Dong Xiao-Yan, Huang Yan, Sun Yan
Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
J Biotechnol. 2004 Oct 19;114(1-2):135-42. doi: 10.1016/j.jbiotec.2004.06.012.
The refolding kinetic behavior of denatured-reduced lysozyme in the presence of folding aids (acetamide, acetone, thiourea, L-arginine or glycerol) was studied utilizing a simplified model describing the competition between first-order folding reaction and third-order aggregation. It was found that the protein folding aids could be categorized into two groups. One of them at proper concentrations, such as acetamide, acetone, thiourea and L-arginine, stabilized unfolded protein or folding intermediates. In the presence of these additives, the folding rate decreased with increasing their concentration, and there existed a concentration where the aggregation rate constant was minimized. So, there was an optimum concentration for the folding aids to produce a high yield. The other group was protein stabilizers such as glycerol. In the presence of this kind of folding aids, both the refolding rate and yield were enhanced by increasing their concentration to a proper value. Moreover, their effect on improving protein refolding was additive to those of the first group. So the cooperative application of the two kinds of folding aids could result in favorable refolding rate and yield of protein.
利用一个描述一级折叠反应和三级聚集之间竞争的简化模型，研究了在折叠助剂（乙酰胺、丙酮、硫脲、L-精氨酸或甘油）存在下变性还原溶菌酶的重折叠动力学行为。结果发现，蛋白质折叠助剂可分为两类。其中一类在适当浓度下，如乙酰胺、丙酮、硫脲和L-精氨酸，能稳定未折叠的蛋白质或折叠中间体。在这些添加剂存在下，折叠速率随其浓度增加而降低，且存在一个使聚集速率常数最小的浓度。因此，折叠助剂存在一个产生高产率的最佳浓度。另一类是蛋白质稳定剂，如甘油。在这类折叠助剂存在下，通过将其浓度增加到适当值，重折叠速率和产率均会提高。此外，它们对改善蛋白质重折叠的作用与第一类助剂具有加和性。因此，两类折叠助剂的协同应用可使蛋白质获得良好的重折叠速率和产率。
