title: Proteolytic enzymes of infective larvae and adults of Trichostrongylus colubriformis and Haemonchus contortus.
abstract: The aim of this study was to acquire preliminary characterisation of the proteolytic enzymes of Trichostrongylus colubriformis and Haemonchus contortus so as to obtain a better understanding of the parasites' defence mechanisms against the host immune response. The proteinase band-pattern activity obtained using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed nine bands in T. colubriformis and H. contortus L3 larvae and four bands in adult T. colubriformis at alkaline pH. Similar testing of adult H. contortus at acidic pH gave four bands. Within the same species the same proteinase may occur in both larvae and adults. Some enzymes of similar molecular weight occurred in both species, but their relative activities differed. The majority of proteinases of T. colubriformis and H. contortus larvae and adult forms are generally of high molecular weight (35-200 kDa). Because proteinase of T. colubriformis and H. contortus have been difficult to classify on the basis of their enzymatic activity, we suggest they may be proteasomes.
authors.affiliation: AgResearch, Wallaceville Animal Research Centre, Upper Hutt, New Zealand.
authors.forename: E
authors.initials: E
authors.lastname: Hadas
authors.forename: M
authors.initials: M
authors.lastname: Stankiewicz
mesh_terms: D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases / Q000302:isolation & purification* / Q000378:metabolism; D006189:Haemonchus / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007814:Larva / Q000201:enzymology; D011480:Protease Inhibitors / Q000494:pharmacology; D012756:Sheep; D014252:Trichostrongyloidiasis / Q000276:immunology; D014254:Trichostrongylus / Q000201:enzymology*
chemical_list: D011480:Protease Inhibitors; D010450:Endopeptidases