Study on Structure and function of enterotoxins

1)分离纯化了三种Vero毒素VT1、VT2和VT2vh，并对其理化性质进行了研究；2)测定了VT1、VT2和VT2vh的核苷酸序列；3)发现VT1、VT2和VT2vh的作用方式与志贺毒素和蓖麻毒素相同。4)测定了产肠毒素大肠杆菌产生的热稳定型肠毒素的3个二硫键位点，发现这3个二硫键对毒素的生物活性起重要作用。

1) Three KInds of Vero toxins (VT1,VT2 and VT2vh) were purified and their physicochemical properties were studied 2) Nucleotide sequences of VT1, VT2 and VT2vh were determined 3) Mode of action of VT1, VT2 and VT2vh was found to be identical to that of Shiga toxin and ricin. These toxins showed RNA N-glycosidase activity and this resulted in the inhibition of protein synthesis in enkaryotic cells 4) The sites of three disulfide bonds of heat-stable enterotoxins produced in by enterotoxigenic Escherichie coli were determined and it was found that these three disulfide bonds were important for the biological activity of the toxin.