果糖对莆田黑猪精液中NAGase的抑制动力学.doc

PAGE PAGE 1 果糖对莆田黑猪精液中NAGase的抑制动力学* 沈林松1 张 颖1 张伟妮1 赖育河1 黄小红1* 1福建农林大学中西兽医结合与动物医学保健福建省高校重点实验室，福建 福州 350002 摘 要 为了探讨精液中不同类型糖类物质对精子细胞中NAGase的影响，本研究以莆田黑猪精液NAGase为材料，研究精液和精液稀释液主要成分之一果糖对酶的影响。结果显示，果糖对NAGase具有浓度效应（IC50=575 mmol·L-1）。果糖对NAGase的抑制类型是可逆的非竞争性抑制，抑制常数是1.27×10-2 mmol·L-1。应用底物反应的动力学方法研究果糖对该酶的抑制动力学，建立了抑制动力学模型证明了果糖对酶的影响是快速结合再缓慢失活的过程。结论：在高浓度的抑制剂溶液中酶将完全失活，底物对酶无保护作用。图6表1参24 关键词 果糖；莆田黑猪精液；N-乙酰-β-D-氨基葡萄糖苷酶；抑制动力学 CLC Q556+.2 Inhibitory kinetics of fructose on NAGase from semen of Putian black pig* SHEN Lin-song1, ZHANG Ying1, ZHANG Wei-ni1, LAI Yu-he1，HUANG Xiao-hong1* 1University Key Lab for Integrated Chinese Traditional and Western Veterinary Medicine and Animal Healthcare in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China Abstract Objectives: In order to discuss different types of sugars affects the N-Acetyl-β-D-glucosaminidase (EC 2, NAGase) in sperm cells. Methods: In this study, NAGase from semen of Putian black pig was used as the material to study the effects of fructose which is one of the main components of the sperm and semen dilutions. The inhibition kinetics of fructose on the enzyme model was set up by using the kinetic method of substrate reaction. Results: It has been shown that the NAGase has a dose dependent of fructose (IC50=575 mmol·L-1) and the inhibition type of fructose on NAGase was reversible noncompetitive inhibition, and the inhibition constants is 1.27 ×10-2 mmol·L-1. The process of fructose on the enzyme was firstly slow deactivation then rapid combination. Conclusions: In fructose solution with high concentrations, the enzyme was completely deactivated. The substrate had no protection to the enzyme. Key words fructose；Putian black pig semen；N-Acetyl-β-D-glucosaminidase；inhibitory kinetics 收稿日期 Received: 接受日期 Accepted: *福建省科技计划项目重点项目（2012N0002）Support by the Science and Technology Major Project of Fujian Province (2012N0002) **通讯作者 Corresponding author (E-mail: xhhuang138@.) 随