Synthesis and antigenic activity of E. coli ST and its analogues

Several enterotoxigenic E. coli (ETEC) are common causes of diarrhea in man and animals. These strains of E. coli produce two types of enterotoxins: heat-stable (ST) and heat-labile (LT). These toxins are peptides of molecular weight 2000 and 90,000 daltons, respectively. It is proposed that the synthetic analogues of these toxins could be effectively used as the vaccines against enterotoxigenic activity of E. coli. In this paper we report the isolation and chemical characterization of a heat-stable toxin STa. We also report the synthesis of this toxin and its analogues and their biochemical and immunological characterization.