PROBES OF MECHANISM OF ZYMOGEN CATALYSIS
PROBES OF MECHANISM OF ZYMOGEN CATALYSIS
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DOI：
10.1021/bi00607a016
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发表时间：
1978-01-01
期刊：
影响因子：
2.9
通讯作者：
WALSH, KA
中科院分区：
文献类型：
--
作者：
LONSDALEECCLES, JD;NEURATH, H;WALSH, KA
John D. Lonsdale-Eccles,! Hans Neurath, and Kenneth A. Walsh* abstract: Trypsinogen and chymotrypsinogen hydrolyze p-nitrophenyl esters of several peptides and fe/T-butyloxycarbonyl amino acids. The best substrate foundfor chymotrypsinogen was Boc-Ala-ONp and for trypsinogen Z-Gly-Hyp-Gly-ONp. Comparison of the kinetic parameters indi-cates that in the zymogens the catalytic site is distorted and reduced in effectiveness by about two orders of magnitude, in addition to a 10 000-fold decrease in catalysis due to a dis-IC-inetic studies of the catalytic activity of zymogens have indicated that the major change in the zymogen/enzyme transformation involves the development of a primary binding site (also called the tosyl hole or Pi binding site; Gertler et al., 1974; Kerr et al., 1975). Since the zymogen reacts more slowly than the enzyme with methanesulfonyl fluoride (Morgan et al., 1972), and since acyl-zymogens deacylate more slowly than acyl-enzymes (Kerr et al., 1975), it was suggested that in the zymogen the oxyanion hole is also distorted (Kerr et al., 1976). Similar conclusions have been drawn from studies employing
