Experimental determination of second virial coefficients by small-angle X-ray scattering: a problem revisited.

Experimental determination of second virial coefficients by small-angle X-ray scattering: a problem revisited.
Eur Biophys J. 2019 Oct 31;:
Authors: Mrozowich T, Winzor DJ, Scott DJ, Patel TR
Abstract
This investigation examines the validity of employing single-solute theory to interpret SAXS measurements on buffered protein solutions-the current practice despite the necessity to regard the buffer components as additional non-scattering solutes rather than as part of the solvent. The present study of bovine serum albumin in phosphate-buffered saline supplemented with 20-100 g/L sucrose as small cosolute has certainly verified the prediction that the experimentally obtained second virial coefficient should contain protein-cosolute contributions. Nevertheless, the second virial coefficient determined for protein solutions supplemented with high cosolute concentrations on the basis of single-solute theory remains a valid means for identifying conditions conducive to protein crystallization, because the return of a slightly negative second virial coefficient based on single-solute theory [Formula: see text] still establishes the existence of slightly associative interactions between protein molecules, irrespective of the molecular source-protein self-interactions and/or protein-cosolute contributions.
PMID: 31667558 [PubMed - as supplied by publisher]

Source: European Biophysics Journal : EBJ - October 30, 2019 Category: Physics Authors: Mrozowich T, Winzor DJ, Scott DJ, Patel TR Tags: Eur Biophys J Source Type: research