Improved Saccharification of Wheat Straw for Biofuel Production Using an Engineered Secretome of Trichoderma reesei

详细信息    查看全文

• 作者：Ce虂line Ayrinhac ; Antoine Margeot ; Nicolas Lopes Ferreira ; Fadhel Ben Chaabane ; Fre虂de虂ric Monot ; Gilles Ravot ; Jean-Marie Sonet ; Laurent Fourage
• 刊名：Organic Process Research & Development
• 出版年：2011
• 出版时间：January 21, 2011
• 年：2011
• 卷：15
• 期：1
• 页码：275-278
• 全文大小：163K
• 年卷期：v.15,no.1(January 21, 2011)
• ISSN：1520-586X

文摘

For the purpose of a industrial process of cellulosic ethanol production, an efficient 尾-glucosidase was evolved by L-Shuffling starting from three parental genes (i.e., Chaetomium globosum glucosidase putative gene, Trichoderma reesei bgl1 gene, and Neurospora crassa glucosidase putative gene, named genes A, B, and C, respectively) originating from microbial biodiversity and showing 70% of identity at the amino acid level. Enzyme B (encoded by bgl1 gene) was chosen as a reference so that the backbone of the evolved enzymes would be based on this enzyme. Two rounds of L-Shuffling and colonies screening (20,000 colonies per round) on chromogenic glucose substrate were performed. Compared with native 尾-glucosidase, the most evolved enzyme has a 242-fold increased k_cat for the pNPGlc substrate. After expression of this improved 尾-glucosidase in T. reesei, a new efficient enzymatic cocktail was secreted by the strain allowing for a 4-fold decrease in cellulase loading without any loss in hydrolysis performance of degradation of a steam-exploded wheat straw compared to the untransformed parental strain.