title: Serine protease activities in Oxysarcodexia thornax (Walker) (Diptera: Sarcophagidae) first instar larva.
abstract: We report for the first time the expression of multiple protease activities in the first instar larva (L1) of the flesh fly Oxysarcodexia thornax (Walker). Zymographic analysis of homogenates from freshly obtained L1 revealed a complex proteolytic profile ranging from 21.5 to 136 kDa. Although some activities were detected at pH 3.5 and 5.5, the optimum pH for most of the proteolytic activities was between pH 7.5 and 9.5. Seven of 10 proteases were completely inactivated by phenyl-methyl sulfonyl-fluoride, suggesting that main proteases expressed by L1 belong to serine proteases class. Complete inactivation of all enzymatic activities was obtained using N-p-Tosyl-L-phenylalanine chloromethyl ketone (100 microM), a specific inhibitor of chymotrypsin-like serine proteases.
authors.affiliation: Laboratório de Pesquisas em Leishmanioses, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brasil.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Cuervo
authors.forename: Camila
authors.initials: C
authors.lastname: Mesquita-Rodrigues
authors.forename: Claudia Masini
authors.initials: CM
authors.lastname: d'Avila Levy
authors.forename: Constança
authors.initials: C
authors.lastname: Britto
authors.forename: Fabiano Araújo
authors.initials: FA
authors.lastname: Pires
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Gredilha
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Alves
authors.forename: Jose Batista de
authors.initials: JB
authors.lastname: Jesus
mesh_terms: D000818:Animals; D004175:Diptera / Q000201:enzymology* / Q000254:growth & development; D004591:Electrophoresis, Polyacrylamide Gel; D007814:Larva / Q000201:enzymology; D012697:Serine Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D012697:Serine Endopeptidases