Protease inhibitors from Ecballium elaterium seeds

Int J Pept Protein Res. 1989 Mar;33(3):202-8. doi: 10.1111/j.1399-3011.1989.tb00210.x.


Several protease inhibitors were found in the seeds of a Cucurbitacea, Ecballium elaterium, and were separated from one another by affinity and molecular sieve chromatography. Three main trypsin isoinhibitors were purified by ion-exchange chromatography and the sequence of the major one, EETI II, was elucidated and compared with other inhibitors of the squash family. It is a peptide of M.W. 3020 of strong inhibitory activity (Ka = 8 x 10(11) M-1) against trypsin, showing high Gly content, six half-cystine residues, but devoid of histidine, threonine, tryptophan, and tyrosine residues.

MeSH terms

  • Amino Acid Sequence
  • Chymotrypsin / antagonists & inhibitors
  • Molecular Sequence Data
  • Molecular Weight
  • Pancreatic Elastase / antagonists & inhibitors
  • Protease Inhibitors / isolation & purification*
  • Seeds / analysis*
  • Subtilisins / antagonists & inhibitors
  • Trypsin Inhibitors / isolation & purification


  • Protease Inhibitors
  • Trypsin Inhibitors
  • Subtilisins
  • Chymotrypsin
  • Pancreatic Elastase