Correlation between the osmotic second virial coefficient and solubility for equine serum albumin and ovalbumin

Abstract

The Haas -Drenth -Wilson (HDW) (Haas et al., 1999) theoretical model was used to correlate osmotic second virial coefficient (B) values with solubility (S) values for equine serum albumin (ESA) and ovalbumin for corresponding solution conditions. The best fit from the theoretical model was compared to experimental S versus B data. B values were experimentally measured using static light scattering. Solubilities of ESA were estimated using a sitting drop method. When the experimental data for S versus B were plotted, an excellent fit for ESA was obtained according to the HDW model. The results showed that the coordination number (z) in the crystal lattice was 6, and the adjustable parameter (A) was 0.072. For ovalbumin, previously reported solubility data in aqueous ammonium sulfate solutions were utilized. The solubility data for ovalbumin were correlated with the measured B values obtained in our laboratory. The resulting best fit from the HDW model showed that z = 6 and A = 0.084.

Applications of the second virial coefficient: protein crystallization and solubility

“…However, the application of ANN and incomplete factorial solubility screens has proven to be more promising. The correlation between B and protein solubility has been presented both experimentally and theoretically for several proteins (Demoruelle et al, 2002;Gripon et al, 1997;Haas et al, 1999;Malfois et al, 1996;Neal et al, 1998;Ruppert et al, 2001). Fig.…”

“…For each protein analyzed the measured B values falling within the 'crystallization slot' (Fig. 1) Neal et al, 1998;Tessier & Lenhoff, 2003;Bonneté & Vivarè s, 2002;Demoruelle et al, 2002;Ruppert et al, 2001). An empirical correlation between B (a dilute solution parameter) and the solubility s (a phase-transition parameter) has also been demonstrated for several proteins (Demoruelle et al, 2002;Gripon et al, 1997;Guo et al, 1999).…”

Assessment and significance of protein–protein interactions during development of protein biopharmaceuticals

“…A better understanding of these interactions is of interest, not only to manage solution viscosity but also towards dealing with issues such as protein solubility (Valente et al 2005), self-association (Liu et al 2005;Minton 2005), and aggregation (Saluja et al 2007). Non-ideality parameters such as the second virial coefficient (B 22 ) (George et al 1997a, b) and the interaction parameter (k D ) (Li et al 2004), measured using conventional techniques such as AUC, SLS and dynamic light scattering (DLS), have been used as a reliable measure of intermolecular interactions in dilute solution conditions as it pertains to relating intermolecular interactions to protein precipitation (Curtis et al 1998) solubility (Demoruelle et al 2002;Valente et al 2005), and crystallization (George et al 1997a, b).…”

Rigorous analysis of static light scattering measurements on buffered protein solutions

“…The first doubts about the thermodynamic status of A 2 arose from light scattering studies reporting negative values for the osmotic second virial coefficient for protein selfinteraction [1][2][3]34]. Those reports prompted sedimentation equilibrium studies on lysozyme [35] and equine serum albumin [9] to show the ionic strength dependent decrease in B 22 to a positive, asymptotic value defined by the hard particle contribution.…”