title: Functional expression of Burkholderia cenocepacia xylose isomerase in yeast increases ethanol production from a glucose-xylose blend.
abstract: This study presents results regarding the successful cloning of the bacterial xylose isomerase gene (xylA) of Burkholderia cenocepacia and its functional expression in Saccharomyces cerevisiae. The recombinant yeast showed to be competent to efficiently produce ethanol from both glucose and xylose, which are the main sugars in lignocellulosic hydrolysates. The heterologous expression of the gene xylA enabled a laboratorial yeast strain to ferment xylose anaerobically, improving ethanol production from a fermentation medium containing a glucose-xylose blend similar to that found in sugar cane bagasse hydrolysates. The insertion of xylA caused a 5-fold increase in xylose consumption, and over a 1.5-fold increase in ethanol production and yield, in comparison to that showed by the WT strain, in 24h fermentations, where it was not detected accumulation of xylitol. These findings are encouraging for further studies concerning the expression of B. cenocepacia xylA in an industrial yeast strain.
authors.affiliation: Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: de Figueiredo Vilela
authors.forename: Vinicius Mattos
authors.initials: VM
authors.lastname: de Mello
authors.forename: Viviane Castelo Branco
authors.initials: VC
authors.lastname: Reis
authors.forename: Elba Pinto da Silva
authors.initials: EP
authors.lastname: Bon
authors.forename: Fernando Araripe
authors.initials: FA
authors.lastname: Gonçalves Torres
authors.forename: Bianca Cruz
authors.initials: BC
authors.lastname: Neves
authors.forename: Elis Cristina Araújo
authors.initials: EC
authors.lastname: Eleutherio
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000235:genetics / Q000378:metabolism*; D057508:Burkholderia cenocepacia / Q000502:physiology*; D000431:Ethanol / Q000302:isolation & purification / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D015202:Protein Engineering / Q000379:methods; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D014994:Xylose / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D000431:Ethanol; D014994:Xylose; D019747:Aldose-Ketose Isomerases; C023298:xylose isomerase; D005947:Glucose