【摘要】 荞麦胰蛋白酶抑制剂(BuckwheatTrypsinInhibitor,BTI)是存在于荞麦种子中的一种抗营养因子。本文经过原核表达及两步层析纯化得到高纯度的重组荞麦胰蛋白酶抑制剂rBTI。通过分析表明,重组荞麦胰蛋白酶抑制剂与天然荞麦胰蛋白酶抑制剂的性质类似。rBTI的相对分子质量约为11kDa,等电点约为6.2。rBTI对胰蛋白酶有较强的抑制作用,抑制摩尔比(以BApNA为底物)为1:1.5。rBTI的最适pH值为8.0,在pH3.0～8.0之间有较好的热稳定性,100℃加热120min仍保持70%的胰蛋白酶抑制活性。更多还原

【Abstract】 Recombinant buckwheat trypsin inhibitor(rBTI)was purified by affinity chromatography on Ni2+-NTA column and gel filtration chromatography on Superdex G-75 10/30 HR.The analysis of some properties showed that rBTI was similar to the native trypsin inhibitors in buckwheat seeds.It has an approximate molecular mass of 11kDa,a pI of 6.2 and a pH optimum of 8.0.rBTI has a strong inhibition on trypsin with the mole ratio about 1:1.5.The protein possesses thermostability in the pH range 3.0～8.0.Even after 120min of heat treatment(100℃)the inhibitor still keeps over 70% of its trypsin inhibitory activity.更多还原