title: Engineering transaldolase in Pichia stipitis to improve bioethanol production.
abstract: In our effort to improve the efficiency and yield of xylose-to-ethanol bioconversion in Pichia stipitis, the transaldolase (TAL) in the pentose phosphate pathway was identified as a rate-limiting enzyme for improvement. A mutant containing the Q263R change was first obtained by directed evolution with 5-fold increase of activity, which was then incorporated into P. stipitesvia the pYDS vector to produce a genetically stable strain for fermentation on xylose. In comparison with the parental strain, TAL-Q263R(+) increases ethanol prodcution by 36% and 100% as measured by volumetric production rate and specific production rate, respectively. Thus improving the transaldolase activity in P. stipitis can significantly increase the rate and yield of xylose conversion to ethanol.
authors.affiliation: Genomics Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: Shan-He
authors.initials: SH
authors.lastname: Chen
authors.forename: Der-Ren
authors.initials: DR
authors.lastname: Hwang
authors.forename: Gan-Hong
authors.initials: GH
authors.lastname: Chen
authors.forename: Ning-Shian
authors.initials: NS
authors.lastname: Hsu
authors.forename: Ying-Ta
authors.initials: YT
authors.lastname: Wu
authors.forename: Tsung-Lin
authors.initials: TL
authors.lastname: Li
authors.forename: Chi-Huey
authors.initials: CH
authors.lastname: Wong
mesh_terms: D000431:Ethanol / Q000737:chemistry / Q000378:metabolism*; D008968:Molecular Conformation; D010843:Pichia / Q000201:enzymology* / Q000378:metabolism; D015202:Protein Engineering; D014153:Transaldolase / Q000235:genetics / Q000378:metabolism*; D014994:Xylose / Q000737:chemistry / Q000378:metabolism
chemical_list: D000431:Ethanol; D014994:Xylose; D014153:Transaldolase