Protein level responses of Reticulitermes flavipes gut fed on corn stover and soybean residue

Through preceding work we studied the metatranscriptomic profiles of Reticulitermes flavipes fed on the second generation feedstocks, corn stover (CS) and soybean residue (SR). To further evaluate molecular responses at the protein level, in the current study we aimed for dissecting protein profiles of R. flavipes fed on the same diets (CS and SR). Our objective was to identify novel proteins in the termite gut responding to CS and SR; and also to evaluate the activities of putative lignocellulases of R. flavipes in response to CS and SR relative to cellulose paper (control). Results from the current study corroborate with our earlier metatranscriptomic findings. There were very few differences in the protein profiles of CS and SR fed guts relative to paper. Myosin was the only protein that was significantly upregulated in SR fed guts relative to paper and CS. Activity assays of potential lignocellulases were generally similar between CS and SR fed guts. However, cellobiohydrolase activity was higher in CS-fed guts relative to paper and SR fed guts; whereas glutathione peroxidase had higher activity in SR-fed guts relative to paper and CS fed guts. With these results along with the earlier metatranscriptomic findings we hypothesize that constitutively expressed lignocellulases, along with cellobiohydrolases and glutathione peroxidases, may be important in degrading CS and SR respectively.