title: [Studies on cathepsins in Schistosoma japonicum].
abstract: OBJECTIVE
  To identify the cathepsins in adult worms of Schistosoma japonicum and their proteolytic activities.
  
  
  METHODS
  The vomitus from adult worms of S. japonicum was collected. The proteolytic activity of cathepsins in the vomitus was identified and measured using synthetic substrates with arginyl bonds.
  
  
  RESULTS
  Specific synthetic subtracts Z-Arg-Arg-AMC (for cathepsin B) and Z-Phe-Arg-AMC (for cathepsin B and L) were degraded by the vomitus. An inhibitor, Z-Phe-PheCHN2 for cathepsin L, inhibited partially the activity of the vomitus to degrade Z-Phe-Arg-AMC. The optimal pH for cathepsin B/L is 5.0-5.5.
  
  
  CONCLUSIONS
  The vomitus of S. japonicum has cathepsin B- and L-like activity.
authors.affiliation: Department of Parasitology, Tongji Medical University, Wuhan 430030.
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: Y
authors.initials: Y
authors.lastname: Fen
authors.forename: C
authors.initials: C
authors.lastname: Caffrey
authors.forename: A
authors.initials: A
authors.lastname: Ruppel
mesh_terms: D000818:Animals; D002403:Cathepsins / Q000032:analysis*; D012549:Schistosoma japonicum / Q000201:enzymology*
chemical_list: D002403:Cathepsins