First report on a potato I family chymotrypsin inhibitor from the seeds of a Cucurbitaceous plant, Momordica cochinchinensis

Biol Chem. 2004 Feb;385(2):185-9. doi: 10.1515/BC.2004.037.

Abstract

A 7514-Da chymotrypsin inhibitor was isolated from the seed extract of Momordica cochinchinensis (Family Cucurbitaceae) by chromatography on chymotrypsin-Sepharose 4B and subsequently by C18 reversed-phase HPLC. This inhibitor, named MCoCl, possessed remarkable thermostability and was stable from pH 2 to 12. MCoCl also inhibited subtilisin, but had at least 50-fold lower inhibitory activity towards trypsin and elastase. Amino acid sequencing of a peptide fragment of MCoCl revealed a sequence of 23 amino acids. Comparison of this sequence and the molecular mass with those of other protease inhibitors suggests that MCoCl belongs to the potato I inhibitor family.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Chromatography, Affinity
  • Chromatography, High Pressure Liquid / methods
  • Chymotrypsin / antagonists & inhibitors*
  • Molecular Sequence Data
  • Molecular Weight
  • Momordica / enzymology*
  • Pancreatic Elastase / antagonists & inhibitors
  • Peptide Fragments / genetics
  • Seeds / enzymology*
  • Sequence Alignment
  • Serine Proteinase Inhibitors / chemistry*
  • Serine Proteinase Inhibitors / genetics
  • Serine Proteinase Inhibitors / isolation & purification
  • Serine Proteinase Inhibitors / pharmacology*
  • Solanum tuberosum / enzymology
  • Subtilisins / antagonists & inhibitors
  • Trypsin / metabolism

Substances

  • Peptide Fragments
  • Serine Proteinase Inhibitors
  • Subtilisins
  • Chymotrypsin
  • Pancreatic Elastase
  • Trypsin