TY  - JOUR
A1  - Burger, Yvonne
A1  - Schwarz, Fabian M.
A1  - Müller, Volker
T1  - Formate-driven H₂ production by whole cells of Thermoanaerobacter kivui
T2  - Biotechnology for biofuels and bioproducts
N2  - Background: In times of global warming there is an urgent need to replace fossil fuel-based energy vectors by less carbon dioxide (CO2)-emitting alternatives. One attractive option is the use of molecular hydrogen (H2) since its combustion emits water (H2O) and not CO2. Therefore, H2 is regarded as a non-polluting fuel. The ways to produce H2 can be diverse, but steam reformation of conventional fossil fuel sources is still the main producer of H2 gas up to date. Biohydrogen production via microbes could be an alternative, environmentally friendly and renewable way of future H2 production, especially when the flexible and inexpensive C1 compound formate is used as substrate.
Results: In this study, the versatile compound formate was used as substrate to drive H2 production by whole cells of the thermophilic acetogenic bacterium Thermoanaerobacter kivui which harbors a highly active hydrogen-dependent CO2 reductase (HDCR) to oxidize formate to H2 and CO2 and vice versa. Under optimized reaction conditions, T. kivui cells demonstrated the highest H2 production rates (qH2 = 685 mmol g−1 h−1) which were so far reported in the literature for wild-type organisms. Additionally, high yields (Y(H2/formate)) of 0.86 mol mol−1 and a hydrogen evolution rate (HER) of 999 mmol L−1 h−1 were observed. Finally, stirred-tank bioreactor experiments demonstrated the upscaling feasibility of the applied whole cell system and indicated the importance of pH control for the reaction of formate-driven H2 production.
Conclusions: The thermophilic acetogenic bacterium T. kivui is an efficient biocatalyst for the oxidation of formate to H2 (and CO2). The existing genetic tool box of acetogenic bacteria bears further potential to optimize biohydrogen production in future and to contribute to a future sustainable formate/H2 bio-economy.
KW  - Biohydrogen
KW  - Dark fermentation
KW  - Acetogenic bacteria
KW  - Bioreactor
KW  - qH2
KW  - HER
KW  - Optimization
KW  - Scale-up
KW  - Hydrogen-dependent CO2 reductase (HDCR)
Y1  - 2022
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/69491
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-694915
SN  - 2731-3654
N1  - This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant agreement no. 741791).
N1  - Open Access funding enabled and organized by Projekt DEAL.
N1  - Gefördert durch den Open-Access-Publikationsfonds der Goethe-Universität
VL  - 15
IS  - art. 48
SP  - 1
EP  - 12
PB  - BioMed Central
CY  - London
ER  -