摘要
以黄粉虫为材料,以N-乙酰--βD-氨基葡萄糖苷酶(NAGase,EC 3.2.1.52)为研究对象.研究各种金属离子对NAGase酶活力的影响.结果表明,正一价碱金属Li+、Na+、K+等对酶活力基本上没有效应;Ca2+、Mg2+、Ba2+等碱土金属离子对酶活力也没有显著影响;而正三价金属离子Al3+和Fe3+、过渡金属离子Zn2+和Cd2+、重金属离子Cu2+、Ag+、Hg2+和Pb2+等对该酶活力均有不同程度的抑制作用.其中,Hg2+的抑制作用最为显著,2.5 mmol/L Hg2+可使酶活力完全丧失.进一步研究了Cu2+的抑制作用动力学,结果显示:Cu2+对酶的抑制作用为非竞争性可逆抑制,抑制常数KI=KIS=5.5 mmol/L.
N-acetyl-β-D-glucosaminidase （NAGase,EC 3.2.1.30） from Tenebrio molitor Linneeus is obtained by extraction and ammonium sulfate fractionation. The effects of metal ions on the enzyme activity are surveyed. The alkali metals ions such as Li^＋ ,Na^＋ and K^＋ has no any effects on the enzyme activity. The alkaline earth metals ions such as Ca^2＋ , Mg^2＋ , Ba^2＋ had also no abvious effect on the enzyme. While Al^3＋ ,Fe^3＋ ,Zn^2＋ ,Cd^2＋ ,Hg^2＋ ,Ag^＋ ,Pb^2＋ and Cu^2＋ inhibits the enzyme activity to some extent. The inhibitory effect of Hg^2＋ is the most potent, 2. 5 mmol/L of Hg^2＋ leads to the enzyme completely inactive. The inhibitory kinetics of Cu^2＋ on the enzyme is further studied. The result shows that Cu^2＋ is a reversible uncompetitive inhibitor of the enzyme, and the inhibition constants （KI and KIS） is determined to be at a level of 5.5 mmol/L.
出处
《泉州师范学院学报》
2007年第2期113-117,共5页
Journal of Quanzhou Normal University
作者简介
潘小芳（1958-），女，福建永春人，实验师，从事无机化学、生物化学研究．
