Direct allowance for the effects of thermodynamic nonideality in the quantitative characterization of protein self-association by osmometry.
A procedure is described for the direct analysis of osmotic pressure data for reversibly dimerizing proteins that makes allowance for effects of thermodynamic nonideality on the statistical-mechanical basis of the potential-of-mean-force between molecules. Detailed consideration is also given to calculation of the magnitudes of the required virial coefficients. After illustration of the approach with analysis of simulated osmotic pressure data, the method is used to obtain dimerization constants from published osmotic pressure data for soybean proteinase inhibitor, hemoglobin and alpha-chymotrypsin.
School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia.
Peter R
PR
Wills
Donald J
DJ
Winzor
D002462:Cell Membrane / Q000378:metabolism; D002918:Chymotrypsin / Q000737:chemistry / Q000378:metabolism; D006454:Hemoglobins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D009997:Osmotic Pressure; D011480:Protease Inhibitors / Q000737:chemistry / Q000378:metabolism; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D030262:Soybean Proteins / Q000737:chemistry / Q000378:metabolism; D013025:Glycine max / Q000201:enzymology; D055672:Static Electricity; D013816:Thermodynamics
D006454:Hemoglobins; D011480:Protease Inhibitors; D030262:Soybean Proteins; D002918:Chymotrypsin