【摘要】 本文研究了不同浓度盐酸胍和脲溶液对猪肾氨基酰化酶活性和构象的影响。研究结果表明,在低浓度的胍和脲溶液中(小于2mol/L),酶分子的整体构象变化的程度与活力变化的程度基本是平行的;而在高浓度的胍和脲溶液中(2mol/L以上),失活程度稍大于构象变化的程度。这些结果与分子量和亚基组成基本相同,但不含金属配基的肌酸激酶的结果,以及小分子量的胰凝乳蛋白酶和牛胰核糖核酸酶的结果相比较来看,可以认为配基锌离子的存在对酶分子的活性部位区域构象的稳定作用有一定的贡献,致使氨基酰化酶的活性部位的构象状态不象后三种酶那样脆弱。同时,我们还发现锌离子的存在对酶分子整体构象的稳定性上贡献很小。更多还原

【Abstract】 The effects of different concentrations of guanidine and urea on the activity and conformation of pig kidney aminoacylase in solution have been studied. The results obtained clearly show that at low concentrations of guanidine and urea, less than 2m發/L, the degree of conformationsl changes in aminoacylase molecule is approximately in parallel to that of the disapperance of enzymatic activity, and at high concentrations of guanidine and urea, 2 mol/L or more, the degree of inactivation is more than that of the conformational changes of the enzyme. Comparing this result with those obtained from creatine kinase, chymotrypsin and ribonuclease, we suggest that Zn++ in aminoacylase molecule probably contributes partially to the stabilization of the local conformation in active sites of the protein, but has little effect on the overall conformation更多还原