Details

Autor(en) / Beteiligte

• da Silva Delabona, Priscila
• Rodrigues, Gisele Nunes
• Zubieta, Mariane Paludetti
• Ramoni, Jonas
• Codima, Carla Aloia
• Lima, Deise Juliana
• Farinas, Cristiane Sanchez
• da Cruz Pradella, José Geraldo
• Seiboth, Bernhard

Titel

The relation between xyr1 overexpression in Trichoderma harzianum and sugarcane bagasse saccharification performance

Ist Teil von

• Journal of biotechnology, 2017-03, Vol.246, p.24-32

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2017

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• •The role of xyr1 (xylanase regulator 1) in the cellulases production by Trichoderma harzianum.•Relevant improvement of genes expression encoding enzymes involved in biomass degradation by xyr1 clone overexpression.•New enzymatic complex by T. harzianuḿs xyr1 overexpression used in sugarcane bagasse saccharification. This work investigates the influence of the positive regulator XYR1 of Trichoderma harzianum on the production of cellulolytic enzymes, using sugarcane bagasse as carbon source. Constitutive expression of xyr1 was achieved under the control of the strong Trichoderma reesei pki1 promoter. Five clones with xyr1 overexpression achieved higher xyr1 expression and greater enzymatic productivity when cultivated under submerged fermentation, hence validating the genetic construction for T. harzianum. Clone 5 presented a relative expression of xyr1 26-fold higher than the parent strain and exhibited 66, 37, and 36% higher values for filter paper activity, xylanase activity, and β-glucosidase activity, respectively, during cultivation in a stirred-tank bioreactor. The overexpression of xyr1 in T. harzianum resulted in an enzymatic complex with significantly improved performance in sugarcane bagasse saccharification, with an enhancement of 25% in the first 24h. Our results also show that constitutive overexpression of xyr1 leads to the induction of several important players in biomass degradation at early (24h) and also late (48h) timepoints of inoculation. However, we also observed that the carbon catabolite repressor CRE1 was upregulated in xyr1 overexpression mutants. These findings demonstrate the feasibility of improving cellulase production by modifying regulator expression and suggest an attractive approach for increasing total cellulase productivity in T. harzianum.