N-乙酰氨基葡萄糖转移酶Ⅲ和Ⅴ必需基团的研究(英文)  

Study on the essential groups of N-acetylglucosaminyltransferase Ⅲ and Ⅴ

作　　者：姜安丽[1] 安蔚[1] 王泽平[1] 马培珍[1] 

机构地区：[1]泰山医学院生物化学教研室,山东泰安271000

出　　处：《泰山医学院学报》2000年第2期141-143,共3页Journal of Taishan Medical College

摘　　要：目的　研究化学修饰剂对N 乙酰氨基葡萄糖转移酶Ⅲ和Ⅴ活性的影响以探讨这两种酶的必需基团。方法　采用七种化学修饰剂分别修饰N 乙酰氨基葡萄糖转移酶Ⅲ和Ⅴ中的一些基团 ,用高效液相法测定酶的活性。结果　巯基、羧基、吲哚基和胍基被修饰后 ,N 乙酰氨基葡萄糖转移酶Ⅲ活性丧失 ,而氨基、羧基和吲哚基被修饰后 ,N 乙酰氨基葡萄糖转移酶Ⅴ活性丧失。结论　结果表明羧基、吲哚基和胍基是N 乙酰氨基葡萄糖转移酶Ⅲ的必需基团 ;氨基、羧基和吲哚基是N 乙酰氨基葡萄糖转移酶Ⅴ的必需基团。根据结果可推测羧基、吲哚基可能与酶的底物结合部位有关 ,而胍基、氨基分别是NObjective: The effects of the chemical modifiers on N acetylglucosaminyltransferase (GnT) Ⅲ and V activities were studied to learn the essential groups of the enzymes. Methods: Seven chemical modifiers were used to modify the sulfhydryl, amino, hydroxyl, guanido, carboxyl, indolyl, imidazolyl groups of GnT Ⅲ, Ⅴ respectively. The activities of the enzymes were detected by using HPLC. Results: It was found that GnT Ⅲ activity was inactivated significantly after the sulfhydryl, carboxyl, indolyl, and guanido groups had been modified while GnT Ⅴactivity was nullified after the amino, carboxyl and indolyl groups had been modified by the modifiers. Conclusion: The results indicates that carboxyl, indolyl and guanido groups might be the essential groups of GnT Ⅲ and amino, carboxyl and indolyl groups might be the essential groups of GnT Ⅴ. It suggests that carboxyl and indolyl groups are involved in the substrate binding site both GnT Ⅲ and Ⅴ, and that guanido and amino groups are essential for the catalytic region of GnT Ⅲ and Ⅴ respectively.

关 键 词：N-乙酰氨基葡萄糖转移酶 化学修饰 必要基团 

分 类 号：R341[医药卫生—基础医学]