title: Construction of a recombinant Trichoderma reesei strain expressing Aspergillus aculeatus β-glucosidase 1 for efficient biomass conversion.
abstract: To develop a Trichoderma reesei strain appropriate for the saccharification of pretreated cellulosic biomass, a recombinant T. reesei strain, X3AB1, was constructed that expressed an Aspergillus aculeatus β-glucosidase 1 with high specific activity under the control of the xyn3 promoter. The culture supernatant from T. reesei X3AB1 grown on 1% Avicel as a carbon source had 63- and 25-fold higher β-glucosidase activity against cellobiose compared to that of the parent strain PC-3-7 and that of the T. reesei recombinant strain expressing an endogenous β-glucosidase I, respectively. Further, the xylanase activity was 30% lower than that of PC-3-7 due to the absence of xyn3. X3AB1 grown on 1% Avicel-0.5% xylan medium produced 2.3- and 3.3-fold more xylanase and β-xylosidase, respectively, than X3AB1 grown on 1% Avicel. The supernatant from X3AB1 grown on Avicel and xylan saccharified NaOH-pretreated rice straw efficiently at a low enzyme dose, indicating that the strain has good potential for use in cellulosic biomass conversion processes.
authors.affiliation: Department of Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka 940-2188, Japan.
authors.forename: Hikaru
authors.initials: H
authors.lastname: Nakazawa
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Kawai
authors.forename: Noriko
authors.initials: N
authors.lastname: Ida
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Shida
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Okada
authors.forename: Shuji
authors.initials: S
authors.lastname: Tani
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Sumitani
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Morikawa
authors.forename: Wataru
authors.initials: W
authors.lastname: Ogasawara
mesh_terms: D001230:Aspergillus / Q000201:enzymology* / Q000235:genetics; D018533:Biomass; D002482:Cellulose / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D015870:Gene Expression; D005818:Genetic Engineering; D060847:Metabolic Engineering; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014242:Trichoderma / Q000235:genetics / Q000378:metabolism*; D014990:Xylans / Q000378:metabolism; D014995:Xylosidases / Q000378:metabolism; D001617:beta-Glucosidase / Q000235:genetics / Q000378:metabolism*
chemical_list: D003470:Culture Media; D011994:Recombinant Proteins; D014990:Xylans; D002482:Cellulose; D014995:Xylosidases; D001617:beta-Glucosidase