摘要 |
<p>A synthetic polypeptide having at least about 10% of the immunological activity of biologic heat-stable enterotoxin of E. coli. The synthetic polypeptide includes at least 14 amino acids in the sequence, from amino-terminus to carboxy-terminus, represented by the formula: CysCysGluLeuCysCysTyr(Asn)ProAlaCysAla(Thr)GlyCysAsn(Tyr) wherein the amino acid in parentheses may replace the immediately preceding amino acid residue, and at least one intramolecular disulfide bond formed between the Cys residues. The Cys residues that are not part of the intramolecular disulfide bond can be replaced by other amino acid residues or be bonded to substituent moieties. The polypeptides can be a monomeric or multimeric material containing an intramolecular, intrapolypeptide and/or an intramolecular, interpolypeptide cystine disulfide bond.</p> |