产物及其类似物对锯缘青蟹NAGase酶活力的影响  

Inhibitory effects of product and its analogs on N-acetyl-β-D-glucosaminidase from green crab(Scylla serrata)

作　　者：杨学敏[1] 张继平[2] 谢进金[3] 颜雅雯[1] 陈清西[1] 

机构地区：[1]厦门大学细胞生物学与肿瘤细胞工程教育部重点实验室厦门大学生命科学学院 [2]广东佛山科学技术学院生命科学学院,广东佛山528231 [3]泉州师范学院生物系,福建泉州362000

出　　处：《台湾海峡》2006年第2期229-233,共5页Journal of Oceanography In Taiwan Strait

基　　金：国家自然科学基金资助项目(40576066);厦门大学细胞生物学与肿瘤细胞工程教育部重点实验室开放基金资助项目(2005101)

摘　　要：以产物N-乙酰-β-D-氨基葡萄糖(NAG)及其类似物-葡萄糖(glu)、半乳糖(gal)、果糖(fru)和蔗糖(suc)为效应物,研究它们对锯缘青蟹N-乙酰-β-D-氨基葡萄糖苷酶(NAGase)活力的影响及抑制作用机理.结果表明,上述效应物对酶均表现为可逆的抑制作用.NAG有较强的抑制作用,其IC50为0.011 mol/dm3.但产物类似物对该酶的抑制作用均弱于NAG.NAG对该酶的抑制作用机理表现为反竞争性抑制,抑制常数KIS为4.37×10-3mol/dm3;glu、gal、suc则表现为非竞争性抑制,抑制常数KI分别为0.125、0.394、0.474 mol/dm3;而fru则表现为竞争性抑制,抑制常数KI为0.455mol/dm3.In this paper, the inhibitory effect and mechanism of product and its analogs on the activity of NAGase from green crab （ Scylla serrata） have been studied. The results show that NAG, glucose, galactose, frurose and sucrose can inhibit the enzyme activity for the hydrolysis of pNP-NAG and its inhibition is reversible reaction with remaining activity. Product （NAG） is most potent in the tested compounds. The inhibitor concentration leading to 50% of enzyme activity lost （IC50） was estimated to be 0.01 1 mol/dm^3. However, the inhibitory ability of product analogs was much weaker than that of NAG. The inhibitory type of NAG on the enzyme was found to be uncompetitive and the inhibitory constant （KIS） was determined to be 4.37 × 10^-3mol/dm^3. Glucose, galactose, sucrose were classified as noncompetitive inhibitors and their inhibitory constant were determined to be 0. 125, 0.394 and 0. 474 mol/dm^3 , respectively. Frurose was classified as competitive and the inhibitory constant was determined to be 0. 455 mol/dm^3.

关 键 词：海洋生物 N-乙酰-Β-D-氨基葡萄糖苷酶 实验研究 锯缘青蟹 产物及其类似物 抑制机理 

分 类 号：Q556.1[生物学—生物化学]