Pathway improvement for ethanol production by thermophilic bacteria involving pyruvate-ferredoxin oxidoreductase and related enzymes: library development and reintroduction into C. thermocellum

• Grant number: 21/10434-4
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: September 01, 2021
• End date: February 28, 2026
• Field of knowledge: Engineering - Chemical Engineering
• Principal Investigator: Daniel Groban Olson
• Grantee: Daniela Prates Chiarelli
• Host Institution: Centro de Biologia Molecular e Engenharia Genética (CBMEG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 18/25682-0 - Advanced second generation biofuels laboratory, AP.BIOEN.SPEC
• Associated scholarship(s): 22/03642-2 - Expression and characterization of glycolytic enzymes from thermophilic bacteria in Clostridium thermocellum, BE.EP.DD

Abstract

Formation of an Advanced Second Generation (A2G) Biofuels lab based at the University of Campinas is proposed. The mission of the A2G lab is to develop and enable deployment of disruptive 2G technology for sustainable production of bioethanol from sugar cane and energy cane at much lower cost than today's technology. The central focus of the A2G lab is a new paradigm for 2G biofuel production, involving a) one-step consolidated bioprocessing (CBP) of cellulosic biomass without added enzymes using engineered thermophilic bacteria in lieu of added fungal cellulase and yeast; and b) milling during fermentation (cotreatment) in lieu of thermochemical pretreatment. This paradigm is supported by recent research results, including: demonstration that C. thermocellum, a thermophilic, anaerobic bacterium, is decisively more effective at biomass deconstruction than commercial fungal cellulase under a broad range of conditions; demonstration that cotreatment allows C. thermocellum cultures to achieve nearly complete solubilization of the carbohydrate present in several 2G feedstocks; technoeconomic analysis indicating that an advanced scenario featuring CBP with cotreatment, C-CBP, has an 8-fold shorter payback period compared to a current technology base case featuring thermochemical pretreatment and added fungal cellulase. Advancement of C-CBP will be pursued in the context of two focus areas, one addressing Microbial Cellulose Utilization and one addressing Biotechnology. A Sustainability focus area is also included addressing technoeconomic analysis, land management and greenhouse gas emissions, and social aspects. Our efforts in the sustainability domain will consider the impact and costs of bioenergy deployment with intent to achieve beneficial environmental and social outcomes. The A2G lab is to be directed by Professor Lee Lynd of Dartmouth College, and supported by a leadership team consisting of a to-be-named assistant director based at UNICAMP, and focus area leaders Evert Holwerda (Microbial Cellulose Utilization), Dan Olson (Biotechnology), and Eleanor Campbell (Sustainability). Microbial Cellulose Utilization work will be allied with the Faculty of Chemical Engineering (FEQ). Biotechnology work will be allied with the Center for Molecular Biology and Genetic Engineering (CBMEG). Sustainability work will be allied with the Faculty of Agricultural Engineering (FEAGRI). Research personnel will be cosupervised by a member of the leadership team or an international affiliated scholar along with a Brazilian affiliated scholar. A committee with significant industrial representation will advise the A2G lab. Communication modalities to ensure smooth operation and integration are anticipated. Anticipated outcomes resulting from establishment of the A2G lab as proposed herein include: UNICAMP and FAPESP becoming full partners in a multi-institutional, bi-hemispheric research and development effort aimed at a potentially transformative 2G processing paradigm; prominent research in microbial biotechnology, metabolic engineering, and microbial cellulose utilization based at CBMEG and FEQ, substantially strengthening capability in these areas both within UNICAMP and Brazil at large; initiation of promising new research directions in the sustainability domain, complementing existing strength at UNICAMP and in Brazil and laying a foundation for future initiatives; a substantial network of new international research collaborations at both individual and institutional levels. (AU)