Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 21, 2008
Publication Date: November 21, 2008
Citation: Liu, S., Bischoff, K.M., Leathers, T.D., Hughes, S.R., Rich, J.O. 2008. Make use of lactic acid bacteria in biomass to biofuel [abstract]. International Symposium on Biocatalysis and Biotechnology. Post No. M-2. p. 60. Technical Abstract: Lactic acid bacteria (LAB) have been widely used in dairy fermentations, nutraceuticals, and probiotic/prebiotic applications. Selected strains from the LAB could potentially be used as microbial catalysts for production of fuels and chemicals from lignocellulosic biomass. The unique traits of lactic acid bacteria for ethanol production include their capacity of utilizing a range of mixed substrates, their high tolerance to environmental ethanol concentrations. We have used genetic engineering approaches to modify various strains of lactic acid bacteria to improve ethanol production. Recently, we studied specific proteins expressed by Lactobacillus buchneri NRRL B-30929 at increased ethanol contents using 2D-gel electrophoresis. Comparisons of total cellular protein extracts from 0%, 6%, and 10% ethanol indicated differences in protein profiles in both 6% and 10% ethanol treated cells vs. control cells. The changes of protein levels (P<-0.05) including increases and decreases in density of each spot were analyzed. More evident changes were observed in cells exposed to 10% ethanol. The identification of ethanol stress related proteins/genes will help us to understand the molecular mechanisms governing tolerance to high ethanol concentrations. Combined with genomic analyses, the proteomic data will lead to cloning specific ethanol tolerance related genes which will be used for improving biocatalysts for increased tolerance to ethanol and other solvents.