Termite Guts Could Lead to Bio-fuel Production
Different enzymes found in the digestive systems of termites could overcome current obstacles associated with creating fuel from wood biomass
Purdue University researchers have discovered that enzymes found in a termite's digestive system could aid in biofuel production from woody biomass.
Mike Scharf, study leader and O. Wayne Rollins/Orkin Chair in Molecular Physiology and Urban Entomology, and a team of Purdue University researchers, have found that different enzymes found in the guts of termites could overcome current obstacles associated with creating fuel from wood biomass.
Scharf and his team decided to investigate termites since they eat wood, and the wood is obviously digested within these insects. The team measured the sugar output from enzymes that are created by the termites as well as output from symbionts, which are tiny protozoa that reside within termites that help digest wood. For a long time, scientists thought symbionts were the only ones responsible for digestion until the Purdue team further investigated enzymes created by the termite host.
Termite digestive systems were separated and tested based on sections that contained and did not contain symbionts on sawdust "to measure the sugars created." The team found the different enzymes, and worked to create synthetic versions with Chesapeake Perl, which is a company that produces proteins. The genes, which created the enzymes, were placed into a virus and given to caterpillars to eat, and increased amount of the enzymes were produced.
The researchers found that the synthetic versions were capable of releasing sugar from the biomass, and also discovered that the three synthetic enzymes work on different areas of the biomass. Two of the enzymes release two different sugars -- glucose and pentose -- while the third enzyme breaks down lignin, which is a compound that makes up plant walls and is one of the toughest barriers that prevents the access to sugars in biomass.
"For the most part, people have overlooked the host termite as a source of enzymes that could be used in the production of biofuels," said Scharf. "For a long time it was thought that the symbionts were solely responsible for digestion. Certainly the symbionts do a lot, but what we've shown is that the host produces enzymes that work in synergy with the enzymes produced by those symbionts. When you combine the functions of the host enzymes with the symbionts, it's like one plus one equals four."
Accessing the sugar from plants is vital for the production of biofuels since these sugars are fermented to make ethanol. This new enzyme cocktail will allow these sugars to be created from wood, hence represents a step closer to alternative fuel production.
The next step is to find symbiont enzymes that can be mixed with termite enzymes to produce larger amounts of sugar from wood.
This study was published in PLoS One.
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