In California, Lawrence Livermore National Laboratory (LLNL) scientists and collaborators at the Joint BioEnergy Institute have identified a molecular mechanism in bacteria that can be manipulated to promote tolerance to imidazolium ionic liquid (IIL) solvents, and therefore overcome a key gap in biofuel and biochemical production processes. The research appears in the Journal of Bacteriology.
The team used four bacillus strains that were isolated from compost (and a mutant E. coli bacterium) and found that two of the strains and the E. coli mutant can withstand high levels of two widely used ILLs.
The normal, unmodified riboswitch interacts with guanidine and undergoes a conformational change, causing the pump to switch on and make the bacterial cells resistant to ILLs.
The results could help identify genetic engineering strategies that improve conversion of cellulosic sugars into biofuels and biochemicals in processes where a low concentration of ionic liquids surpass bacterial tolerance.