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从假菠萝麻叶汁中用乙醇分部沉淀法得到一种蛋白酶，对酪蛋白有强烈的水解活性。经ＳｅｐｈａｄｅｘＧ－１００柱层析和ＳＰ－ＳｅｐｈａｄｅｘＣ－５０离子交换柱层析等步骤纯化，可得到六角形结晶。结晶酶液经ＰＡＧＥ圆盘电泳，每条胶柱上只显示一条蛋白带。其活性在ｐＨ４．５～１０、５５℃范围内较稳定，最适ｐＨ８．５，最适温度５０℃，Ｋｍ（酪蛋白）值为０．１８５％（Ｗ／Ｖ）。用ＳＤＳＰＡＧＥ和ＳｅｐｈａｄｅｘＧ－１００测得其分子量分别为８８１００和８５１００。用ＰＡＧＥ等电聚焦电泳测得其ｐＩ值为７．９。该酶活性受到Ｃｙｓ、ＥＤＴＡ的激活；受到ＩＣＨ２ＣＯＯＨ、ＨｇＣｌ２、ＤＴＮＢ的抑制，说明该酶是一种巯基蛋白酶，用Ｅｌｌｍａｎ’ｓ试剂测得每个酶分子含有４个游离巯基．暂定名为假菠萝麻蛋白酶。
From fake pineapple leaf juice ethanol fraction precipitation obtained a protease, casein has a strong hydrolytic activity. After purification by SephadexG-100 column chromatography and SP-Sephadex C-50 ion exchange column chromatography, hexagonal crystals can be obtained. Crystallized enzyme gel electrophoresis PAGE, each gel column only shows a protein band. The activity was stable at pH4.5 ~ 10,55 ℃, the optimum pH was8.5, the optimum temperature was50 ℃ and the Km (casein) was0.18% (W / V). Their molecular weights were 88100 and 85100, respectively, measured by SDSPAGE and SephadexG-100. The pI value was 7.9 by PAGE isoelectric focusing. The enzyme activity is activated by Cys, EDTA; by ICH2COOH, HgCl2, DTNB inhibition, indicating that the enzyme is a sulfhydryl protease, Ellman’s reagent contains four free thiol per enzyme molecule. Tentatively named fake pineapple hemp enzyme.