title: Butanol is cytotoxic to Lactococcus lactis while ethanol and hexanol are cytostatic.
abstract: Lactic acid bacteria currently used extensively by the dairy industry have a superior tolerance towards short-chain alcohols, which makes them interesting targets for use in future bio-refineries. The mechanism underlying the alcohol tolerance of lactic acid bacteria has so far received little attention. In the present study, the physiological alcohol stress response of Lactococcus lactis subsp. cremoris MG1363 towards the primary, even-chain alcohols ethanol, butanol and hexanol, was characterized. The alcohol tolerance of L. lactis was found to be comparable to those reported for highly alcohol-resistant lactic acid bacteria. Combined results from alcohol survival rate, live/dead staining, and a novel usage of the β-galactosidase assay, revealed that while high concentrations of ethanol and hexanol were cytostatic to L. lactis, high concentrations of butanol were cytotoxic, causing irreparable damages to the cell membrane.
authors.affiliation: Metabolic Signaling and Regulation Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark.
authors.forename: Anne-Mette Meisner
authors.initials: AM
authors.lastname: Hviid
authors.affiliation: Microbial Biotechnology and Biorefining Group, National Food Institute, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Ruhdal-Jensen
authors.affiliation: Metabolic Signaling and Regulation Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark.
authors.forename: Mogens
authors.initials: M
authors.lastname: Kilstrup
mesh_terms: D056804:Biofuels / Q000382:microbiology; D000440:Butanols / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects*; D000431:Ethanol / Q000494:pharmacology*; D000441:Hexanols / Q000494:pharmacology*; D013294:Lactococcus lactis / Q000187:drug effects* / Q000235:genetics; D008826:Microbial Sensitivity Tests
chemical_list: D056804:Biofuels; D000440:Butanols; D000441:Hexanols; D000431:Ethanol