title: Bloodmeal digestion in the midgut of Phlebotomus papatasi and Phlebotomus langeroni.
abstract: Bloodmeal digestion in midguts of the sandflies Phlebotomus papatasi and Phlebotomus langeroni (Diptera: Psychodidae) was investigated in optimized assays to detect general protease, trypsin and aminopeptidase activities using synthetic substrates. Optimal activity occurred at pH 8-9 for all enzymes examined in both species. Protease activity peaked at 24-34 h post human bloodmeal in midguts of P. papatasi and 34-48 h in P. langeroni; all endo- and exoprotease activities were completed by 50 h in P. papatasi compared to 72 h in P. langeroni. Hydrolysis of two chymotrypsin substrates was < 2% of trypsin activity in both species. Aminopeptidase activity was associated mainly with the midgut wall, whereas trypsin activity was confined to the midgut lumen. A feature of digestion in P. langeroni was the high level of aminopeptidase recorded within 10 h of the bloodmeal.
authors.affiliation: Department of Medical Parasitology, London School of Hygiene and Tropical Medicine, UK.
authors.forename: R J
authors.initials: RJ
authors.lastname: Dillon
authors.forename: R P
authors.initials: RP
authors.lastname: Lane
mesh_terms: D000626:Aminopeptidases / Q000378:metabolism; D000818:Animals; D001769:Blood / Q000378:metabolism; D004063:Digestion / Q000502:physiology; D004064:Digestive System / Q000201:enzymology; D010450:Endopeptidases / Q000378:metabolism*; D005260:Female; D006863:Hydrogen-Ion Concentration; D010691:Phlebotomus / Q000201:enzymology* / Q000502:physiology; D011480:Protease Inhibitors / Q000494:pharmacology; D014325:Tromethamine; D014357:Trypsin / Q000378:metabolism
chemical_list: D011480:Protease Inhibitors; D014325:Tromethamine; D010450:Endopeptidases; D000626:Aminopeptidases; D014357:Trypsin