【摘要】 从厦门文昌鱼(Branchiostonia belcheri Gary)分离纯化获得聚丙烯酰胺胶电泳单一蛋白区带的酸性磷酸酯酶(EC3.1,3.2)应用化学修饰方法,荧光以及紫外-可见光谱的变化,探讨Trp残基与酶活力的关系,被NBS修饰的Trp基团仅有一个Trp残基被氧化时,酶活力丧失90％,该Trp残基为ACPase表现活力所必需,而且优先被氧化、从光谱扫描(230～600nm)结果表明,经NBS修饰以后的酶构象发生变化,文昌鱼ACPase的Trp残基和酶分子上的铁离子等基团均为酶活力的必需基团,推测两者可能以配位结合,共同维持酶活力中心的构象。更多还原

【Abstract】 The chemical modification of the ACPase from Branchiostoma belcheri by NBS, oxidation of 1 mol of Trp in ACPase required 5. 62 mol of NBS. There was about 90% loss of enzyme activity when only one tryptophan residue was oxidized. It was Shown that tryptophan residues relates to the enzyme activity, and one of the four tryptophan residues is essential to the enzyme activity. In the presence of NBS by means of fluorescence and UV-visible spectra, the changes in enzyme conformation and catalytic activity, results suggested that the tryptophan residue in the active site of ACPase更多还原