PUGNAc对罗非鱼肝脏NAGase的抑制动力学  

The inhibitory kinetics of PUGNAc on NAGase from tilapia liver

作　　者：申奔龙 陈晓佳[1] 黄小红[1] 张伟妮[1,2] SHEN Benlong;CHEN Xiaojia;HUANG Xiaohong;ZHANG Weini(University Key Laboratory for Integrated Chinese Traditional and Western Veterinary Medicine and Animal Healthcare;Institute of Oceanology,Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China)

机构地区：[1]福建农林大学中西兽医结合与动物保健福建省高校重点实验室 [2]福建农林大学海洋研究院,福建福州350002

出　　处：《福建农林大学学报（自然科学版）》2020年第3期366-371,共6页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

基　　金：国家自然科学基金资助项目(31572484);福建省自然科学基金资助项目(2015J01605).

摘　　要：探究PUGNAc对罗非鱼肝脏N-乙酰-β-D-氨基葡萄糖苷酶(NAGase)的抑制作用.通过建立PUGNAc对NAGase的抑制动力学模型,表明PUGNAc对NAGase的抑制是一种缓慢的、可逆的反应,IC50为0.18μmol·L^-1,抑制类型为混合性;与自由酶结合的抑制平衡常数KI为0.110μmol·L^-1,KIS为0.827μmol·L^-1;微观速率常数k+0大于k′+0,表明游离酶分子比抑制剂存在下的酶-底物复合物更脆弱,从而推测底物的存在对PUGNAc抑制下的NAGase起着保护作用.The inhibitory kinetics of PUGNAc on NAGase from tilapia liver was set up. The results showed that, the inhibition effect of PUGNAc on the enzyme was a slow reversible reaction, IC50 was 0.18 μmol·L^-1, the type of inhibition was mixed. The inhibitory equilibrium constant KI, combined with the free enzyme was 0.110 μmol·L^-1 and the KIS value was 0.827 μmol·L^-1. The microrate constant k+0 was higher than k′+0, indicating that the free enzyme molecule was more fragile than the PUGNAc enzyme-substrate complex. The results suggested that the presence of the substrate plays a protective role for the inhibition of NAGase by PUGNAc.

关 键 词：PUGNAc 抑制动力学 N-乙酰-Β-D-氨基葡萄糖苷酶 罗非鱼 

分 类 号：S917.4[农业科学—水产科学]