【摘要】 研究了巯基乙酸对黑曲霉过氧化氢酶的激活作用 ,并从动力学和谱学角度研究了其激活原因 .过氧化氢酶被巯基乙酸激活后 ,其km 值减小、kcat/km 增大 ,即巯基乙酸能够提高过氧化氢酶对底物的亲和力及底物专一性 .巯基乙酸同样能够引起过氧化氢酶的可见光谱的蓝移及酶分子的色氨酸残基的荧光强度减小 ,从而使过氧化氢酶活性中心铁卟啉周围环境发生变化 ,以达到提高酶活力之目的更多还原

【Abstract】 The activation of catalase from Aspergillus niger by thioglycolic acid was investigated. Thioglycolic acid showed positive effect on catalase activity and the optimal concentration of thioglycolic acid was 0.6 mmol/L. The reasons of the activation of thioglycolic acid were also investigated by the determination of kinetic constants, the absorbance and emission fluorescence. The kinetic parameters, indicated that the addition of thioglycolic acid enhanced the affinity and specificity of catalase. The heme environment (active site) and tryptophane resides of catalase were altered by thioglycolic acid.更多还原