黑豆种子中一种耐热型胰蛋白酶抑制剂的分离及性质表征

应用硫酸铵分级沉降、弱阳交换色谱CM-Sephadex C-50、凝胶过滤 色谱Sephacryl S-200HR、强阳离子高效液相色谱POROS HS-20，从黑豆种 子中分离纯化一种耐热型蛋白酶抑制剂，命名为TSTI.该蛋白的Ｎ末端序列 为DEYSKPCCDLCMCTRRCPPQ，与豆科植物Bowman-Birk型胰蛋白酶抑制剂具有 高度同源性，推测其属于Bowman-Birk型胰蛋白酶抑制剂.SDS－PAGE和IEF 测出TSTI分子量和等电点分别为23.9 kD 和6.2.TSTI对胰蛋白酶有很强的 抑制作用，当二者摩尔比达到1时，胰蛋白酶活力被完全抑制.此外，该蛋 白酶抑制剂具有很强的热稳定性和pH稳定性，在高达100 ℃温度及pH2-12 范围内处理，其活性均不会受到太大影响.TSTI对植物致病菌苹果轮纹病菌 、瓜果腐霉病菌、白菜黑斑病菌、甜瓜枯萎病菌和葡萄灰霉病菌具有抑制 作用.

Isolation and Characterization of a Thermostable Trypsin Inhibitor from Black Soybean

A thermostable trypsin inhibitor,designated TSTI(thermostable trypsin inhibitor),was isolated from seeds of black soybean(Glycine max L.merr).The purification steps involved ammonium sulfate precipitation,ion-exchange chromatography on CM-Sephadex C-50,gel filtration chromatography on Sephacryl S-200HR and HPLC on POROS HS-20.Its N-terminal amino acid sequence was DEYSKPCCDLCMCTRRCPPQ,which exerted highly homologies with the sequence of Bowman-Birk type trypsin inhibitors.It was speculated that TSTI should ...