Protein Interactions in Solution Characterized by Light and Neutron Scattering:
Comparison of Lysozyme and Chymotrypsinogen
5. Protein-protein interactions and crystallization - conclusions (this page)
Protein-protein interactions and crystallization - conclusions
- The second virial coefficients of two widely used proteins - lysozyme and chymotrypsinogen were characterized in depth by SLS and SANS as a function of pH and ionic strength.
- A very good correlation of the virial coefficients data obtained by SANS and SLS was established while all values are calculated without fitting parameters.
- Two different patterns of virial coefficient change were observed. The virial coefficients with lysozyme always decrease with increase of pH and lysozyme concentration, while with chymotrypsinogen there is a crossover point at pH 5.2 where the attractive electrostatics take over.
- The data can be reasonably approximated by DLVO-type of modeling, but an explicit description is possible only by accounting for the structural details of the protein.
- The results of protein precipitation and crystallization experiments are in qualitative correlation with the patterns of the virial coefficients and demonstrate that interaction mapping could help outline new crystallization regions.
The data open the way to further theoretical description of the long-ranged and short-ranged intra-molecular interactions of proteins and better understanding of their crystallization behavior.
- O. D. Velev, E. W. Kaler and A. M. Lenhoff, Biophys. J., 75, 2682 (1998). "Protein Interactions in Solution Characterized by Light and Neutron Scattering: Comparison of Lysozyme and Chymotrypsinogen" Get it on the web >>>
- B. L. Neal, D. Asthagiri, O. D. Velev, A. M. Lenhoff, and E. W. Kaler, J. Cryst. Growth, 196, 377 (1999). "Why is the Osmotic Second Virial Coefficient Related to Protein Crystallization?"
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© Copyright O. D. Velev et al. 1999