Kinetic studies of carboxypeptidase Y. III. Action on ester, amide, and anilide substrates and the effects of some environmental factors.
Kinetic studies of carboxypeptidase Y. III. Action on ester, amide, and anilide substrates and the effects of some environmental factors.
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DOI：
10.1093/oxfordjournals.jbchem.a130948
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发表时间：
1975-09
影响因子：
2.7
通讯作者：
Y. Bai;R. Hayashi;T. Hata
中科院分区：
文献类型：
--
作者：
Y. Bai;R. Hayashi;T. Hata
给出了羧肽酶 Y 水解酯、酰胺和苯胺底物的动力学参数。 kcat/Km 值与胰凝乳蛋白酶 [EC 3.4.21.1] 的值兼容，但有一些例外。建议 pK 约为 5.8 的一个可电离基团参与游离酶水解所有底物（包括肽底物）的过程。此外，羟氨解作用和氧化氘的动力学同位素效应表明，有一些保留，反应机制是通过形成酰基中间体进行的。
Kinetic parameters of carboxypeptidase Y are given for the hydrolyses of ester, amide, and anilide substrates. The kcat/Km values were compatible with those of chymotrypsin [EC 3.4.21.1] with a few exceptions. One ionizable group with a pK of around 5.8 was suggested to be involved in the free enzyme in hydrolyzing all the substrates, including peptide substrates. In addition, hydroxylaminolysis and the kinetic isotope effects of deuterium oxide indicated, with some reservations, a reaction mechanism which proceeds via the formation of an acyl intermediate.