Development of an ELISA Kit to detect ST produced by enterotoxigenic Esherichia coli by using chemically synthesized antigens.

1)建立了检测产肠毒素大肠杆菌ST的竞争ELISA方法。一种化学合成的STh类似物，它与硼血清白蛋白缀合用作固相。作为抗体，有两种。2）建立的竞争性ELISA检测方法，成功地检测了200株标准大肠杆菌产生的ST。大肠杆菌菌株和约1700株E. 3）测定了ST的二硫键模式; 4）应用建立的ELISA方法研究了ST的构效关系

1) A competitive ELISA system to detect ST produced by enterotoxigenic Escherichia coli was developed. A chemically synthesized STh analogue that was conjugated with borine serum albumin was used as the solid phase. As the antibody, two kinds. of monoclonal antibodies each of which recognized different epitopes of STh were used and they were conjugated with horse raddish peroxidase.2) The developed competitive ELISA sucessfully detected ST produced by about 200 standard E. coli strains and about 1700 strains of E. coli isolated from patients of traveller's diarrhoea.3) Mode of disulfide linkages of ST was determined.4) The developed ELISA was applied to study the structure-activity relationship of ST