IMPROVING BIOCHEMICAL PROCESSES FOR THE PRODUCTION OF SUSTAINABLE FUELS AND CHEMICALS
Location: Renewable Product Technology Research Unit
Title: Adaptation of lactic acid bacteria to butanol
Submitted to: Biocatalysis and Agricultural Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 22, 2011
Publication Date: January 1, 2012
Citation: Liu, S., Bischoff, K.M., Leathers, T.D., Qureshi, N., Rich, J.O., Hughes, S.R. 2012. Adaptation of lactic acid bacteria to butanol. Biocatalysis and Agricultural Biotechnology. 1(1):57-61. DOI: http://dx.doi.org/10.1016/j.bcab.2011.08.008.
Interpretive Summary: New and improved biocatalysts are needed to convert renewable lignocellulosic biomass into biofuels and chemicals. Cost effective production and recovery of biofuel butanol relies on developing robust microbes that tolerate end-product butanol. Butanol tolerant microbes can be used as metabolic engineering hosts for butanol production. In the present study, bacteria were isolated from commercial ethanol plants and these isolates were challenged and adapted with increased butanol and ten strains were selected for high butanol tolerance. This information will be of interest to butanol producers and researchers in developing new robust strains for butanol production.
Butanol can be produced biologically through fermentation of various substrates by Gram-positive Clostridium species. However, to profitably produce butanol at industrial scales, new microbial biocatalysts with increased tolerance to butanol are needed. In this study we report the isolation and selection of microbeswith increased tolerance to butanol. Ten strains including L. mucosae strains BR0605-3, BR0605-B15, BR0713-18, BR0713-20, BR0713-30, BR0713-33, L. amylovorus strain NE-L 0206-19, Pediococcus parvulus NE-L 0206-31, Lactobacillus crispatus NE-L 0206-47, and Weissella confusa BR0216-18 were found capable of growth in 3- 4% butanol after long term adaptation. These strains can be used to study tolerance mechanisms as well as identifying specific butanol stress response genes for development of butanol tolerant microbes.