黄鳝蛋白酶的化学修饰

采用NBS，BrAc，IAC，TNBS，PCMB，PMSF，2-ME7种化学修饰剂及Ca^2 ．Mg^2 ，Na^2 ，K^2 ，Cu^2 等9种金属离子和EDTA试剂对黄鳝蛋白酶进行处理，检测酶活性变化，以研究酶分子中氨基酸侧链基团与酶活性中心的关系。及金属离子和EDTA对酶活性的影响．实验结果表明；NBS．BrAe，IAC，TNBS，PMSF对酶的抑制作用很强，而PCMB，2-ME对酶活性影响不大。说明色氨酸残基、组氨酸残基、赖氨酸残基和丝氨酸残基的化学修饰对酶的活性影响很大。为酶活性的必需基团。而巯基、二硫键等与酶活性无直接关系．Cu^2 ，Ba^2 对酶的活性具有激活作用，Mg^2 ，Li 和K 对酶有轻微的抑制作用，而Pb^2 ，Mn^2 和EDTA对酶有很强的抑制作用，Ca^2 ，Na^2 对黄缮蛋白酶既无明显的激活作用，也无明显的抑制作用．

Chemical Modification of Protease from Monopterus Albus

The protease of Monopterus albus is a kind of alkaline protease. In order to investigate the relationship of the structure and function of protease, the effects of protein modification reagents, EDTA and metal ions on the protease activity from Monopterus albus have been studied. The enzyme activity was significantly decreased after modification of NBS, IAc, TNBS, BrAc and PMSF, but PCMB and 2-ME don't obviously effect enzyme activity. Cu~(2+), Ba~(2+) can activate the enzyme, Pb~(2+), Mn~(2+) and EDTA can strongly inhibit the enzyme activity, but Mg~(2+), Li~+ and K~+ only slightly, Ca~(2+)and Na~+have no effects on enzyme activity.