Lu Jie, Carpenter Keith, Li Rui-Jiang, Wang Xiu-Juan, Ching Chi-Bun
Institute of Chemical and Engineering Sciences, Ayer Rajah Crescent 28, #02-08, Singapore 139959, Singapore.
Biophys Chem. 2004 Apr 1;109(1):105-12. doi: 10.1016/j.bpc.2003.10.021.
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.
对生物大分子结构的深入了解揭示了它们的功能，因此在新药设计以及工程分子以获得具有改进特性用于工业应用方面具有重要意义。尽管用于蛋白质结晶的技术已经取得了很大进展，但蛋白质结晶仍可能被视为一门艺术而非科学，成功的结晶在很大程度上仍然是经验性的且依赖于操作者。在这项工作中，一种微量量热技术已被用于通过测量过饱和溶菌酶溶液的浊点温度T(cloud)来研究液-液相分离。详细研究了离子强度和甘油对浊点温度的影响。在所研究的整个盐浓度范围内，浊点温度随氯化钠浓度单调增加。当添加甘油作为添加剂时，溶菌酶的溶解度增加，而浊点温度降低。
