de Riel J K, Paulus H
Biochemistry. 1978 Nov 28;17(24):5146-50. doi: 10.1021/bi00617a012.
The mechanism of desensitization of glycerol kinase to allosteric inhibition by fructose 1,6-bisphosphate caused by salt, urea, and high pH has been examined in the light of the model proposed in an earlier paper [de Riel, J. K., and Paulus H. (1978), Biochemistry 17] relating subunit dissociation and ligand binding. KCl (0.4 M) causes a tenfold decrease in the affinity of tetrameric glycerol kinase for fructose, 1,6-bisphosphate but has no significant effect on the dissociation process itself. Urea (2 M) causes a large increase in the equilibrium constant for the dissociation of the glycerol kinase tetramer to dimer but has no effect on the affinity of the tetramer for the allosteric inhibitor. High pH (9--10) has only a small effect on the subunit dissociation constant but greatly reduces the rates of subunit association and dissociation. Desensitization of glycerol kinase to allosteric inhibition can thus occur by three different mechanisms, two of which are directly related to the polysteric nature of the enzyme.
根据之前一篇论文[de Riel, J. K., and Paulus H. (1978), Biochemistry 17]中提出的关于亚基解离和配体结合的模型，研究了盐、尿素和高pH值导致甘油激酶对1,6 -二磷酸果糖变构抑制脱敏的机制。KCl（0.4 M）使四聚体甘油激酶对1,6 -二磷酸果糖的亲和力降低了10倍，但对解离过程本身没有显著影响。尿素（2 M）使甘油激酶四聚体解离为二聚体的平衡常数大幅增加，但对四聚体对变构抑制剂的亲和力没有影响。高pH值（9 - 10）对亚基解离常数只有很小的影响，但大大降低了亚基缔合和解离的速率。因此，甘油激酶对变构抑制的脱敏可以通过三种不同的机制发生，其中两种机制与酶的多聚体性质直接相关。
