以水解试验为导向,采用硫酸铵分级沉淀、Sephadex G-100凝胶层析、DEAE-DE52阴离子交换柱层析等手段分离纯化南美白对虾虾头主要自溶酶,同时采用抑制剂试验及SDS-PAGE对纯化蛋白酶进行鉴定。结果表明,南美白对虾虾头主要自溶酶经过纯化后比活力高达2.2×106U/g,纯化倍数为96.90。丝氨酸蛋白酶抑制剂苯甲基磺酰氟(PMSF)对主要自溶酶的抑制率高达91.3%;SDS-PAGE显示该酶为单一电泳带,且在电泳中与标准胰蛋白酶移动距离相同,表明南美白对虾虾头内的主要自溶酶为胰蛋白酶。

With hydrolysis test as an orientation,the major autoenzyme was purified from the head of white shrimp(Penaeus vannamei) by sulfate precipitation,gel filtration on Sephadex G-100 followed by ion-exchange chromatography DEAE-DE52.The autoenzyme was then identified by inhibitor tests and SDS-PAGE analysis.The results showed the major autoenzyme from the head of white shrimp had a specific activity of 2.2×106 U/g with a 96.90-fold increase over that of the crude enzyme extract.This autoenzyme was inhibited by serine protease inhibitor phenyl methyl sulfonyl fluoride(PMSF) with the inhibition rate being 91.3%,and illustrated as a single band in SDS-PAGE with the same distance as that of standard trypsin.These results indicated that trypsin was the major autoenzyme in the head of white shrimp.