Purification and sequence of a presynaptic peptide toxin from Conus geographus venom

Biochemistry. 1984 Oct 23;23(22):5087-90. doi: 10.1021/bi00317a001.


A novel toxin, omega-conotoxin (omega-CgTX), from the venom of the fish-eating marine mollusc Conus geographus has been purified and biochemically characterized. Recently, this omega-conotoxin has been shown to inhibit the voltage-activated entry of Ca2+, thus providing a potentially powerful probe for exploring the vertebrate presynaptic terminal [Kerr, L. M., & Yoshikami, D. (1984) Nature (London) 308, 282-284]. The toxin is a basic 27 amino acid peptide amide with three disulfide bridges. An unusual feature is a remarkable preponderance of hydroxylated amino acids. The sequence of omega-CgTx GVIA is Cys-Lys-Ser- Hyp-Gly5-Ser-Ser-Cys-Ser-Hyp10-Thr-Ser-Tyr-Asn-Cys15-C ys-Arg-Ser- Cys-Asn20-Hyp-Tyr-Thr-Lys-Arg25-Cys-Tyr-NH2.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Amino Acids / analysis
  • Chromatography, Gel
  • Chromatography, High Pressure Liquid
  • Molecular Weight
  • Mollusk Venoms / analysis
  • Mollusk Venoms / isolation & purification*
  • omega-Conotoxin GVIA


  • Amino Acids
  • Mollusk Venoms
  • omega-Conotoxin GVIA