How Termites Digest Cellulose
WouterA recent study from Japan describes a previously unknown method of digesting cellulose. This discovery has led the researchers to suggest that they may be able to produce biofuels by using a combination of host and symbiont cellulases.
The termite gut is home to a large variety of microbes that play a critical role in breaking down cellulose. These microbes are called protozoa. They are amoeba-like organisms. They break down wood cellulose into simple sugars, and they also release other acids and by-products.
As part of their symbiotic relationship with termites, protozoans produce enzymes that help break down cellulose. These enzymes are secreted by protozoans into the termite’s digestive system.
The termite’s digestive system consists of two systems for digesting cellulose. One involves the midgut, where high concentrations of cellulase attack ground-up wood. The other involves the hindgut, where cellulases are used to supply energy for symbiotic bacteria.
The midgut, rumen and hindgut of the dampwood termite are the most densely populated with microbes on earth. In addition, the researchers found that the midgut produces a complete set of digestive enzymes. These enzymes are essential for the digestion of native cellulose.
The research revealed that the amount of endo-b-1,4-glucanase activity was lower in the foregut and the salivary glands. These findings are significant because they suggest that the protozoan-bacterial community in the termite’s digestive tract is stable.
These findings also suggest that the symbiotic relationship between protozoans and termites is beneficial for both. Protozoans in the termite’s digestive tract help break down cellulose into simple sugars, while the bacteria assist with the metabolic process. This triple symbiosis is essential for the termite’s ability to digest wood.
