用参数Z表征疏水色谱中脲浓度与蛋白质分子的构象变化

研究了５种标准蛋白在流动相中含有不同脲浓度条件下的疏水色谱保留行为。当脲浓度不变时，蛋白质的保留仍然服从计量置换保留模型，并可测定在该特定脲浓度条件下蛋白质的Ｚ值。计量置换参数Ｚ可作为疏水色谱中生物大分子的构象变化的表征。

An Investigation of the Relationship Between Concentration of Urea and Molecular Conformation of Biopolymers in Hydrophobic Interaction Chromatography by Using a Characterization Parameter Z

The retention behavior of five proteins in hydrophobic interaction chromatography (HIC) under the mobile phase of (NH4)2SO4-KH2PO4 containing various urea concentrations was investigated. It was found that the retention of these proteins follow the stoichiometric displacement model for retention (SDM-R), so long as the urea concentration remains con- stant in the mobile phase. The Z values of these proteins in HIC can be used as a characteri- zation parameter of the change in the molecular conformation of these proteins. The Z values of these proteins decrease with the increasing concentration of urea in the mobile phase. Be- sides molecular con formation, the changes in the Z values of these proteins may also be caused from the participation of urea in the stoichiometric displacement process between pro- tein and the displacing agent molecules. Whether the change in the Z valt1es is continuous or not, it reflects the same change tendency in the molecular conformation of proteins.