title: Lactobacillus buchneri strain NRRL B-30929 converts a concentrated mixture of xylose and glucose into ethanol and other products.
abstract: Lactobacillus buchneri strain NRRL B-30929 was isolated from a fuel ethanol production facility. This heterofermentative, facultative anaerobe can utilize xylose as a sole carbon source and tolerates up to 12% ethanol. Carbohydrate utilization (API, Biomerieux) and Phenotype Microarrays (PM, Biolog) analyses indicated that the strain is able to metabolize a broad spectrum of carbon sources including various monosaccharides (C5 and C6), disaccharides and oligosaccharides, with better rates under anaerobic conditions. In pH-controlled bioreactors, the bacterium consumed xylose and glucose simultaneously at high concentrations (125 g L(-1), pH 6.0). The major fermentation products were lactate (52 g L(-1)), acetate (26 g L(-1)) and ethanol (12 g L(-1)). The strain ferments glucose alone (pH 4.0) into lactate and ethanol with a molar ratio of 1.03:1. This strain will be further explored via genetic engineering for potential applications in biomass conversion.
authors.affiliation: Bioproducts and Biocatalysis Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, 1815 N. University St, Peoria, IL 61604, USA. siqing.liu@ars.usda.gov
authors.forename: Siqing
authors.initials: S
authors.lastname: Liu
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Skinner-Nemec
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Leathers
mesh_terms: D000085:Acetates / Q000378:metabolism; D000332:Aerobiosis; D000693:Anaerobiosis; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004783:Environmental Microbiology; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D007773:Lactates / Q000378:metabolism; D007778:Lactobacillus / Q000145:classification / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014994:Xylose / Q000378:metabolism*
chemical_list: D000085:Acetates; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D007773:Lactates; D012336:RNA, Ribosomal, 16S; D000431:Ethanol; D014994:Xylose; D005947:Glucose