Wood digestion in lower termites: multidisciplinary approaches based on differential feeding

Termites digestive tract and hindgut especially still holds many secrets despites hundreds of years of research. The complexity of the symbiotic microbial community and the contrast of physio-chemical environments found in lower termites paunch are potentially the key point to explain the efficiency of ligno-cellulose digestion. Contribution of advancing technologies accelerates the progress of our knowledge in this field. Here, we present multiple approaches combining old and recent techniques used to highlight the effect of ligno-cellulosic compounds on termite gut and the role of populations from the symbiotic microbial community. Termites Reticulitermes flavipes (Kollar) submitted to various artificial diets showed variations in flagellates populations profile and enzymatic activities. Differential protein expression was investigated using 2D-DIGE MALDI-TOF-TOF and 2D-LC-MS/MS using high resolution orbitrap analyzer. Results from both proteomic experiments tend to support each-other and bring complementary points of view. The gel-free analysis resulted in highly contrasted identification of enzymes involved in ligno-cellulose digestion and metabolism. Finally, differential feeding experiments leaded to in vivo selection of different symbiotic communities. These communities were characterized following some metabolism assays and allowed the cultivation of diverse microbial consortia using media closely related to the respective artificial diets. This work provides relevant data on termite and associated microbial community response to alimentary diets.