n-Butanol is an attractive alternative biofuel to ethanol because it can be blended with gasoline, has a higher energy content than ethanol and is also compatible with existing supply infrastructure. The current obstacle however is getting enough n-butanol, since its accumulation in native and engineered producers is highly toxic. In the journal article Functional Genomic Study of Exogenous n-Butanol Stress in Escherichia coli (E. coli), the researchers were focused on E. coli, an engineered host, and its stress responses to n-butanol. Functional genomics were used to investigate and characterize the physiological responses of E. coli when exposed to n-butanol with the hope of understanding the basis for its toxicity. Results indicate stress responses that include perturbation of respiratory functions, oxidative stress, heat shock and cell envelope stress, and stressed on metabolite transport and biosynthesis. Mutant strains of E. coli with known mutations were used to elucidate key genes in the n-butanol stress response. Genes that alleviate oxidative stress, protein misfolding and other growth defects were identified and will be targeted in the future for new studies. If the modification of these genes truly possess the defense E. coli needs to combat n-butanol exposure it will be a huge breakthrough in the biofuels world.
Investigating the E. coli stress response to n-Butanol