Can contribute the endosymbiont hosted in the digestive gland of Pomacea canaliculata to the dietary protein digestion?

SOPHIA MELANIE ESCOBAR CORREAS; MARTÍN SERGIO GODOY; ISRAEL A VEGA; FEDERICO A. DELLAGNOLA; JORGE HURST; MARTÍN S. GODOY; ALFREDO CASTRO VAZQUEZ; ISRAEL A. VEGA

Tucumán

Congreso; Tercer Reunión Conjunta de Sociedades de Biología; 2015

Sociedades de Biología

The digestive gland of Pomacea canaliculata is the organ most voluminous of this snail and it lodges an intracellular endosymbiont with two morphotypes identified as C and K. Enzymes and endosymbionts are secreted into digestive ducts and then travel to the stomach. Previously, we found protease activity along the digestive tract of the animal (crop, style sac and coiled intestine contents) represented by serine-protease of 30, 125, 145 and 198 kDa. Here, we studied if the endosymbiont contributes to the dietary protein digestion of this snail. In situ zymography showed that the glandular protease activity was placed on the endosymbiont and it was inhibited by aprotinin (serine-protease inhibitor). When the endosymbionts were maintained in BG11 culture medium (adjust to ~145 mOsm) for two hours, a protease of 30 kDa was found in the medium. The protease activity (fluorometric essay using DQ-gelatin as substrate and gel zymography) in the culture medium decreased when the endosymbiont were isolated from the digestive gland in presence of the streptomycin. We conclude that the endosymbiont has a serine protease of 30 kDa and its synthesis can be inhibited by streptomycin.