Midgut Protease Activity During Larval Development of Anastrepha obliqua (Diptera: Tephritidae) Fed With Natural and Artificial Diet
Periodo de realización: 1900/01/01 al 2017/01/01
Tipo: Artículo científico
Lugar(es) de estudio: Tapachula, Chis., México
Resumen: "In this study, we examined the activity of two serine proteases (chymotrypsin and trypsin) and two metalloproteases
(carboxypeptidases A and B) during larval development in Anastrepha obliqua fed natural (mango fruit) and
artificial (formulation used in mass-rearing) diets. Proteolytic activity of chymotrypsin, trypsin, carboxypeptidase A,
and carboxypeptidase B was detected in the midgut of different instars of A. obliqua and was strongly affected by
the pH and diet type. The protein content of the natural and artificial diets was similar. Enzymatic activity was higher
in the midgut of the larvae fed the natural diet than in larvae fed the artificial diet. The activity of the endopeptidases
(chymotrypsin and trypsin) was lower than those of the exopeptidases (carboxypeptidases A and B). The pH of the
midgut varied from acidic to neutral. The results indicate that in the midgut of the larvae reared on both types of diet,
the level of carboxypeptidase activity was approximately 100-fold greater than the level of chymotrypsin activity
and 10,000-fold greater than the level of trypsin. In conclusion, carboxypeptidase A and B are the main proteases
involved in the digestion of proteins in the larvae of A. obliqua. The natural diet showed a high bioaccessibility.
A clear tendency to express high activities of chymotrypsin and trypsin was observed by the third instar. Our
research contributes to the planning and development of novel bioaccessibility assays to understand the nutrition
processing of A. obliqua larvae under mass-rearing conditions for sterile insect technique.
Key words: carboxypeptidases, serine proteases, digestion, midgut pH, mass-rearing diet"