The Great Salt Lake in Utah (Courtesy of Charles Uibel, GreatSaltLakePhotos.com)
To overcome the difficulties of converting cellulosic biomass into high energy-content fuel, researchers have been seeking to improve various stages of the process. One big obstacle that stands in the way is that most enzymes are inefficient at breaking down biomass when in the presence of ionic liquids, solvents that have proven effective at treating the biomass and enhancing conversion to fermentable sugars that come from the plant.
However, researchers from the DOE JGI and Joint BioEnergy Institute (JBEI) have partnered to create a solution to this problem. Published online July 1 in the journal Green Chemistry, these scientists, including DOE JGI director Eddy Rubin, targeted halophilic (salt-tolerant) enzymes, specifically those living in the Great Salt Lake,
with the idea that if they can survive this extreme environment, they could then tolerate ionic liquids. Their experiments focused on one specific enzyme from the archaeon, Halorhabdusutahensis.
Scientists at the DOE JGI sequenced this microbe and with collaborators at JBEI managed to test the practicality of its enzymes with positive results. They showed that such salt-tolerant enzymes, particularly cellulases, offer significant advantages for industrial utility over conventional enzymes.
“This project has established a very important link between genomic science and the realization of enzymes that can handle very demanding chemical environments, such as those present in a biorefinery,” said study co-author Blake Simmons, Vice-President of the JBEI Deconstruction Division.