Análise bioquímica do produto de secreção/excreção de larvas de Cochliomyia hominivorax (Coquerel, 1858) (Diptera, Calliphoridae)

• Autor(a) principal: Teixeira, Denise Gonçalves
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000006cp6
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/5037
• topic: Díptero; Enzima; Parasitos; Mosca; Miíase; Diptera; Enzyme; parasites; Fly; Myiasis; MEDICINA VETERINARIA PREVENTIVA::SAUDE ANIMAL (PROGRAMAS SANITARIOS)

The species Cochliomyia hominivorax, popularly known as screwworm fly, is a Diptera belonging to the family Calliphoridae. Its larvae are obligated parasites of warm-blooded animals and its geographic range extends throughout Latin America. Some studies accomplished with flies that produce myiasis concluded that the production of digestive enzymes secreted and / or excreted by the larvae has crucial contribution to the establishment and survival of these parasites in the host. Due to the lack of information approaching this subject on C. hominivorax, this project aimed to characterize and classify the enzymes in the secretion and excretion (S/E) of the larva of this fly, analyzing its biochemical profile.A colony of this species was established in laboratory conditions in order to accomplish this study. The colony was established by obtaining third instar larvae (L3)on naturally infested animals, and from the cultivation of these was obtained first (L1), second (L2) and third (L3) larvae instars,. The profile of proteins of S/E was obtained by polyacrylamide gel electrophoresis and proteolytic activity was analyzed using gelatin, azocasein and Na-benzoyl-arginine-nitroanilide as substrate. In S/E of the three instars proteins were detected with an apparent molecular weight ranging between 116 and 20 kDa. In the azocasein assay, at different pH ranges, it was observed that the major proteolytic activity occurs at pH 7.5 for all larvaeinstars. For characterization of the enzyme, assays were performed using these same substrates in which the samples were treated with inhibitors Benzamidine, Pepstatin A, AEBSF, TLCK, TPCK, EDTA, leupeptin and E-64. Proteinases present in the E/S of L1 are mostly serine proteases trypsin and chymotrypsin, whereas for L2 and L3 the presence of serine proteases and aspartyl proteases were observed.