Characterizing Protein-Protein Interactions via Static Light Scattering: Nonspecific Interactions

摘要

The quantitative characterization of nonspecific protein-protein interactions is essential in understanding basic biomolecular function as well as the development of new biotechnology products. Virial coefficients indicate the overall attraction or repulsion between molecules, providing a general measure of the intermolecular potential as mediated by the solvent. In biotechnology applications, fine-tuning self-virial coefficients A_2 (SVC) and cross-virial coefficients AH (CVC) by adjusting pH, ionicstrength, and concentrations of various excipients in the buffer can help set optimal conditions for stability, purification, and crystallization. For example, George and Wilson have shown that crystallization typically occurs within a small range of A2values corresponding to a weak attraction. Luisi et al. have demonstrated the correlation between A_2 (measured at low concentrations) and opalescence (occurring at high concentration). Ho et al. found a strong correlation between A_2 and aggregation during renaturation. All of these point to the importance of measuring and interpreting virial coefficients for protein characterization.