人纤维蛋白溶酶原中色氨酸残基的化学修饰

Chemical Modification of Tryptophan Residues in Human Plasminogen

以N－溴代琥珀酰亚胺为修饰剂，对人纤维蛋白溶酶原（HPg）中色氨酸（Trp）残基的分布及其与酶活力的关系进行了研究，发现每个HPg分子有19个Trp残基，5个位于分子表面；有2个是快反应残基，其中1个是活性必需的氨基酸．酶被修饰后其荧光光谱及圆二色谱发生了变化．

Tryptophan(Trp) residues in human plasminogen(HPg) was modified by N-bro-mossuccinimide(NBS). The results indicate that there are 19 tryptophan residues in HPg.Five tryptophan residues are located on the surface of the enzymogen, two of them are fast reactive residues. Among all the Trp residues, one is essential for the activity of the enzyme and may be located at the substrate binding site of the enzyme. The spectra of circular dichroism(CD) of HPg are changed after treatment with NBS.