大肠杆菌热敏感肠毒素的检测与制备

Detection and Preparation of the Heat-labile Enterotoxin of E.coli

为探索猪源大肠杆菌热敏感肠毒素的简易检测方法和纯化方法,拟采用兔回肠结扎试验、兔皮肤蓝斑试验和平板免疫溶血试验比较检测热敏感肠毒素的方法。初步试验表明:平板免疫溶血试验能够快速灵敏地检测出热敏感肠毒素,并具有很强的特异性,比肠结扎试验灵敏度高,而且简便易行;采用SephadexG 100纯化热敏感肠毒素LT并采用SDS PAGE电泳检测蛋白纯度,表明该方法可以除去杂蛋白,肠毒素蛋白分子量为12

The heat-labile enterotoxin of porcine E.coli isolates was assayed by ligation of rabbit ileum (LRI), plate immune hemolysis assay (PIHA) and blue spot in rabbit skin (BSRS), the positive result rate by PIHA and LRI was higher than that by BSRS. The heat-labile enterotoxin was purified by Sephadex G-100 column chromatography and identified by PIHA. After dialyzed against water, the sediment was analyzed by SDS-PAGE and the molecular weights of the protein were 12.5 KD and 25 KD.