3-磷酸甘油酸及其他底物类似物与异柠檬酸裂解酶的乙醛酸和琥珀酸结合位点的相互作用。

The interaction of 3-phosphoglycerate and other substrate analogs with the glyoxylate- and succinate-binding sites of isocitrate lyase.

作者信息

Ko Y H, Vanni P, McFadden B A

机构信息

Biochemistry and Biophysics Program, Washington State University, Pullman 99164-4660.

出版信息

Arch Biochem Biophys. 1989 Oct;274(1):155-60. doi: 10.1016/0003-9861(89)90426-8.

DOI:10.1016/0003-9861(89)90426-8

PMID:2673042

Abstract

The gene for isocitrate lyase from Escherichia coli has recently been cloned and sequenced. However, knowledge of this enzyme from E. coli is limited. Because of the possible role of 3-phosphoglycerate as a metabolic inhibitor of isocitrate lyase in E. coli, a detailed analysis of this compound as an inhibitor is reported in this paper. Kinetic data suggest that 3-phosphoglycerate is an analog of isocitrate (or glyoxylate) and also that it competes with succinate, or succinate analogs, by interfering with their binding to the enzyme. This could be due to the steric bulk of the phosphate moiety of 3-phosphoglycerate extending in the direction of and over the succinate-binding site. The interaction of other substrate analogs, including glycolate, oxalate, phosphoenolpyruvate, and cis-aconitate, with isocitrate lyase from E. coli is also characterized.

摘要

来自大肠杆菌的异柠檬酸裂合酶基因最近已被克隆和测序。然而，对大肠杆菌中这种酶的了解有限。由于3-磷酸甘油酸可能作为大肠杆菌中异柠檬酸裂合酶的代谢抑制剂，本文报道了对该化合物作为抑制剂的详细分析。动力学数据表明，3-磷酸甘油酸是异柠檬酸（或乙醛酸）的类似物，并且它还通过干扰琥珀酸或琥珀酸类似物与酶的结合来与它们竞争。这可能是由于3-磷酸甘油酸的磷酸基团的空间体积朝着琥珀酸结合位点的方向延伸并覆盖了该位点。还对包括乙醇酸、草酸盐、磷酸烯醇丙酮酸和顺乌头酸在内的其他底物类似物与大肠杆菌异柠檬酸裂合酶的相互作用进行了表征。