The effect of ionic strength, temperature, and pressure on the interaction potential of dense protein solutions: from nonlinear pressure response to protein crystallization.
Understanding the intermolecular interaction potential, V(r), of proteins under the influence of temperature, pressure, and salt concentration is essential for understanding protein aggregation, crystallization, and protein phase behavior in general. Here, we report small-angle x-ray scattering studies on dense lysozyme solutions of high ionic strength as a function of temperature and pressure. We show that the interaction potential changes in a nonlinear fashion over a wide range of temperatures, salt, and protein concentrations. Neither temperature nor protein and salt concentration lead to marked changes in the pressure dependence of V(r), indicating that changes of the water structure dominate the pressure dependence of the intermolecular forces. Furthermore, by analysis of the temperature, pressure, and ionic strength dependence of the normalized second virial coefficient, b2, we show that the interaction can be fine-tuned by pressure, which can be used to optimize b2 values for controlled protein crystallization.
Fakultät Physik/DELTA, TU Dortmund, Dortmund, Germany.
Johannes
J
Möller
Martin A
MA
Schroer
Mirko
M
Erlkamp
Sebastian
S
Grobelny
Michael
M
Paulus
Sebastian
S
Tiemeyer
Florian J
FJ
Wirkert
Metin
M
Tolan
Roland
R
Winter
D000818:Animals; D002645:Chickens; D003460:Crystallization; D009113:Muramidase / Q000737:chemistry* / Q000378:metabolism*; D017711:Nonlinear Dynamics; D009994:Osmolar Concentration; D011312:Pressure; D011485:Protein Binding / Q000187:drug effects; D053838:Scattering, Small Angle; D012965:Sodium Chloride / Q000494:pharmacology; D012996:Solutions; D013696:Temperature; D014961:X-Ray Diffraction
D012996:Solutions; D012965:Sodium Chloride; D009113:Muramidase