Roberto Mazzoli
University of Torino, Italy
Title: Construction of recombinant cellulolytic microorganisms for cellulose consolidated bioprocessing by metabolic engineering: Achievements, hurdles and perspectives
Biography
Biography: Roberto Mazzoli
Abstract
Cellulosic biomass is the most interesting substrate for biorefinery, owing to its abundance and low cost. However, cellulose is highly recalcitrant to biodegradation. Currently available technologies for fermenting cellulose to industrially relevant compounds (e.g., fuels, plastics) consist of multiple-step processes which are not cost-competitive with traditional petrochemical refinery. Engineering recombinant microbial strains able to catalyze single-step fermentation (i.e., consolidated bioprocessing, CBP) of biomass into high-value products is a key goal so as to develop cost-competitive cellulosic biomass biorefinery. For at least 20 years, intensive research efforts have been dedicated to develop recombinant strains suitable for cellulose-CBP following either the “native cellulolytic strategy”, aimed at engineering natural cellulolytic microorganisms so as to improve their product formation features or the “recombinant cellulolytic strategy” aimed at conferring cellulolytic ability to strains which naturally produce industrially-relevant products with high efficiency. Although these researches have attained impressive results, current forefront achievements yet resemble more to proofs-of-concept than to new biotechnological deliverables ready for application in industrial fermentations. The present contribution aims at providing an overview on most significant successful examples of these strategies together with major issues which still need to be addressed and possible solutions.