title: Cathepsin B-like activity predominates over cathepsin L-like activity in adult Schistosoma mansoni and S. japonicum.
abstract: Both cathepsin B-like and cathepsin L-like endopeptidase activities have been described in schistosomes, but their relative contribution to proteinolysis remains controversial. In an attempt to clarify which type of activity predominates, the selective mammalian cathepsin B inhibitor CA-074 was tested under standardized assay conditions with different preparations from Schistosoma mansoni and S. japonicum. CA-074 (0.94 microM) inhibited at least 92% and 80% of proteinolytic activity, respectively, for these species: completely inhibited bovine-spleen cathepsin B activity; but showed only marginal inhibition (4%) of rat-liver cathepsin L activity. We discuss the results with respect to previous studies and conclude that schistosome cathepsin B-like, not L-like, activity predominates.
authors.affiliation: Institut für Tropenhygiene, Heidelberg, Germany.
authors.forename: C R
authors.initials: CR
authors.lastname: Caffrey
authors.forename: A
authors.initials: A
authors.lastname: Ruppel
mesh_terms: D000818:Animals; D002401:Cathepsin B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D056668:Cathepsin L; D002403:Cathepsins / Q000378:metabolism*; D003546:Cysteine Endopeptidases; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004151:Dipeptides / Q000494:pharmacology; D010450:Endopeptidases; D012549:Schistosoma japonicum / Q000201:enzymology*; D012550:Schistosoma mansoni / Q000201:enzymology*
chemical_list: D015853:Cysteine Proteinase Inhibitors; D004151:Dipeptides; C068250:N-(3-propylcarbamoyloxirane-2-carbonyl)-isoleucyl-proline; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; D056668:Cathepsin L; C534280:Ctsl protein, rat