【摘要】 基于乳酸脱氢酶(LDH)催化乳酸和氧化型烟酰胺腺嘌呤二核苷酸(NAD)的反应,在最佳酶反应条件下,研究了金属离子对酶催化的抑制作用.发现Zn2+对LDH的酶促反应有显著的抑制,抑制常数KQS为13mmol/L,属非竞争性抑制.根据在抑制剂作用下的米氏方程,可以利用酶法对锌离子进行定量测定.通过加入金属离子络合剂乙二胺四乙酸(EDTA)进行了干扰消除实验,结果表明:可有效消除一定浓度的Zn2+对LDH酶促反应测定底物的干扰.更多还原

【Abstract】 The inhibition of zinc(Ⅱ) to the enzymatic reaction under the optimum conditions based on the catalytic reaction of lactic acid and nicotinamide adenine dinucleotide oxidized form(NAD) by lactate dehydrogenase(LDH) was studied.That enzymatic reactions were inhibited obviously by Zn2+ was discovered.The inhibition constant(KQS) of Zn2+ is 13mmol/L.The inhibition is non-competitive type,according to the MichaelisMenten equation at the presence of inhibitors,zinc(Ⅱ) can be determined by the enzymatic method.The experiment of the elimination of interference was affected by adding the ligand of metal ions-ethylene diamine tetraacetic acid(EDTA).The result indicates that interference of certain concentration’s Zn2+ for determining substrates by the catalytic reaction of LDH can be eliminated effectively.更多还原