British and American scientists are unlocking the destructive powers of a wood-eating marine pest to produce cheap liquid biofuels.Helen Long has more.
EDITORS PLEASE NOTE: MUST COURTESY STILL IMAGES, LAURA MICHIE, UNIVERSITY OF PORTSMOUTH, AND ALEX BALL, NATURAL HISTORY MUSEUM They are the termites of the sea. Feeding exclusively on a diet of wood, the destructive appetite of these tiny marine pests has made gribbles the scourge of seafarers the world over. But the gribble's reputation is about to be redeemed. British and American scientists say the pier-munching isopod could be the holy grail for the next generation of liquid biofuels. Using advanced biochemical analysis and X-ray imaging techniques, the researchers have unlocked the secrets of the gribble's tough digestive system. They've mapped the structure and function of a key enzyme used to digest wood. The extremely robust and highly acidic enzyme, called a cullulase, is able to convert cellulose, an organic compound that is used to produce paper, into sugar. Here at the University of York in northern England, Professor Simon McQueen-Mason explains how the process works. (SOUNDBITE) (English) Professor Simon McQueen-Mason, York University: "Cellulases specifically chop off simple sugars from the long polymers that make up the cellulose which makes up a lot of the woody material here. So effectively they can convert part of the wood into simple sugars, though in this case the gribble takes up for its own nutrition. But in our case we are very interested in how we can convert things like wood into sugars that we can use to make biofuels." Creating liquid fuel from waste materials such as straw and wood involves breaking down the sugary carbohydrates that make up the bulk of woody biomass into simple sugars. These are then fermented to produce liquid biofuels. Until now the process has been too difficult and expensive to use on an industrial scale. But scientists have mapped the gribble enzyme's genetic blueprint and transferred it to an industrial microbe that can produce it in large quantities. (SOUNDBITE) (English) Professor Simon McQueen-Mason, York University: "We've taken the enzyme from the gribble and we've then put it into a form where we can transfer that into an industrial fungal strain that produces enzymes for things like laundry detergents. We then persuade that fungus to produce very large quantities of exact copies of the copies that the gribble produces." McQueen-Mason and his colleagues say the process will dramatically cut the costs of turning wood-based waste into biofuels. The gribble's unique enzyme is so resilient that it's able to operate in tough chemical environments, including sea water, eliminating the need for using expensive fresh water in processing. From being the bain of sailors this wood-louse of the sea could one day help power ships across the oceans.