Cellulose-Degrading Enzymes In Termites

"Termites Could Eat into Oil's Bottom Line"
September 20 , 2006 -- By Bill Baum, Renewable Energy Access

Scientists in San Diego are using termites to advance the development of cellulosic ethanol.

In order to make the economic production of cellulosic ethanol viable and cost-effective, the discovery of new enzymes must be found in order to convert agricultural biomass to clean burning fuel. Surprisingly, one rich source of these enzymes has been found in the digestive tracts of termites.

These household pests can convert 95% of what they consume into energy within 24 hours. However, it's not the termites themselves that are doing this remarkable transformation, rather the bacteria and protozoa that inhabit their digestive tracts. These microbes naturally generate a broad range of enzymes that convert the cellulosic materials into fermentable sugars.

In the past, the U.S. has focused primarily on the production of biofuels by relying on the conversion of cornstarch into fuel ethanol. However, there has been a recent dialogue regarding the amount of corn that can be used without creating imbalances with other major industries or impacting food supplies. Additionally, it is estimated that in 2006, the U.S. will only produce between 5 billion and 15 billion gallons of ethanol from corn, which will represent less than 10% of total transportation fuels at that time.

To meet this demand for ethanol, sources other than those also serving as a food supply are needed to produce alternative fuel. The most underutilized energy asset on the planet is cellulosic biomass; cellulose-containing natural waste products are widely abundant and can be sustainably produced.

Still, the technology that works for starch isn't viable for the creation of biomass-based ethanol. Biomass has been a challenge to convert to ethanol with scientists using harsh acids and high temperatures to try to hydrolyze the cellulose molecules.

In order to solve this conversion problem, Diversa Corp., a biotech company based in San Diego, examined how biomass is converted into energy in the natural environment. They found the answer in the digestive tracts of the common termite.

During experiments, scientists dissected hundreds and thousands of individual termite intestines. Using proprietary DNA extraction and cloning technologies, they were able to isolate the cellulose-degrading enzymes. By reenacting this natural process, the company created a "cocktail" of high-performance enzymes for industrial ethanol production enablers. Although still in the early stages of this work, the initial results are promising.

The call to action to pursue a renewable energy source becomes more crucial every day. Cellulosic ethanol has enormous potential for fueling our future. Who would have guessed that the pest eating away at your floorboards may hold the key to solving our nation's gas crisis?