Bioreactor with integrated mass-spectroscopy

• Subject Area: Process Engineering, Technical Chemistry ; Microbiology, Virology and Immunology
• Term: Funded in 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 445484440

The group of Prof. Largus (Lars) Angenent is conducting research in the field of Environmental Biotechnology at the Centre for Applied Geosciences (ZAG) at the University of Tübingen. His group will move in the beginning of 2020, together with 13 other environmental research disciplines, into the Geo- und Umweltforschungszentrum, which is a new building on the university’s campus. Angenent focuses on three core topics that have the common goal of recovering carbon from industrial gases and from organic wastewater into microbially generated fuels or other valuable chemicals (e.g., medium-chain carboxylic acids). This includes the topics of syngas fermentation, power-to-x, and chain elongation. The use of bioreactors is essential for this research. So far, the group has specifically designed and adapted these bioreactors to the respective project requirements. However, a unique design is not necessary for systems biology research with genetically modified pure cultures (e.g., Clostridium ljungdahlii, Methanothermobacter thermautotrophicus) and isotopically labelled C-containing gases. Here it is necessary to, for example, validate in-silico generated molecular biological genome-scale metabolic models (GEM) by standardized cultivation experiments to evaluate and adapt the metabolic model. In addition, genetically modified strain will be tested to answer specific research questions about the metabolic pathways. In this way, microbial metabolic processes in the fermentation of C-containing gases can be elucidated and their efficiency maximized for future biotechnological applications. Essential for the systems biology research is the use of fully automatic flow meters, which allow the supply and removal of substrate (C-containing gas) as well as the substrate turnover to be kept constant (steady-state). To evaluate the performance of the bioreactors, it is necessary to create a complete carbon balance of the incoming and outgoing C-components. A coupling of the bioreactor to a gas analysis device, which analyzes and quantifies the incoming C-gas substrate, the outgoing residual gas as well as microbial reaction products (e.g., CH4) at extremely high temporal resolution, is indispensable for this. Here, a bioreactor system with control unit and four bioreactor vessels is requested. This system allows the operation of up to four independently controllable bioreactor vessels. In addition, a gas mass spectrometer is included, which quantitatively identifies the incoming and outgoing gas phase of the respective bioreactors as well as the corresponding microbial reaction products. The advantage of a gas mass spectrometer compared to alternative measuring methods (GC-MS, infrared or gas meter) is the fast and precise measurement of organic and inorganic gas components without costly instrument conversions.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Bioreaktor mit integrierter Massenspektrometrie
• Instrumentation Group: 3520 Bakterien-Zuchtgeräte, Fermenter
• Applicant Institution: Eberhard Karls Universität Tübingen
• Leader: Professor Largus Angenent, Ph.D.