title: Schistosoma japonicum, S. mansoni, S. haematobium, S. intercalatum, and S. rodhaini: cysteine-class cathepsin activities in the vomitus of adult worms.
abstract: Vomitus from adults of five Schistosoma species was screened for biochemical homologues of the mammalian cysteine proteinases cathepsins B, H, and L. Bovine cathepsin B and rat cathepsin L served as references. Using the substrate Arg-NMec, a schistosome cathepsin H-like activity was never detected. All species degraded the cathepsin B substrate Z-Arg-Arg-NMec, but distinct species differences were observed with respect to pH optima and buffer preferences. The cathepsin B and L substrate Z-Phe-Arg-NMec was similarly degraded by all species, and activity was abolished by the cysteine proteinase inhibitor E-64. Preferences by vomitus proteinase activities for Z-Phe-Arg-NMec over Z-Arg-Arg-NMec were similar to or higher than those found for bovine cathepsin B but well below those observed for rat cathepsin L; also, the preferential cathepsin L inhibitor Z-Phe-PheCHN2 only partially inhibited proteinolytic activity. The results suggest the possible presence in vomitus of a minor cathepsin L-like activity and demonstrate a major cathepsin B-like activity that is biochemically variable between schistosome species.
authors.affiliation: Institut für Tropenhygiene, Universität Heidelberg, Germany.
authors.forename: C R
authors.initials: CR
authors.lastname: Caffrey
authors.forename: C E
authors.initials: CE
authors.lastname: Rheinberg
authors.forename: H
authors.initials: H
authors.lastname: Moné
authors.forename: J
authors.initials: J
authors.lastname: Jourdane
authors.forename: Y L
authors.initials: YL
authors.lastname: Li
authors.forename: A
authors.initials: A
authors.lastname: Ruppel
mesh_terms: D000818:Animals; D002401:Cathepsin B / Q000378:metabolism; D056655:Cathepsin H; D056668:Cathepsin L; D002403:Cathepsins / Q000378:metabolism*; D003546:Cysteine Endopeptidases / Q000187:drug effects / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D010450:Endopeptidases; D005766:Gastrointestinal Contents / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D012547:Schistosoma / Q000201:enzymology*; D012548:Schistosoma haematobium / Q000201:enzymology; D012549:Schistosoma japonicum / Q000201:enzymology; D012550:Schistosoma mansoni / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D015853:Cysteine Proteinase Inhibitors; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; D056668:Cathepsin L; C534280:Ctsl protein, rat; D056655:Cathepsin H; C534128:Ctsh protein, rat