title: Proteolytic gut activities in the rice water weevil, Lissorhoptrus brevirostris Suffrian (Coleoptera: Curculionidae).
abstract: Digestive endoprotease activities of the rice water weevil, Lissorhoptrus brevirostris Suffrian (Coleoptera: Curculionidae), were characterized based on the ability of gut extracts to hydrolyze specific synthetic substrates, optimal pH, and hydrolysis sensitivity to protease inhibitors. Larvae of this species were found to use a complex proteolytic system that includes cathepsin D-, cathepsin B-, trypsin-, and chymotrypsin-like activities. Trypsin-like activity was evenly distributed among the anterior, middle, and posterior portions of the gut, whereas cathepsin B- and cathepsin D-like activities were mainly located in the anterior and middle sections, and the chymotrypsin-like activity was highest in the middle and posterior sections. Gelatin-containing native-PAGE gels indicated the presence of several aspartyl, cysteine, and serine protease forms and confirmed the spatial organization of the proteolytic digestive process.
authors.affiliation: Center for Genetic Engineering and Biotechnology, Sancti Spiritus, Cuba.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Hernández
authors.forename: Merardo
authors.initials: M
authors.lastname: Pujol
authors.forename: Julio
authors.initials: J
authors.lastname: Alfonso-Rubí
authors.forename: Raúl
authors.initials: R
authors.lastname: Armas
authors.forename: Yamilet
authors.initials: Y
authors.lastname: Coll
authors.forename: Maylin
authors.initials: M
authors.lastname: Pérez
authors.forename: Annerys
authors.initials: A
authors.lastname: González
authors.forename: Marisa
authors.initials: M
authors.lastname: Ruiz
authors.forename: Pedro
authors.initials: P
authors.lastname: Castañera
authors.forename: Félix
authors.initials: F
authors.lastname: Ortego
mesh_terms: D000818:Animals; D001517:Coleoptera / Q000201:enzymology*; D003545:Cysteine / Q000494:pharmacology; D004064:Digestive System / Q000033:anatomy & histology / Q000201:enzymology*; D004229:Dithiothreitol / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D010450:Endopeptidases / Q000378:metabolism*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007814:Larva; D011480:Protease Inhibitors / Q000494:pharmacology; D013379:Substrate Specificity
chemical_list: D004791:Enzyme Inhibitors; D011480:Protease Inhibitors; D010450:Endopeptidases; D003545:Cysteine; D004229:Dithiothreitol