Disocvering Ionic Liquid Resistant Genes

: Plant biomass is a rich source of sugars that can be converted to biofuels by engineered microbes. However, because the lignocellulose in biomass is insoluble in aqueous conditions and recalcitrant to enzymatic degradation, thermochemical treatment is required to break apart the lignin and cellulose polymers before sugars can be released. The most effective chemicals for doing this are known as ionic liquids, which are salts that are molten at temperatures below 100° C. Although these solvents have many unique properties that are ideal for solubilizing lignocellulose, they have been found to inhibit the growth of bacterial strains used to produce biofuels. We therefore searched for molecular mechanisms in bacteria that enable normal growth in the presence of ionic liquids and that can be engineered into our laboratory strains. To approach this, we are screening many environmental isolates as well as complex metagenomic DNA samples for ionic liquid resistance genes. Our initial studies have resulted in several genes that hold great promise for increasing the efficiency of microbial biofuel production by constructing ionic liquid tolerant strains of E. coli