食品科学2017，Vol.38Issue(24)：28-33,6.DOI:10.7506/spkx1002-6630-201724005
鱿鱼肝脏蛋白酶的鉴定及组织蛋白酶L的分离纯化
Identification of Proteases and Purification of Cathepsin L from Squid Liver
摘要
Abstract
In order to understand the applicability of endogenous proteases from squid liver as a rich source of proteases, the endogenous proteases of squid liver were identified and characterized with common carp myofibrillar protein as substrate by adding a variety of protease inhibitors. It was found that the degradation of myosin heavy chain (MHC) was significantly inhibited by addition of E-64, 1,10-phenanthroline and PMSF to the reaction system indicating that squid liver contained three kinds of proteases, metalloprotease, cysteine protease and serine protease. The cysteine protease had the best thermal stability and highest activity, which still maintained a high activity at temperatures higher than 50 ℃, and it could hydrolyze myofibrillar proteins into small molecules. Substrate specificity analysis indicated that the cysteine protease could only hydrolyze Z-phe-Arg-MCA, and was inhibited 100% by leupeptin and 99.4% by E-64, indicating that the enzyme consisted mainly of cathepsin L. At last, cathepsin L was purified to homogeneity by ammonium sulfate precipitation, ion exchange and gel filtration chromatography. The purified enzyme showed a molecular weight of about 25 kD.关键词
鱿鱼肝脏/酶解/抑制剂/荧光底物/组织蛋白酶LKey words
squid liver/enzymatic hydrolysis/inhibitor/fluorogenic substrate/cathepsin L分类
轻工纺织引用本文复制引用
田元勇,宋扬,郑尧,刘慧慧,刘俊荣..鱿鱼肝脏蛋白酶的鉴定及组织蛋白酶L的分离纯化[J].食品科学,2017,38(24):28-33,6.基金项目
国家自然科学基金面上项目(31671790) （31671790）
辽宁省教育厅科学研究一般项目(L2015082) （L2015082）
教育部留学回国人员科研启动基金项目(教外司留[2013]693号) （教外司留[2013]693号）
