Transcriptomic and Proteomic Analyses of the Co-Culture of Clostridium saccharoperbutylacetonicum and Saccharomyces cerevisiae during Fermentation of Energy Cane to Butanol

• Grant number: 25/04192-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: October 01, 2025
• End date: September 30, 2026
• Field of knowledge: Engineering - Chemical Engineering
• Principal Investigator: Adriano Pinto Mariano
• Grantee: Bruno Xavier Ferreira
• Supervisor: Thaddeus Chukwuemeka Ezeji
• Host Institution: Faculdade de Engenharia Química (FEQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Ohio State University, Wooster, United States
• Associated to the scholarship: 23/01219-8 - Development of fermentation strategies to enable the production of butanol from energy-cane products, BP.DR

Abstract

Butanol is a compound utilized across various industries, serving both as a precursor for numerous materials and as a direct fuel source. Its production can be achieved through the Acetone-Butanol-Ethanol (ABE) fermentation process using solventogenic Clostridia, which can metabolize several carbohydrates, including glucose, arabinose, and xylose. This ability is particularly beneficial for targeting second-generation biofuels, as these sugars are primarily released during the hydrolysis of cellulose and hemicellulose structures. However, this fermentation pathway encounters challenges that render it economically unfeasible, with low titer levels in the final broth being a major concern. This low titer is largely attributed to the toxicity of butanol towards bacterial cells. To enhance butanol production, one viable strategy involves the co-cultivation of Clostridium species with other microorganisms. Literature has demonstrated that co-culturing different Clostridium species with Saccharomyces cerevisiae can yield increases in butanol production ranging from 2 % to 150 %. While this enhancement is often linked to the release of specific amino acids by the yeast during fermentation, earlier studies indicate that additional factors may also contribute to this improvement. This project aims to investigate the co-cultivation of Clostridium saccharoperbutylacetonicum with Saccharomyces cerevisiae in ABE fermentation using synthetic media and energy-cane hemicellulose hydrolysate. The objective is to explore the potential gains in butanol production from this microbial combination. To achieve this, transcriptomic and proteomic analyses will be conducted to identify the upregulated and downregulated genes, as well as the proteins expressed under varying fermentation conditions. The resulting data will be assessed using traditional statistical methods and machine learning techniques, such as Principal Component Analysis (PCA), to pinpoint the most promising genetic and/or proteomic traits to improve the efficiency of biomass conversion to butanol. Additionally, the study will test the hypothesis that the observed synergistic effects stem from a combination of amino acids and glycerol released by the yeast. This research will strengthen the collaboration with Prof. Ezeji's research group, whose expertise in Clostridium metabolism is expected to provide valuable insights into the results and advance our understanding of lignocellulosic biomass fermentation process. (AU)