1
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Tang R, Yuan X, Yang J. Problems and corresponding strategies for converting CO 2 into value-added products in Cupriavidus necator H16 cell factories. Biotechnol Adv 2023; 67:108183. [PMID: 37286176 DOI: 10.1016/j.biotechadv.2023.108183] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/17/2023] [Accepted: 05/31/2023] [Indexed: 06/09/2023]
Abstract
Elevated CO2 emissions have substantially altered the worldwide climate, while the excessive reliance on fossil fuels has exacerbated the energy crisis. Therefore, the conversion of CO2 into fuel, petroleum-based derivatives, drug precursors, and other value-added products is expected. Cupriavidus necator H16 is the model organism of the "Knallgas" bacterium and is considered to be a microbial cell factory as it can convert CO2 into various value-added products. However, the development and application of C. necator H16 cell factories has several limitations, including low efficiency, high cost, and safety concerns arising from the autotrophic metabolic characteristics of the strains. In this review, we first considered the autotrophic metabolic characteristics of C. necator H16, and then categorized and summarized the resulting problems. We also provided a detailed discussion of some corresponding strategies concerning metabolic engineering, trophic models, and cultivation mode. Finally, we provided several suggestions for improving and combining them. This review might help in the research and application of the conversion of CO2 into value-added products in C. necator H16 cell factories.
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Affiliation(s)
- Ruohao Tang
- Energy-rich Compounds Production by Photosynthetic Carbon Fixation Research Center, Shandong Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, Shandong Province, People's Republic of China; Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, Shandong Province, People's Republic of China
| | - Xianzheng Yuan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, Shandong Province, People's Republic of China
| | - Jianming Yang
- Energy-rich Compounds Production by Photosynthetic Carbon Fixation Research Center, Shandong Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, Shandong Province, People's Republic of China.
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2
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Al-Shameri A, Siebert DL, Sutiono S, Lauterbach L, Sieber V. Hydrogenase-based oxidative biocatalysis without oxygen. Nat Commun 2023; 14:2693. [PMID: 37258512 DOI: 10.1038/s41467-023-38227-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 04/21/2023] [Indexed: 06/02/2023] Open
Abstract
Biocatalysis-based synthesis can provide a sustainable and clean platform for producing chemicals. Many oxidative biocatalytic routes require the cofactor NAD+ as an electron acceptor. To date, NADH oxidase (NOX) remains the most widely applied system for NAD+ regeneration. However, its dependence on O2 implies various technical challenges in terms of O2 supply, solubility, and mass transfer. Here, we present the suitability of a NAD+ regeneration system in vitro based on H2 evolution. The efficiency of the hydrogenase-based system is demonstrated by integrating it into a multi-enzymatic cascade to produce ketoacids from sugars. The total NAD+ recycled using the hydrogenase system outperforms NOX in all different setups reaching up to 44,000 mol per mol enzyme. This system proves to be scalable and superior to NOX in terms of technical simplicity, flexibility, and total output. Furthermore, the system produces only green H2 as a by-product even in the presence of O2.
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Affiliation(s)
- Ammar Al-Shameri
- Chair of Chemistry of Biogenic Resources, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany
| | - Dominik L Siebert
- Chair of Chemistry of Biogenic Resources, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany
| | - Samuel Sutiono
- Chair of Chemistry of Biogenic Resources, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany
| | - Lars Lauterbach
- RWTH Universität Aachen, Institute of Applied Microbiology, Worringerweg 1, 52074, Aachen, Germany
| | - Volker Sieber
- Chair of Chemistry of Biogenic Resources, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany.
- Catalytic Research Center, Technical University of Munich, Ernst-Otto-Fischer-Straße 1, 85748, Garching, Germany.
- SynBiofoundry@TUM, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany.
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, 4072, Australia.
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3
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Fan Q, Waldburger S, Neubauer P, Riedel SL, Gimpel M. Implementation of a high cell density fed-batch for heterologous production of active [NiFe]-hydrogenase in Escherichia coli bioreactor cultivations. Microb Cell Fact 2022; 21:193. [PMID: 36123684 PMCID: PMC9484157 DOI: 10.1186/s12934-022-01919-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/07/2022] [Indexed: 11/13/2022] Open
Abstract
Background O2-tolerant [NiFe]-hydrogenases offer tremendous potential for applications in H2-based technology. As these metalloenzymes undergo a complicated maturation process that requires a dedicated set of multiple accessory proteins, their heterologous production is challenging, thus hindering their fundamental understanding and the development of related applications. Taking these challenges into account, we selected the comparably simple regulatory [NiFe]-hydrogenase (RH) from Cupriavidus necator as a model for the development of bioprocesses for heterologous [NiFe]-hydrogenase production. We already reported recently on the high-yield production of catalytically active RH in Escherichia coli by optimizing the culture conditions in shake flasks. Results In this study, we further increase the RH yield and ensure consistent product quality by a rationally designed high cell density fed-batch cultivation process. Overall, the bioreactor cultivations resulted in ˃130 mg L−1 of catalytically active RH which is a more than 100-fold increase compared to other RH laboratory bioreactor scale processes with C. necator. Furthermore, the process shows high reproducibility of the previously selected optimized conditions and high productivity. Conclusions This work provides a good opportunity to readily supply such difficult-to-express complex metalloproteins economically and at high concentrations to meet the demand in basic and applied studies. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01919-w.
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Affiliation(s)
- Qin Fan
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Saskia Waldburger
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Peter Neubauer
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Sebastian L Riedel
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Matthias Gimpel
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany.
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Lupacchini S, Appel J, Stauder R, Bolay P, Klähn S, Lettau E, Adrian L, Lauterbach L, Bühler B, Schmid A, Toepel J. Rewiring cyanobacterial photosynthesis by the implementation of an oxygen-tolerant hydrogenase. Metab Eng 2021; 68:199-209. [PMID: 34673236 DOI: 10.1016/j.ymben.2021.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/11/2021] [Accepted: 10/16/2021] [Indexed: 10/20/2022]
Abstract
Molecular hydrogen (H2) is considered as an ideal energy carrier to replace fossil fuels in future. Biotechnological H2 production driven by oxygenic photosynthesis appears highly promising, as biocatalyst and H2 syntheses rely mainly on light, water, and CO2 and not on rare metals. This biological process requires coupling of the photosynthetic water oxidizing apparatus to a H2-producing hydrogenase. However, this strategy is impeded by the simultaneous release of oxygen (O2) which is a strong inhibitor of most hydrogenases. Here, we addressed this challenge, by the introduction of an O2-tolerant hydrogenase into phototrophic bacteria, namely the cyanobacterial model strain Synechocystis sp. PCC 6803. To this end, the gene cluster encoding the soluble, O2-tolerant, and NAD(H)-dependent hydrogenase from Ralstonia eutropha (ReSH) was functionally transferred to a Synechocystis strain featuring a knockout of the native O2 sensitive hydrogenase. Intriguingly, photosynthetically active cells produced the O2 tolerant ReSH, and activity was confirmed in vitro and in vivo. Further, ReSH enabled the constructed strain Syn_ReSH+ to utilize H2 as sole electron source to fix CO2. Syn_ReSH+ also was able to produce H2 under dark fermentative conditions as well as in presence of light, under conditions fostering intracellular NADH excess. These findings highlight a high level of interconnection between ReSH and cyanobacterial redox metabolism. This study lays a foundation for further engineering, e.g., of electron transfer to ReSH via NADPH or ferredoxin, to finally enable photosynthesis-driven H2 production.
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Affiliation(s)
- Sara Lupacchini
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Jens Appel
- Department of Biology, Botanical Institute, University Kiel, 24118, Kiel, Germany
| | - Ron Stauder
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Paul Bolay
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Stephan Klähn
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Elisabeth Lettau
- Institute for Chemistry, Technische Universität Berlin, 10623, Berlin, Germany
| | - Lorenz Adrian
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany; Chair of Geobiotechnology, Technische Universität Berlin, 10923, Berlin, Germany
| | - Lars Lauterbach
- Institute for Chemistry, Technische Universität Berlin, 10623, Berlin, Germany; Institute of Applied Microbiology, Rheinisch-Westfälische Technische Hochschule Aachen, 52074, Aachen, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Andreas Schmid
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Jörg Toepel
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany.
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Panich J, Fong B, Singer SW. Metabolic Engineering of Cupriavidus necator H16 for Sustainable Biofuels from CO 2. Trends Biotechnol 2021; 39:412-424. [PMID: 33518389 DOI: 10.1016/j.tibtech.2021.01.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 02/08/2023]
Abstract
Decelerating global warming is one of the predominant challenges of our time and will require conversion of CO2 to usable products and commodity chemicals. Of particular interest is the production of fuels, because the transportation sector is a major source of CO2 emissions. Here, we review recent technological advances in metabolic engineering of the hydrogen-oxidizing bacterium Cupriavidus necator H16, a chemolithotroph that naturally consumes CO2 to generate biomass. We discuss recent successes in biofuel production using this organism, and the implementation of electrolysis/artificial photosynthesis approaches that enable growth of C. necator using renewable electricity and CO2. Last, we discuss prospects of improving the nonoptimal growth of C. necator in ambient concentrations of CO2.
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Affiliation(s)
- Justin Panich
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Bonnie Fong
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Steven W Singer
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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6
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Lauterbach L, Lenz O. How to make the reducing power of H 2 available for in vivo biosyntheses and biotransformations. Curr Opin Chem Biol 2018; 49:91-96. [PMID: 30544016 DOI: 10.1016/j.cbpa.2018.11.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/15/2018] [Accepted: 11/27/2018] [Indexed: 12/22/2022]
Abstract
Solar-driven electrolysis enables sustainable production of molecular hydrogen (H2), which represents a cheap and carbon-free reductant. Knallgas bacteria like Ralstonia eutropha are able to split H2 to supply energy in form of ATP and NADH, which can be subsequently used to power reactions of interest. R. eutropha employs the Calvin-Benson-Bassham cycle for the fixation of CO2, which is considered as an abundant and non-competing raw material. In this article, we summarize state-of-the-art approaches for H2-driven biosyntheses using engineered R. eutropha. Furthermore, we describe strategies for synthetic H2-driven NADH recycling. Major challenges for technical application and future perspectives are discussed.
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Affiliation(s)
- Lars Lauterbach
- Technische Universität Berlin, Department of Chemistry, Straße des 17. Juni 135, 10623 Berlin, Germany.
| | - Oliver Lenz
- Technische Universität Berlin, Department of Chemistry, Straße des 17. Juni 135, 10623 Berlin, Germany
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7
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Current state and perspectives in hydrogen production by Escherichia coli: roles of hydrogenases in glucose or glycerol metabolism. Appl Microbiol Biotechnol 2018; 102:2041-2050. [DOI: 10.1007/s00253-018-8752-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 01/07/2023]
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8
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Wu Y, Hao Y, Wei X, Shen Q, Ding X, Wang L, Zhao H, Lu Y. Impairment of NADH dehydrogenase and regulation of anaerobic metabolism by the small RNA RyhB and NadE for improved biohydrogen production in Enterobacter aerogenes. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:248. [PMID: 29093752 PMCID: PMC5663082 DOI: 10.1186/s13068-017-0938-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 10/19/2017] [Indexed: 05/27/2023]
Abstract
BACKGROUND Enterobacter aerogenes is a facultative anaerobe and is one of the most widely studied bacterial strains because of its ability to use a variety of substrates, to produce hydrogen at a high rate, and its high growth rate during dark fermentation. However, the rate of hydrogen production has not been optimized. In this present study, three strategies to improve hydrogen production in E. aerogenes, namely the disruption of nuoCDE, overexpression of the small RNA RyhB and of NadE to regulate global anaerobic metabolism, and the redistribution of metabolic flux. The goal of this study was to clarify the effect of nuoCDE, RyhB, and NadE on hydrogen production and how the perturbation of NADH influences the yield of hydrogen gas from E. aerogenes. RESULTS NADH dehydrogenase activity was impaired by knocking out nuoCD or nuoCDE in E. aerogenes IAM1183 using the CRISPR-Cas9 system to explore the consequent effect on hydrogen production. The hydrogen yields from IAM1183-CD(∆nuoC/∆nuoD) and IAM1183-CDE (∆nuoC/∆nuoD/∆nuoE) increased, respectively, by 24.5 and 45.6% in batch culture (100 mL serum bottles). The hydrogen produced via the NADH pathway increased significantly in IAM1183-CDE, suggesting that nuoE plays an important role in regulating NADH concentration in E. aerogenes. Batch-cultivating experiments showed that by the overexpression of NadE (N), the hydrogen yields of IAM1183/N, IAM1183-CD/N, and IAM1183-CDE/N increased 1.06-, 1.35-, and 1.55-folds, respectively, compared with IAM1183. Particularly worth mentioning is that the strain IAM118-CDE/N reached 2.28 mol in H2 yield, per mole of glucose consumed. IAN1183/R, IAM1183-CD/R, and IAM1183-CDE/R showed increasing H2 yields in batch culture. Metabolic flux analysis indicated that increased expression of RyhB led to a significant shift in metabolic patterns. We further investigated IAM1183-CDE/N, which had the best hydrogen-producing traits, as a potential candidate for industry applications using a 5-L fermenter; hydrogen production reached up to 1.95 times greater than that measured for IAM1183. CONCLUSIONS Knockout of nuoCD or nuoCDE and the overexpression of nadE in E. aerogenes resulted in a redistribution of metabolic flux and improved the hydrogen yield. Overexpression of RyhB had an significant change on the hydrogen production via NADH pathway. A combination of strategies would be a novel approach for developing a more economic and efficient bioprocess for hydrogen production in E. aerogenes. Finally, the latest CRISPR-Cas9 technology was successful for editing genes in E. aerogenes to develop our engineered strain for hydrogen production.
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Affiliation(s)
- Yan Wu
- Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018 China
| | - Yaqiao Hao
- Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018 China
- College of Life Science, Shenyang Normal University, Shenyang, 110034 China
| | - Xuan Wei
- Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018 China
- College of Life Science, Shenyang Normal University, Shenyang, 110034 China
| | - Qi Shen
- Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018 China
| | - Xuanwei Ding
- Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018 China
- Key Lab of Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing, 100084 China
- Department of Chemical Engineering, Institute of Biochemical Engineering, Tsinghua University, Beijing, 100084 China
- College of Life Science, Shenyang Normal University, Shenyang, 110034 China
| | - Liyan Wang
- Department of Chemical Engineering, Institute of Biochemical Engineering, Tsinghua University, Beijing, 100084 China
| | - Hongxin Zhao
- Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018 China
| | - Yuan Lu
- Key Lab of Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing, 100084 China
- Department of Chemical Engineering, Institute of Biochemical Engineering, Tsinghua University, Beijing, 100084 China
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Lamont CM, Sargent F. Design and characterisation of synthetic operons for biohydrogen technology. Arch Microbiol 2016; 199:495-503. [PMID: 27872947 PMCID: PMC5350229 DOI: 10.1007/s00203-016-1322-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 11/09/2016] [Accepted: 11/15/2016] [Indexed: 12/31/2022]
Abstract
Biohydrogen is produced by a number of microbial systems and the commonly used host bacterium Escherichia coli naturally produces hydrogen under fermentation conditions. One approach to engineering additional hydrogen production pathways is to introduce non-native hydrogenases into E. coli. An attractive candidate is the soluble [NiFe]-hydrogenase from Ralstonia eutropha, which has been shown to link NADH/NAD+ biochemistry directly to hydrogen metabolism, an activity that E. coli does not perform. In this work, three synthetic operons were designed that code for the soluble hydrogenase and two different enzyme maturase systems. Interestingly, using this system, the recombinant soluble hydrogenase was found to be assembled by the native E. coli [NiFe]-hydrogenase assembly machinery, and, vice versa, the synthetic maturase operons were able to complement E. coli mutants defective in hydrogenase biosynthesis. The heterologously expressed soluble hydrogenase was found to be active and was shown to produce biohydrogen in vivo.
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Affiliation(s)
- Ciaran M Lamont
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, MSI/WTB/JBC/DCTIR Research Complex, Dow Street, Dundee, DD1 5EH, Scotland, UK
| | - Frank Sargent
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, MSI/WTB/JBC/DCTIR Research Complex, Dow Street, Dundee, DD1 5EH, Scotland, UK.
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10
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Kelly CL, Pinske C, Murphy BJ, Parkin A, Armstrong F, Palmer T, Sargent F. Integration of an [FeFe]-hydrogenase into the anaerobic metabolism of Escherichia coli. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2015; 8:94-104. [PMID: 26839796 PMCID: PMC4694547 DOI: 10.1016/j.btre.2015.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 10/06/2015] [Indexed: 01/19/2023]
Abstract
Biohydrogen is a potentially useful product of microbial energy metabolism. One approach to engineering biohydrogen production in bacteria is the production of non-native hydrogenase activity in a host cell, for example Escherichia coli. In some microbes, hydrogenase enzymes are linked directly to central metabolism via diaphorase enzymes that utilise NAD+/NADH cofactors. In this work, it was hypothesised that heterologous production of an NAD+/NADH-linked hydrogenase could connect hydrogen production in an E. coli host directly to its central metabolism. To test this, a synthetic operon was designed and characterised encoding an apparently NADH-dependent, hydrogen-evolving [FeFe]-hydrogenase from Caldanaerobacter subterranus. The synthetic operon was stably integrated into the E. coli chromosome and shown to produce an active hydrogenase, however no H2 production was observed. Subsequently, it was found that heterologous co-production of a pyruvate::ferredoxin oxidoreductase and ferredoxin from Thermotoga maritima was found to be essential to drive H2 production by this system. This work provides genetic evidence that the Ca.subterranus [FeFe]-hydrogenase could be operating in vivo as an electron-confurcating enzyme.
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Affiliation(s)
- Ciarán L. Kelly
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
| | - Constanze Pinske
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
| | - Bonnie J. Murphy
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford OX1 3QR, UK
| | - Alison Parkin
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
| | - Fraser Armstrong
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford OX1 3QR, UK
| | - Tracy Palmer
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
| | - Frank Sargent
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
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11
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Jo BH, Cha HJ. Activation of formate hydrogen-lyase via expression of uptake [NiFe]-hydrogenase in Escherichia coli BL21(DE3). Microb Cell Fact 2015; 14:151. [PMID: 26395073 PMCID: PMC4578252 DOI: 10.1186/s12934-015-0343-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 09/16/2015] [Indexed: 11/27/2022] Open
Abstract
Background Several recent studies have reported successful hydrogen (H2) production achieved via recombinant expression of uptake [NiFe]-hydrogenases from Hydrogenovibrio marinus, Rhodobacter sphaeroides, and Escherichia coli (hydrogenase-1) in E. coli BL21(DE3), a strain that lacks H2-evolving activity. However, there are some unclear points that do not support the conclusion that the recombinant hydrogenases are responsible for the in vivo H2 production. Results Unlike wild-type BL21(DE3), the recombinant BL21(DE3) strains possessed formate hydrogen-lyase (FHL) activities. Through experiments using fdhF (formate dehydrogenase-H) or hycE (hydrogenase-3) mutants, it was shown that H2 production was almost exclusively dependent on FHL. Upon expression of hydrogenase, extracellular formate concentration was changed even in the mutant strains lacking FHL, indicating that formate metabolism other than FHL was also affected. The two subunits of H. marinus uptake [NiFe]-hydrogenase could activate FHL independently of each other, implying the presence of more than two different mechanisms for FHL activation in BL21(DE3). It was also revealed that the signal peptide in the small subunit was essential for activation of FHL via the small subunit. Conclusions Herein, we demonstrated that the production of H2 was indeed induced via native FHL activated by the expression of recombinant hydrogenases. The recombinant strains with [NiFe]-hydrogenase appear to be unsuitable for practical in vivo H2 production due to their relatively low H2 yields and productivities. We suggest that an improved H2-producing cell factory could be designed by constructing a well characterized and overproduced synthetic H2 pathway and fully activating the native FHL in BL21(DE3).
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Affiliation(s)
- Byung Hoon Jo
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 790-784, Korea.
| | - Hyung Joon Cha
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 790-784, Korea.
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12
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Heterologous expression of proteorhodopsin enhances H2 production in Escherichia coli when endogenous Hyd-4 is overexpressed. J Biotechnol 2015; 206:52-7. [PMID: 25913175 DOI: 10.1016/j.jbiotec.2015.04.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/09/2015] [Accepted: 04/11/2015] [Indexed: 11/23/2022]
Abstract
Proteorhodopsin (PR) is a light harvesting protein widely distributed among bacterioplankton that plays an integral energetic role in a new pathway of marine light capture. The conversion of light into chemical energy in non-chlorophyll-based bacterial systems could contribute to overcoming thermodynamic and metabolic constraints in biofuels production. In an attempt to improve biohydrogen production yields, H2 evolution catalyzed by endogenous hydrogenases, Hyd-3 and/or Hyd-4, was measured when recombinant proteorhodopsin (PR) was concomitantly expressed in Escherichia coli cells. Higher amounts of H2 were obtained with recombinant cells in a light and chromophore dependent manner. This effect was only observed when HyfR, the specific transcriptional activator of the hyf operon encoding Hyd-4 was overexpressed in E. coli, suggesting that an excess of protons generated by PR activity could increase hydrogen production by Hyd-4 but not by Hyd-3. Although many of the subunits of Hyd-3 and Hyd-4 are very similar, Hyd-4 possesses three additional proton-translocating NADH-ubiquinone oxidoreductase subunits, suggesting that it is dependent upon ΔμH(+). Altogether, these results suggest that protons generated by proteorhodopsin in the periplasm can only enhance hydrogen production by hydrogenases with associated proton translocating subunits.
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Boboescu IZ, Ilie M, Gherman VD, Mirel I, Pap B, Negrea A, Kondorosi É, Bíró T, Maróti G. Revealing the factors influencing a fermentative biohydrogen production process using industrial wastewater as fermentation substrate. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:139. [PMID: 25278996 PMCID: PMC4177422 DOI: 10.1186/s13068-014-0139-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 09/05/2014] [Indexed: 06/01/2023]
Abstract
BACKGROUND Biohydrogen production through dark fermentation using organic waste as a substrate has gained increasing attention in recent years, mostly because of the economic advantages of coupling renewable, clean energy production with biological waste treatment. An ideal approach is the use of selected microbial inocula that are able to degrade complex organic substrates with simultaneous biohydrogen generation. Unfortunately, even with a specifically designed starting inoculum, there is still a number of parameters, mostly with regard to the fermentation conditions, that need to be improved in order to achieve a viable, large-scale, and technologically feasible solution. In this study, statistics-based factorial experimental design methods were applied to investigate the impact of various biological, physical, and chemical parameters, as well as the interactions between them on the biohydrogen production rates. RESULTS By developing and applying a central composite experimental design strategy, the effects of the independent variables on biohydrogen production were determined. The initial pH value was shown to have the largest effect on the biohydrogen production process. High-throughput sequencing-based metagenomic assessments of microbial communities revealed a clear shift towards a Clostridium sp.-dominated environment, as the responses of the variables investigated were maximized towards the highest H2-producing potential. Mass spectrometry analysis suggested that the microbial consortium largely followed hydrogen-generating metabolic pathways, with the simultaneous degradation of complex organic compounds, and thus also performed a biological treatment of the beer brewing industry wastewater used as a fermentation substrate. CONCLUSIONS Therefore, we have developed a complex optimization strategy for batch-mode biohydrogen production using a defined microbial consortium as the starting inoculum and beer brewery wastewater as the fermentation substrate. These results have the potential to bring us closer to an optimized, industrial-scale system which will serve the dual purpose of wastewater pre-treatment and concomitant biohydrogen production.
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Affiliation(s)
- Iulian Zoltan Boboescu
- />Polytechnic University of Timisoara, Timisoara, Romania
- />Seqomics Biotechnology Ltd, Szeged, Hungary
| | - Mariana Ilie
- />Polytechnic University of Timisoara, Timisoara, Romania
| | | | - Ion Mirel
- />Polytechnic University of Timisoara, Timisoara, Romania
| | | | - Adina Negrea
- />Polytechnic University of Timisoara, Timisoara, Romania
| | - Éva Kondorosi
- />Hungarian Academy of Sciences, Biological Research Centre, Temesvari krt. 62., Szeged, 6726 Hungary
| | - Tibor Bíró
- />Szent István University, Faculty of Economics, Agricultural and Health Studies, Szarvas, Hungary
| | - Gergely Maróti
- />Polytechnic University of Timisoara, Timisoara, Romania
- />Hungarian Academy of Sciences, Biological Research Centre, Temesvari krt. 62., Szeged, 6726 Hungary
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