Protein stability in mixed solvents: a balance of contact interaction and excluded volume.

ABSTRACT: Changes in excluded volume and contact interaction with the surface of a protein have been suggested as mechanisms for the changes in stability induced by cosolvents. The aim of the present paper is to present an analysis that combines both effects in a quantitative manner. The result is that both processes are present in both stabilizing and destabilizing interactions and neither can be ignored. Excluded volume was estimated using accessible surface area calculations of the kind introduced by Lee and Richards. The change in excluded volume on unfolding, deltaX, is quite large. For example, deltaX for ribonuclease is 6.7 L in urea and approximately 16 L in sucrose. The latter number is greater than the molar volume of the protein. Direct interaction with the protein is represented as the s

SUBMITTER: Schellman JA 

PROVIDER: S-EPMC1303070 | biostudies-literature | 2003 Jul

REPOSITORIES: biostudies-literature