Termites might be destructive pests — they cause more than $1 billion in damage every year in the US alone — but they could also hold the secret to converting plant material into renewable, sustainable fuel.
Researchers at the University of Florida (UF) have been studying how the insects digest wood via a mixture of enzymes from bacteria and other single-celled creatures that live in termites’ guts, as well as enzymes from termites themselves. After two years of dissecting and analysing gene sequences from termite guts and gut fauna, the research team has now begun to identify which of those genes encode for enzymes that could be used to improve the production of cellulosic ethanol.
Cellulosic ethanol is a fuel made from wood chips, corn stover and other inedible plant materials. According to the US Department of Energy, cellulosic ethanol could replace half of the nation’s gasoline if the production process could be made more efficient and cost effective.
“Termites are very unique creatures, and this research helps give the most complete picture of how their systems collaborate to, very efficiently, break down really tough biological compounds to release fermentable sugars,” said Mike Scharf, a UF entomologist who’s heading the research effort.
The UF team has identified nearly 200 enzymes that help break down the problematic plant compound lignocellulose. This compound is the most costly barrier to wide-scale production of cellulosic ethanol because it must be broken down by intense heat or caustic chemicals.
Termites, however, are able to almost completely break down lignocellulose through simple digestion.
“The termite gut is a complicated and exotic package of biodiversity that manages these tasks with an efficiency that you really have to admire,” said Claudia Husseneder, a specialist in the molecular biology of termites at Louisiana State University who was not associated with UF’s research. “Mike’s work is on the cutting edge of understanding this system.”
In September, Scharf and the Maryland-based firm Chesapeake-PERL Inc. received a $750,000 grant from the US Department of Energy to help develop his work into a product that can be used to help manufacture cellulosic ethanol.
Except for their genes, termites and their associated single-cell symbiotic organisms probably won’t have much to do with the processes that result from the work. The enzyme-producing genes would probably be transferred to a more controllable creature, Scharf said
Typically, this has meant using genetically modified fungi or bacteria. However, Scharf said the genes would likely be transferred into other insects, such as caterpillars, to produce the enzymes on an industrial scale.
“Insects have played an important role in how this planet functions for millions of years,” Scharf said. “They still have a lot they can teach us. There are still many ways we can learn to benefit from Earth’s six-legged inhabitants.”