Correlation of Second Virial Coefficients and Solubilities Useful in Protein Crystal Growth
The osmotic second virial coefficient, B, is a dilute solution parameter, so one may wonder what relationships exist among B and the many facets of protein crystal growth (PCG). In particular, knowledge of how a protein's solubility (S) depends on solution variables such as temperature, pH and ionic strength is very useful for finding optimum conditions for the PCG experiment. In this work, a correlation between the second virial coefficient and protein solubility is shown for ovalbumin and lysozyme solutions. The data presented suggest significant correlation between B and S as a function of crystallizing salt type and concentration, pH and temperature. The data are presented both in graphical and tabular form so that it maybe useful to researchers desiring to develop and test detailed models for protein interactions.