion to predict stabilizing charge mutations. They employed this method to propose for the bacterial cold shock protein Bc-Csp a number of charge mutations that should have a strong influence on stability. We produced eight variants of Bc-Csp with such mutations and measured their stabilities experimentally. However, we could not find a correlation between the stability and the quasi dipole moment of these variants. Possibly, the quasi dipole moment reflects only a secondary aspect of the changes that are caused by charge mutations in a protein.
Wunderlich
Michael
M
Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth D-95440 Bayreuth, Germany.
Schmid
Franz X
FX
D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D002152:Calorimetry, Differential Scanning; D002942:Circular Dichroism; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000235:genetics; D006358:Hot Temperature; D009154:Mutation; D011487:Protein Conformation; D055672:Static Electricity; D013816:Thermodynamics
D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; C407094:cold shock protein, Bacillus