Gene expression and regulation of plant-polysaccharide- degrading enzymes in Penicillium oxalicum

Abstract:

Plant biomass is the most abundant renewable bioresource on earth. Many high-value added bio-based products can be produced by biomass biorefinery which needs to use plant-polysaccharide- degrading enzymes (PPDEs), such as cellulase, xylanase and raw-starch-degrading enzymes. Filamentous fungus Penicillium oxalicum can secrete complete PPDEs with high activity, but low yields of PPDEs limit their large-scale production and application. The biosynthesis of PPDEs in P. oxalicum is strictly regulated by many regulators such as transcription factors. In this review, in the biorefinery of sugarcane bagasse and raw cassava starch as feedstocks, some aspects concerning microorganisms were introduced, including the screening and breeding of fungal strains with high production of PPDEs, identification of regulatory genes regulating the biosynthesis of PPDEs and their gene expression in P. oxalicum, and construction of the engineered P. oxalicum strains with improved PPDE production, which would provide theoretical guidance for the exploration and utilization of fungal resources.

Key words:Penicillium oxalicum;regulatory gene;cellulase;xylanase;raw-starch-degrading enzyme;genetically engineered strain