Spector L B
Proc Natl Acad Sci U S A. 1980 May;77(5):2626-30. doi: 10.1073/pnas.77.5.2626.
Facts relating to the mechanism of phosphoryl transfer by acetate kinase (ATP:acetate phosphotransferase, EC 2.7.2.1) are reviewed. They point to the existence of at least one experimentally established phosphoenzyme (E-P) intermediate on the reaction pathway. Sterically, the phosphoryl transfer occurs with a net inversion of the configuration of the phosphorus atom. These facts are best in accord with a triple-displacement mode of action for acetate kinase, with two E-P intermediates and three steric inversions on phosphorus. It follows that a second E-P for acetate kinase must exist.
本文综述了与乙酸激酶(ATP:乙酸磷酸转移酶,EC 2.7.2.1)磷酸转移机制相关的事实。这些事实表明,在反应途径上至少存在一种经实验证实的磷酸化酶(E-P)中间体。从空间结构上看,磷原子构型发生净反转时会发生磷酸转移。这些事实最符合乙酸激酶的三取代作用模式,即存在两个E-P中间体且磷原子发生三次空间构型反转。由此可见,乙酸激酶必然存在第二种E-P中间体。