乌鳢鱼卵中胰蛋白酶抑制剂的分离纯化及性质研究

摘要

A protein with an apparent molecular weight of 42 kDa was purified from the egg of Snakehead （Ophi-cephalas argus） by gel filtration chromatography. The purified protein showed that a trypsin inhibitor activity with minimal critical concentration of inhibition was 130 μg/mL and potently inhibited trypsin with a Ki value of 30.3 nM. The research on its physics and chemistry nature indicates that the proteinase inhibitor has a very strong sup- pressing activeness to serine proteinase as well as a long-time thermal stability and an acid and alkali stability.%以乌鳢鱼卵为材料，通过生物化学手段和研究方法，从乌鳢鱼卵匀浆液中分离得到了一种相对分子质量大约为42kDa的蛋白酶抑制剂．该蛋白对胰蛋白酶具有专一性的抑制活性，最低抑制浓度为130μg／mL，对胰蛋白酶的抑制常数为30．3nM．SDS—PAGE电泳检测表明，该抑制剂为不合二硫键的单链蛋白．热稳定性和酸碱稳定性研究表明，该蛋白酶抑制剂在30℃～100℃温度下能保持76％以上的活性，在pH值2～11的酸碱条件下，能保持90％以上的活性。