How Do Termites Digest Wood?
WouterWhen we think of termites, we picture a creature that is primitive and dependent on its gut for life. That is because wood is the only food source for termites. They have gut microbes that break down the cellulose in wood into sugars that the termites can absorb.
Several species of termites have different types of microbes in their digestive tract. The termite’s gut is filled with hundreds of different kinds of bacteria, fungi and protists. These creatures aid in the digestion of food by converting essential amino acids and other compounds for the host.
The termite’s diet also affects its gene expression. In a study, scientists found that when the termite’s diet changes, so does the expression of 500 genes. Using advanced genomics techniques, researchers determined that the genes were altered when the termite consumed wood.
Those genes changed were in genes that were involved with digestion. The termite’s ability to digest wood may be a useful trait for natural selection. However, it could also be destructive ecologically.
One way that termites break down wood is with the help of an enzyme secreted by a type of microbe called a protozoan. They are a type of amoeba that lives inside the termite’s digestive system. They produce acetic acid and other acids that help the termite break down cellulose in wood.
A research team has uncovered a new microbial tool that helps termites break down wood. They used a combination of immunohistochemistry and proteomics techniques to map out the spatial distribution of cellulases in the midgut of termites.
