Cloud-point temperature and liquid-liquid phase separation of supersaturated lysozyme solution.
The detailed understanding of the structure of biological macromolecules reveals their functions, and is thus important in the design of new medicines and for engineering molecules with improved properties for industrial applications. Although techniques used for protein crystallization have been progressing greatly, protein crystallization may still be considered an art rather than a science, and successful crystallization remains largely empirical and operator-dependent. In this work, a microcalorimetric technique has been utilized to investigate liquid-liquid phase separation through measuring cloud-point temperature T(cloud) for supersaturated lysozyme solution. The effects of ionic strength and glycerol on the cloud-point temperature are studied in detail. Over the entire range of salt concentrations studied, the cloud-point temperature increases monotonically with the concentration of sodium chloride. When glycerol is added as additive, the solubility of lysozyme is increased, whereas the cloud-point temperature is decreased.
Lu
Jie
J
Institute of Chemical and Engineering Sciences, Ayer Rajah Crescent 28, #02-08, Singapore 139959, Singapore. lujie@ices.a-star.edu.sg
Carpenter
Keith
K
Li
Rui-Jiang
RJ
Wang
Xiu-Juan
XJ
Ching
Chi-Bun
CB
D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D005990:Glycerol / Q000737:chemistry; D009113:Muramidase / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D012995:Solubility; D012996:Solutions / Q000737:chemistry; D044366:Transition Temperature
D012996:Solutions; D012965:Sodium Chloride; D009113:Muramidase; D005990:Glycerol