2-氯-4-硝基苯-麦芽三糖苷作为α-淀粉酶底物的实验研究  

Experimental study on 2-chloro-4-nitrophenyl-alpha-D-maltotrioside as substrate of alpha-amylase

作　　者：张孝山[1] 帅真[2] 李明润[1] 关俊玲[1] 何庆[1] 杨彬[2] 徐海津[2] 

机构地区：[1]天津市医药科学研究所,天津300070 [2]天津市临床检验中心

出　　处：《天津医科大学学报》2002年第1期26-29,共4页Journal of Tianjin Medical University

基　　金：天津市卫生局科研基金资助 (课题号 :96KY36)

摘　　要：目的 :研究α -淀粉酶及其底物2 -氯 -4 -硝基苯 -麦芽三糖苷 (CNP -G3)酶促反应过程中的激动剂、抑制剂、最适 pH、米氏常数等。方法 :以测定酶促反应速度的方式分别进行研究。结果 :阳离子中仅钙离子和氨离子对α -淀粉酶有轻度的激活作用 ,阴离子中的氯离子对α -淀粉酶有强大的激活作用 ,约是迭氮钠的4倍 ,醋酸离子也有弱激活作用 ,硫酸、磷酸氢、碳酸离子无激活作用 ;乙二胺四乙酸是酶的强抑制剂 ;酶的最适pH为5.9～6.1 ;酶以CNP -G3为底物时的Km值约为0.22mmol/L ;麦芽糖对α -淀粉酶有显著的抑制作用 ;EGTA为钙离子螯合剂 ,可调节反应速率。结论 :α -淀粉/CNP -G3酶促反应系统研究可用于酶活性和激动剂测定。Objective:To investigate the effects of agonist, inhibitor, optimum pH and km value in the enzyme-promoting course of reaction of amylase using 2-chloro-4-nitrophenyl-alpha-D-maltotrioside(CNP-G3) as substrate.Methods: The studies were respectively carried out by measuring the velocity of enzyme-promoting reaction.Results: There were calcium and ammonium with a weak activation for α-amylase in cation. Chloride had a strong activation for the enzyme that was about four times as strong as sodium azide in anion. Acetate radical ion had a weak stimulated effect and sulfate, phosphate and carbonate radical ions had no any activation. Ethylenediaminetetraacetic acid(EDTA) was a powerful inhibitor of α-amylase. The optimum pH of the enzyme was from 5.9 to 6.1 and km value of α-amylase with CNP-G3 as substrate was about 0.22 mmol/L. Maltose had marked inhibitory action on amylase activity. As being calcium chelant, ethylene glycol-bis(-aminoethyl ether)N,N,N',N'-tetraacetic acid(EGTA) could regulate the reactive rate.Conclusion: The research on reactive system of α-amylase and CNP-G3 could be used to measure activity and agonist of the enzyme.

关 键 词：Α-淀粉酶 2-氯-4-硝基苯-麦芽三糖苷 激动剂 KM值 

分 类 号：R446.1[医药卫生—诊断学]