摘要
研究了金属离子对棉铃虫N-乙酰--βD-氨基葡萄糖苷酶(EC3.2.1.52)活力的影响.结果表明:Na+、K+和Li+等金属离子对酶活力没有任何影响;在指定范围内,Mg2+和Ca2+对酶活力影响不显著;Zn2+、Cu2+和Al3+对该酶有不同程度的抑制作用.进一步研究Cu2+和Al3+的抑制作用动力学,结果表明:Cu2+对该酶的抑制作用是一种可逆过程,抑制机理表现为混合型,抑制常数KI为0.23 mmol/L,KIS为1.49 mmol/L.Al3+对该酶的抑制作用是一种可逆过程,抑制机理表现为竞争性类型,抑制常数KI为6.42 mmol/L.
The effects of metal ions on β-N-acetyl-D-glucosaminidase (NAGase, EC3. 2.1. 52) from Helicoverpa armigera have been studied. The results show that Na^+ , K^+ and Li^+ ions have no effect on the enzyme activity. Mg^2+ and Ca^2+ ions have few effects on the enzyme activity,while Zn^2+ ,Cu^2+ and Al^3+ inhibit the enzyme. The inhibitory kinetics of Cu^2+ and Al^3+ on the enzyme was further studied. The results showed that Cu^2+ was a reversible inhibitor of the enzyme and the inhibition was determined to be of mixed type. The inhibition constants of free enzyme (Kl) and enzyme-substrate complex (K1s) are determined to be 0. 23 mmol/L and 1.49 mmol/L, respectively. Al^3+ is a reversible competitive inhibitor of the enzyme, and the inhibition constants (Kl) was determined to be 6.42 mmol/L.
出处
《厦门大学学报(自然科学版)》
CAS
CSCD
北大核心
2005年第6期843-846,共4页
Journal of Xiamen University:Natural Science
基金
福建省科技攻关课题(2004N002)
福建省自然科学基金(B0410003)资助