Symbiotic Fungus and Enzymatic Digestion in the Gut of the Termite, Macrotermes barneyi (Light) (Isoptera: Termitidae)

Abstract

Gut polysaccharidase activity was examined in the fungus-growing termite, Macrotermes barneyi (Light). Rates of enzymatic digestion of 7 polysaccharides and 5 synthetic heterosides were compared among major and minor worker midguts and hindguts and mycotêtes of the Termitomyces fungus. Major workers showed substantially more hindgut polysaccharidase activity than minor workers, though for both worker types midgut activity was substantially higher than in the hindgut. For 10 out of the 12 enzymes tested (including cellulases), activities were significantly higher in the midguts of major workers than in the fungus mycotêtes. Acquired polysaccharidases from the mycotêtes have been suggested to play a role in digestion in the termite midgut in some other Macrotermes species. However, in M. barneyi, our results indicate that for 11 of the 12 enzymes we tested acquired fungal polysaccharidases are probably of relatively little importance.