Strain construction method for improving filamentous fungus cellulase yield and degradation capacity of lignocellulose and application of strain construction method

• Main Authors: CHAOGUANG TIAN, BANG WANG, PENGLI CAI, JINGXIAO JI, YONGSHENG JIANG, WEI YOU, YANHE MA, WENLIANG SUN, GUOLI MA, LI WAN, LIANGCAI LIN
• Format: Patent
• Language: Chinese; English
• Published: 08.06.2016
• Subjects: BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS THEREOF; CULTURE MEDIA; ENZYMOLOGY; FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIREDCHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERSFROM A RACEMIC MIXTURE; METALLURGY; MICROBIOLOGY; MICROORGANISMS OR ENZYMES; MUTATION OR GENETIC ENGINEERING; PROCESSES USING MICROORGANISMS; PROPAGATING, PRESERVING OR MAINTAINING MICROORGANISMS; SPIRITS; VINEGAR; WINE

The invention discloses a genetically engineered bacterium for high yield of cellulase and for improvement of degradation capacity of lignocellulose as well as application of the genetically engineered bacterium. A series of multi-gene mutant strains, namely delta 3 beta G delta cdt2 delta ncu05853, delta 2 beta G delta cdt2 delta ncu05853, delta 3 beta G delta cdt2 delta ncu05853 delta cre1 and delta 2 beta G delta cdt2 delta ncu05853 delta cre1, are obtained by discovering the functions of a cello-oligosaccharide transport protein like protein CLP1 (NCU05853) and by further knocking out clp1 and three beta-glucosidase genes NCU00130, NCU04952 and NCU08755, two cello-oligosaccharide transport protein genes NCU00801 (cdt-1) and NCU08114 (cdt-2) and one carbon-decomposed metabolite repressor protein CRE-1 (NCU08807) in a combined mode; and the combined mutant strain can improve the yield of cellulase and the degradation capacity of lignocellulose when cellobiose or lignocellulose serves as a substrate. The inv