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Santolin L, Riedel SL, Brigham CJ. Synthetic biology toolkit of Ralstonia eutropha (Cupriavidus necator). Appl Microbiol Biotechnol 2024; 108:450. [PMID: 39207499 PMCID: PMC11362209 DOI: 10.1007/s00253-024-13284-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Revised: 08/09/2024] [Accepted: 08/12/2024] [Indexed: 09/04/2024]
Abstract
Synthetic biology encompasses many kinds of ideas and techniques with the common theme of creating something novel. The industrially relevant microorganism, Ralstonia eutropha (also known as Cupriavidus necator), has long been a subject of metabolic engineering efforts to either enhance a product it naturally makes (polyhydroxyalkanoate) or produce novel bioproducts (e.g., biofuels and other small molecule compounds). Given the metabolic versatility of R. eutropha and the existence of multiple molecular genetic tools and techniques for the organism, development of a synthetic biology toolkit is underway. This toolkit will allow for novel, user-friendly design that can impart new capabilities to R. eutropha strains to be used for novel application. This article reviews the different synthetic biology techniques currently available for modifying and enhancing bioproduction in R. eutropha. KEY POINTS: • R. eutropha (C. necator) is a versatile organism that has been examined for many applications. • Synthetic biology is being used to design more powerful strains for bioproduction. • A diverse synthetic biology toolkit is being developed to enhance R. eutropha's capabilities.
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Affiliation(s)
- Lara Santolin
- Technische Universität Berlin, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
| | - Sebastian L Riedel
- Berliner Hochschule Für Technik, Department VIII - Mechanical Engineering, Event Technology and Process Engineering, Environmental and Bioprocess Engineering Laboratory, Berlin, Germany.
| | - Christopher J Brigham
- Department of Bioengineering, University of Massachusetts Dartmouth, North Dartmouth, MA, USA.
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Hiralal A, Geelhoed JS, Neukirchen S, Meysman FJR. Comparative genomic analysis of nickel homeostasis in cable bacteria. BMC Genomics 2024; 25:692. [PMID: 39009997 PMCID: PMC11247825 DOI: 10.1186/s12864-024-10594-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 07/03/2024] [Indexed: 07/17/2024] Open
Abstract
BACKGROUND Cable bacteria are filamentous members of the Desulfobulbaceae family that are capable of performing centimetre‑scale electron transport in marine and freshwater sediments. This long‑distance electron transport is mediated by a network of parallel conductive fibres embedded in the cell envelope. This fibre network efficiently transports electrical currents along the entire length of the centimetre‑long filament. Recent analyses show that these fibres consist of metalloproteins that harbour a novel nickel‑containing cofactor, which indicates that cable bacteria have evolved a unique form of biological electron transport. This nickel‑dependent conduction mechanism suggests that cable bacteria are strongly dependent on nickel as a biosynthetic resource. Here, we performed a comprehensive comparative genomic analysis of the genes linked to nickel homeostasis. We compared the genome‑encoded adaptation to nickel of cable bacteria to related members of the Desulfobulbaceae family and other members of the Desulfobulbales order. RESULTS Presently, four closed genomes are available for the monophyletic cable bacteria clade that consists of the genera Candidatus Electrothrix and Candidatus Electronema. To increase the phylogenomic coverage, we additionally generated two closed genomes of cable bacteria: Candidatus Electrothrix gigas strain HY10‑6 and Candidatus Electrothrix antwerpensis strain GW3‑4, which are the first closed genomes of their respective species. Nickel homeostasis genes were identified in a database of 38 cable bacteria genomes (including 6 closed genomes). Gene prevalence was compared to 19 genomes of related strains, residing within the Desulfobulbales order but outside of the cable bacteria clade, revealing several genome‑encoded adaptations to nickel homeostasis in cable bacteria. Phylogenetic analysis indicates that nickel importers, nickel‑binding enzymes and nickel chaperones of cable bacteria are affiliated to organisms outside the Desulfobulbaceae family, with several proteins showing affiliation to organisms outside of the Desulfobacterota phylum. Conspicuously, cable bacteria encode a unique periplasmic nickel export protein RcnA, which possesses a putative cytoplasmic histidine‑rich loop that has been largely expanded compared to RcnA homologs in other organisms. CONCLUSION Cable bacteria genomes show a clear genetic adaptation for nickel utilization when compared to closely related genera. This fully aligns with the nickel‑dependent conduction mechanism that is uniquely found in cable bacteria.
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Affiliation(s)
- Anwar Hiralal
- Geobiology Research Group, University of Antwerp, Antwerp, Belgium
| | | | - Sinje Neukirchen
- Geobiology Research Group, University of Antwerp, Antwerp, Belgium
| | - Filip J R Meysman
- Geobiology Research Group, University of Antwerp, Antwerp, Belgium.
- Department of Biotechnology, Delft University of Technology, Delft, The Netherlands.
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Chen K, Ma C, Cheng X, Wang Y, Guo K, Wu R, Zhu Z. Construction of Cupriavidus necator displayed with superoxide dismutases for enhanced growth in bioelectrochemical systems. BIORESOUR BIOPROCESS 2023; 10:36. [PMID: 38647886 PMCID: PMC10992759 DOI: 10.1186/s40643-023-00655-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/28/2023] [Indexed: 04/25/2024] Open
Abstract
It is of great significance to utilize CO2 as feedstock to synthesize biobased products, particularly single cell protein (SCP) as the alternative food and feed. Bioelectrochemical system (BES) driven by clean electric energy has been regarded as a promising way for Cupriavidus necator to produce SCP from CO2 directly. At present, the key problem of culturing C. necator in BES is that reactive oxygen species (ROS) generated in cathode chamber are harmful to bacterial growth. Therefore, it is necessary to find a solution to mitigate the negative effect of ROS. In this study, we constructed a number of C. necator strains displayed with superoxide dismutase (SOD), which allowed the decomposition of superoxide anion radical. The effects of promoters and signal peptides on the cell surface displayed SOD were analyzed. The proteins displayed on the surface were further verified by the fluorescence experiment. Finally, the growth of C. necator CMS incorporating a pBAD-SOD-E-tag-IgAβ plasmid could achieve 4.9 ± 1.0 of OD600 by 7 days, equivalent to 1.7 ± 0.3 g/L dry cell weight (DCW), and the production rate was 0.24 ± 0.04 g/L/d DCW, around 2.7-fold increase than the original C. necator CMS (1.8 ± 0.3 of OD600). This study can provide an effective and novel strategy of cultivating strains for the production of CO2-derived SCP or other chemicals in BES.
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Affiliation(s)
- Ke Chen
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, The College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xiqidao, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Chunling Ma
- Haihe Laboratory of Synthetic Biology, 21 Xishiwudao, Tianjin Airport Economic Park, Tianjin, 300308, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xiqidao, Tianjin Airport Economic Park, Tianjin, 300308, China
- School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Xiaolei Cheng
- University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing, 100049, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xiqidao, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Yuhua Wang
- University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing, 100049, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xiqidao, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Kun Guo
- School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Ranran Wu
- University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing, 100049, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xiqidao, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Zhiguang Zhu
- University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing, 100049, China.
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xiqidao, Tianjin Airport Economic Park, Tianjin, 300308, China.
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Wei H, Wang W, Chou YC, Himmel ME, Chen X, Bomble YJ, Zhang M. Prospects for engineering Ralstonia eutropha and Zymomonas mobilis for the autotrophic production of 2,3-butanediol from CO 2 and H 2. ENGINEERING MICROBIOLOGY 2023; 3:100074. [PMID: 39629244 PMCID: PMC11610990 DOI: 10.1016/j.engmic.2023.100074] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 01/02/2023] [Accepted: 01/06/2023] [Indexed: 12/07/2024]
Abstract
The decarbonization of the chemical industry and a shift toward circular economies because of high global CO2 emissions make CO2 an attractive feedstock for manufacturing chemicals. Moreover, H2 is a low-cost and carbon-free reductant because technologies such as solar-driven electrolysis and supercritical water (scH2O) gasification enable sustainable production of molecular hydrogen (H2). We review the recent advances in engineering Ralstonia eutropha, the representative species of "Knallgas" bacteria, for utilizing CO2 and H2 to autotrophically produce 2,3-butanediol (2,3-BDO). This assessment is focused on state-of-the-art approaches for splitting H2 to supply energy in the form of ATP and NADH to power cellular reactions and employing the Calvin-Benson-Bassham cycle for CO2 fixation. Major challenges and opportunities for application and future perspectives are discussed in the context of developing other promising CO2 and H2-utilizing microorganisms, exemplified by Zymomonas mobilis.
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Affiliation(s)
- Hui Wei
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Wei Wang
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Yat-Chen Chou
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Michael E. Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Xiaowen Chen
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Yannick J. Bomble
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Min Zhang
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
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Cha J, Bak H, Kwon I. Hydrogen-fueled CO 2 reduction using oxygen-tolerant oxidoreductases. Front Bioeng Biotechnol 2023; 10:1078164. [PMID: 36686231 PMCID: PMC9849572 DOI: 10.3389/fbioe.2022.1078164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/22/2022] [Indexed: 01/06/2023] Open
Abstract
Hydrogen gas obtained from cheap or sustainable sources has been investigated as an alternative to fossil fuels. By using hydrogenase (H2ase) and formate dehydrogenase (FDH), H2 and CO2 gases can be converted to formate, which can be conveniently stored and transported. However, developing an enzymatic process that converts H2 and CO2 obtained from cheap sources into formate is challenging because even a very small amount of O2 included in the cheap sources damages most H2ases and FDHs. In order to overcome this limitation, we investigated a pair of oxygen-tolerant H2ase and FDH. We achieved the cascade reaction between H2ase from Ralstonia eutropha H16 (ReSH) and FDH from Rhodobacter capsulatus (RcFDH) to convert H2 and CO2 to formate using in situ regeneration of NAD+/NADH in the presence of O2.
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Affiliation(s)
- Jaehyun Cha
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Hyeonseon Bak
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Inchan Kwon
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea,Research Center for Innovative Energy and Carbon Optimized Synthesis for Chemicals (Inn-ECOSysChem), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea,*Correspondence: Inchan Kwon,
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Wickham-Smith C, Malys N, Winzer K. Improving carbon monoxide tolerance of Cupriavidus necator H16 through adaptive laboratory evolution. Front Bioeng Biotechnol 2023; 11:1178536. [PMID: 37168609 PMCID: PMC10164946 DOI: 10.3389/fbioe.2023.1178536] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 04/06/2023] [Indexed: 05/13/2023] Open
Abstract
Background: The toxic gas carbon monoxide (CO) is abundantly present in synthesis gas (syngas) and certain industrial waste gases that can serve as feedstocks for the biological production of industrially significant chemicals and fuels. For efficient bacterial growth to occur, and to increase productivity and titres, a high resistance to the gas is required. The aerobic bacterium Cupriavidus necator H16 can grow on CO2 + H2, although it cannot utilise CO as a source of carbon and energy. This study aimed to increase its CO resistance through adaptive laboratory evolution. Results: To increase the tolerance of C. necator to CO, the organism was continually subcultured in the presence of CO both heterotrophically and autotrophically. Ten individual cultures were evolved heterotrophically with fructose in this manner and eventually displayed a clear growth advantage over the wild type strain. Next-generation sequencing revealed several mutations, including a single point mutation upstream of a cytochrome bd ubiquinol oxidase operon (cydA2B2), which was present in all evolved isolates. When a subset of these mutations was engineered into the parental H16 strain, only the cydA2B2 upstream mutation enabled faster growth in the presence of CO. Expression analysis, mutation, overexpression and complementation suggested that cydA2B2 transcription is upregulated in the evolved isolates, resulting in increased CO tolerance under heterotrophic but not autotrophic conditions. However, through subculturing on a syngas-like mixture with increasing CO concentrations, C. necator could also be evolved to tolerate high CO concentrations under autotrophic conditions. A mutation in the gene for the soluble [NiFe]-hydrogenase subunit hoxH was identified in the evolved isolates. When the resulting amino acid change was engineered into the parental strain, autotrophic CO resistance was conferred. A strain constitutively expressing cydA2B2 and the mutated hoxH gene exhibited high CO tolerance under both heterotrophic and autotrophic conditions. Conclusion: C. necator was evolved to tolerate high concentrations of CO, a phenomenon which was dependent on the terminal respiratory cytochrome bd ubiquinol oxidase when grown heterotrophically and the soluble [NiFe]-hydrogenase when grown autotrophically. A strain exhibiting high tolerance under both conditions was created and presents a promising chassis for syngas-based bioproduction processes.
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Comparative Metagenomics Highlight a Widespread Pathway Involved in Catabolism of Phosphonates in Marine and Terrestrial Serpentinizing Ecosystems. mSystems 2022; 7:e0032822. [PMID: 35913189 PMCID: PMC9426474 DOI: 10.1128/msystems.00328-22] [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] [Indexed: 11/20/2022] Open
Abstract
Serpentinizing hydrothermal systems result from water circulating into the subsurface and interacting with mantle-derived rocks notably near mid-ocean ridges or continental ophiolites. Serpentinization and associated reactions produce alkaline fluids enriched in molecular hydrogen, methane, and small organic molecules that are assumed to feed microbial inhabitants. In this study, we explored the relationships linking serpentinization to associated microbial communities by comparative metagenomics of serpentinite-hosted systems, basalt-hosted vents, and hot springs. The shallow Prony bay hydrothermal field (PBHF) microbiome appeared to be more related to those of ophiolitic sites than to the Lost City hydrothermal field (LCHF) microbiome, probably because of the meteoric origin of its fluid, like terrestrial alkaline springs. This study emphasized the ubiquitous importance of a set of genes involved in the catabolism of phosphonates and highly enriched in all serpentinizing sites compared to other ecosystems. Because most of the serpentinizing systems are depleted in inorganic phosphate, the abundance of genes involved in the carbon-phosphorus lyase pathway suggests that the phosphonates constitute a source of phosphorus in these ecosystems. Additionally, hydrocarbons such as methane, released upon phosphonate catabolism, may contribute to the overall budget of organic molecules in serpentinizing systems. IMPORTANCE This first comparative metagenomic study of serpentinite-hosted environments provides an objective framework to understand the functioning of these peculiar ecosystems. We showed a taxonomic similarity between the PBHF and other terrestrial serpentinite-hosted ecosystems. At the same time, the LCHF microbial community was closer to deep basalt-hosted hydrothermal fields than continental ophiolites, despite the influence of serpentinization. This study revealed shared functional capabilities among serpentinite-hosted ecosystems in response to environmental stress, the metabolism of abundant dihydrogen, and the metabolism of phosphorus. Our results are consistent with the generalized view of serpentinite environments but provide deeper insight into the array of factors that may control microbial activities in these ecosystems. Moreover, we show that metabolism of phosphonate is widespread among alkaline serpentinizing systems and could play a crucial role in phosphorus and methane biogeochemical cycles. This study opens a new line of investigation of the metabolism of reduced phosphorus compounds in serpentinizing environments.
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Lambauer V, Kratzer R. Lab-Scale Cultivation of Cupriavidus necator on Explosive Gas Mixtures: Carbon Dioxide Fixation into Polyhydroxybutyrate. Bioengineering (Basel) 2022; 9:204. [PMID: 35621482 PMCID: PMC9138072 DOI: 10.3390/bioengineering9050204] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/29/2022] [Accepted: 05/05/2022] [Indexed: 11/16/2022] Open
Abstract
Aerobic, hydrogen oxidizing bacteria are capable of efficient, non-phototrophic CO2 assimilation, using H2 as a reducing agent. The presence of explosive gas mixtures requires strict safety measures for bioreactor and process design. Here, we report a simplified, reproducible, and safe cultivation method to produce Cupriavidus necator H16 on a gram scale. Conditions for long-term strain maintenance and mineral media composition were optimized. Cultivations on the gaseous substrates H2, O2, and CO2 were accomplished in an explosion-proof bioreactor situated in a strong, grounded fume hood. Cells grew under O2 control and H2 and CO2 excess. The starting gas mixture was H2:CO2:O2 in a ratio of 85:10:2 (partial pressure of O2 0.02 atm). Dissolved oxygen was measured online and was kept below 1.6 mg/L by a stepwise increase of the O2 supply. Use of gas compositions within the explosion limits of oxyhydrogen facilitated production of 13.1 ± 0.4 g/L total biomass (gram cell dry mass) with a content of 79 ± 2% poly-(R)-3-hydroxybutyrate in a simple cultivation set-up with dissolved oxygen as the single controlled parameter. Approximately 98% of the obtained PHB was formed from CO2.
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Affiliation(s)
- Vera Lambauer
- Austrian Centre of Industrial Biotechnology (ACIB), Krenngasse 37, A-8010 Graz, Austria;
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/II, A-8010 Graz, Austria
| | - Regina Kratzer
- Austrian Centre of Industrial Biotechnology (ACIB), Krenngasse 37, A-8010 Graz, Austria;
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/II, A-8010 Graz, Austria
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Strittmatter CS, Eggers J, Biesgen V, Pauels I, Becker F, Steinbüchel A. The reliance of glycerol utilization by Cupriavidus necator on CO 2 fixation and improved glycerol catabolism. Appl Microbiol Biotechnol 2022; 106:2541-2555. [PMID: 35325274 DOI: 10.1007/s00253-022-11842-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 11/29/2022]
Abstract
While crude glycerol is a cheap carbon source for industrial-scale cultivation of microorganisms, its application relies on fast growth and conversion. The biopolymer producing Cupriavidus necator H16 (synonym: Ralstonia eutropha H16) grows poorly on glycerol. The heterologous expression of glycerol facilitator glpF, glycerol kinase glpK, and glycerol dehydrogenase glpD from E. coli accelerated the growth considerably. The naturally occurring glycerol utilization is inhibited by low glycerol kinase activity. A limited heterotrophic growth promotes the dependency on autotrophic growth by carbon dioxide (CO2) fixation and refixation. As mixotrophic growth occurs in the wildtype due to low consumption rates of glycerol, CO2 fixation by the Calvin-Benson-Bassham (CBB) cycle is essential. The deletion of both cbbX copies encoding putative RuBisCO-activases (AAA + ATPase) resulted in a sharp slowdown of growth and glycerol consumption. Activase activity is necessary for functioning carboxylation by RuBisCO. Each of the two copies compensates for the loss of the other, as suggested by observed expression levels. The strong tendency towards autotrophy supports previous investigations of glycerol growth and emphasizes the versatility of the metabolism of C. necator H16. Mixotrophy with glycerol-utilization and CO2 fixation with a high dependence on the CBB is automatically occurring unless transportation and degradation of glycerol are optimized. Parallel engineering of CO2 fixation and glycerol degradation is suggested towards application for value-added production from crude glycerol. KEY POINTS: • Growth on glycerol is highly dependent on efficient carbon fixation via CBB cycle. • CbbX is essential for the efficiency of RuBisCO in C. necator H16. • Expression of glycerol degradation pathway enzymes accelerates glycerol utilization.
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Affiliation(s)
- Carl Simon Strittmatter
- Insitut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universtität Münster, Münster, Germany
| | - Jessica Eggers
- Insitut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universtität Münster, Münster, Germany
| | - Vanessa Biesgen
- Insitut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universtität Münster, Münster, Germany
| | - Inga Pauels
- Insitut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universtität Münster, Münster, Germany
| | - Florian Becker
- Insitut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universtität Münster, Münster, Germany
| | - Alexander Steinbüchel
- Insitut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universtität Münster, Münster, Germany. .,Environmental Science Department, King Abdulaziz University, Jeddah, Saudi Arabia.
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Improved polyhydroxybutyrate production by Cupriavidus necator and the photocatalyst graphitic carbon nitride from fructose under low light intensity. Int J Biol Macromol 2022; 203:526-534. [PMID: 35120931 DOI: 10.1016/j.ijbiomac.2022.01.179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/26/2022] [Accepted: 01/28/2022] [Indexed: 11/21/2022]
Abstract
The photocatalyst graphitic carbon nitride (g-C3N4) is known to photostimulate the production of the bioplastic polyhydroxybutyrate (PHB) by Cupriavidus necator. In previous studies, the combination of C. necator and g-C3N4 increased PHB yield from either an organic or inorganic carbon substrate under a light intensity of 4200 lx. Here, different parameters including light intensity, pH, temperature, nitrogen and carbon concentrations, aeration, and inoculum size were explored to maximize PHB production by hybrid photosynthesis from fructose and visible light. A g-C3N4/C. necator culture grown with a lower light intensity of 2100 lx, an inoculum size of 128.30 × 106 CFU ml-1, and constant aeration produced 7.16 g l-1 d-1 PHB with a product yield from fructose of 60.94%. Furthermore, the ratio of incident photons harvested by g-C3N4 converted into NADPH+H+ by C. necator for PHB production was improved to 19.74% after the process optimization. In comparison, the PHB production rate of a non-optimized g-C3N4/C. necator system exposed to 4200 lx was only 2.94 g l-1 d-1 with a product yield from fructose of 33.29%. These results demonstrate that hybrid photosynthesis productivity can be significantly augmented by decreasing light intensity and adjusting other parameters, which is promising for future bioproduction applications.
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Loss of mobile genomic islands in metal resistant, hydrogen-oxidizing Cupriavidus metallidurans. Appl Environ Microbiol 2021; 88:e0204821. [PMID: 34910578 DOI: 10.1128/aem.02048-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genome of the metal resistant, hydrogen-oxidizing bacterium Cupriavidus metallidurans strain CH34 contains horizontally acquired plasmids and genomic islands. Metal-resistance determinants on the two plasmids may exert genetic dominance over other related determinants. To investigate whether these recessive determinants can be activated in the absence of the dominant ones, the transcriptome of the highly zinc-sensitive deletion mutant Δe4 (ΔcadA ΔzntA ΔdmeF ΔfieF) of the plasmid-free parent AE104 was characterized using gene arrays. As a consequence of some unexpected results, close examination by PCR and genomic re-resequencing of strains CH34, AE104, Δe4 and others revealed that the genomic islands CMGIs 2, 3, 4, D, E, but no other islands or recessive determinants, were deleted in some of these strains. Provided CH34 wild type was kept under alternating zinc and nickel selection pressure, no comparable deletions occurred. All current data suggest that genes were actually deleted and were not, as previously surmised, simply absent from the respective strain. As a consequence, a cured database was compiled from the newly generated and previously published gene array data. Analysis of data from this database indicated that some genes of recessive, no longer needed determinants were nevertheless expressed and up-regulated. Their products may interact with those of the dominant determinants to mediate a mosaic phenotype. The ability to contribute to such a mosaic phenotype may prevent deletion of the recessive determinant. The data suggest that the bacterium actively modifies its genome to deal with metal stress and the same time ensures metal homeostasis. Significance In their natural environment, bacteria continually acquire genes by horizontal gene transfer and newly acquired determinants may become dominant over related ones already present in the host genome. When a bacterium is taken into laboratory culture, it is isolated from the horizontal gene transfer network. It can no longer gain genes, but instead may lose them. This was indeed observed in Cupriavidus metallidurans for loss key metal-resistance determinants when no selection pressure was continuously kept. However, some recessive metal-resistance determinants were maintained in the genome. It is proposed that they might contribute some accessory genes to related dominant resistance determinants, for instance periplasmic metal-binding proteins or two-component regulatory systems. Alternatively, they may only remain in the genome because their DNA serves as a scaffold for the nucleoid. Using C. metallidurans as an example, this study sheds light on the fate and function of horizontally acquired genes in bacteria.
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Exploiting Aerobic Carboxydotrophic Bacteria for Industrial Biotechnology. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2021; 180:1-32. [PMID: 34894287 DOI: 10.1007/10_2021_178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Aerobic carboxydotrophic bacteria are a group of microorganisms which possess the unique trait to oxidize carbon monoxide (CO) as sole energy source with molecular oxygen (O2) to produce carbon dioxide (CO2) which subsequently is used for biomass formation via the Calvin-Benson-Bassham cycle. Moreover, most carboxydotrophs are also able to oxidize hydrogen (H2) with hydrogenases to drive the reduction of carbon dioxide in the absence of CO. As several abundant industrial off-gases contain significant amounts of CO, CO2, H2 as well as O2, these bacteria come into focus for industrial application to produce chemicals and fuels from such gases in gas fermentation approaches. Since the group of carboxydotrophic bacteria is rather unknown and not very well investigated, we will provide an overview about their lifestyle and the underlying metabolic characteristics, introduce promising members for industrial application, and give an overview of available genetic engineering tools. We will point to limitations and discuss challenges, which have to be overcome to apply metabolic engineering approaches and to utilize aerobic carboxydotrophs in the industrial environment.
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Fan Q, Neubauer P, Gimpel M. Production of soluble regulatory hydrogenase from Ralstonia eutropha in Escherichia coli using a fed-batch-based autoinduction system. Microb Cell Fact 2021; 20:201. [PMID: 34663324 PMCID: PMC8522226 DOI: 10.1186/s12934-021-01690-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/27/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Autoinduction systems can regulate protein production in Escherichia coli without the need to monitor cell growth or add inducer at the proper time following culture growth. Compared to classical IPTG induction, autoinduction provides a simple and fast way to obtain high protein yields. In the present study, we report on the optimization process for the enhanced heterologous production of the Ralstonia eutropha regulatory hydrogenase (RH) in E. coli using autoinduction. These autoinduction methods were combined with the EnPresso B fed-batch like growth system, which applies slow in situ enzymatic glucose release from a polymer to control cell growth and protein synthesis rate. RESULTS We were able to produce 125 mg L-1 RH corresponding to a productivity averaged over the whole process time of 3 mg (L h)-1 in shake flasks using classic single-shot IPTG induction. IPTG autoinduction resulted in a comparable volumetric RH yield of 112 mg L-1 and due to the shorter overall process time in a 1.6-fold higher productivity of 5 mg (L h)-1. In contrast, lactose autoinduction increased the volumetric yield more than 2.5-fold and the space time yield fourfold reaching 280 mg L-1 and 11.5 mg (L h)-1, respectively. Furthermore, repeated addition of booster increased RH production to 370 mg L-1, which to our knowledge is the highest RH concentration produced in E. coli to date. CONCLUSIONS The findings of this study confirm the general feasibility of the developed fed-batch based autoinduction system and provide an alternative to conventional induction systems for efficient recombinant protein production. We believe that the fed-batch based autoinduction system developed herein will favor the heterologous production of larger quantities of difficult-to-express complex enzymes to enable economical production of these kinds of proteins.
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Affiliation(s)
- Qin Fan
- Chair of Bioprocess Engineering, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Peter Neubauer
- Chair of Bioprocess Engineering, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Matthias Gimpel
- Chair of Bioprocess Engineering, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
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Electron inventory of the iron-sulfur scaffold complex HypCD essential in [NiFe]-hydrogenase cofactor assembly. Biochem J 2021; 478:3281-3295. [PMID: 34409988 PMCID: PMC8454700 DOI: 10.1042/bcj20210224] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 11/17/2022]
Abstract
The [4Fe-4S] cluster containing scaffold complex HypCD is the central construction site for the assembly of the [Fe](CN)2CO cofactor precursor of [NiFe]-hydrogenase. While the importance of the HypCD complex is well established, not much is known about the mechanism by which the CN- and CO ligands are transferred and attached to the iron ion. We report an efficient expression and purification system producing the HypCD complex from E. coli with complete metal content. This enabled in-depth spectroscopic characterizations. The results obtained by EPR and Mössbauer spectroscopy demonstrate that the [Fe](CN)2CO cofactor and the [4Fe-4S] cluster of the HypCD complex are redox active. The data indicate a potential-dependent interconversion of the [Fe]2+/3+ and [4Fe-4S]2+/+ couple, respectively. Moreover, ATR FTIR spectroscopy reveals potential-dependent disulfide formation, which hints at an electron confurcation step between the metal centers. MicroScale thermophoresis indicates preferable binding between the HypCD complex and its in vivo interaction partner HypE under reducing conditions. Together, these results provide comprehensive evidence for an electron inventory fit to drive multi-electron redox reactions required for the assembly of the CN- and CO ligands on the scaffold complex HypCD.
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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: 63] [Impact Index Per Article: 21.0] [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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Li Z, Xin X, Xiong B, Zhao D, Zhang X, Bi C. Engineering the Calvin-Benson-Bassham cycle and hydrogen utilization pathway of Ralstonia eutropha for improved autotrophic growth and polyhydroxybutyrate production. Microb Cell Fact 2020; 19:228. [PMID: 33308236 PMCID: PMC7733298 DOI: 10.1186/s12934-020-01494-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 12/05/2020] [Indexed: 12/24/2022] Open
Abstract
Background CO2 is fixed by all living organisms with an autotrophic metabolism, among which the Calvin–Benson–Bassham (CBB) cycle is the most important and widespread carbon fixation pathway. Thus, studying and engineering the CBB cycle with the associated energy providing pathways to increase the CO2 fixation efficiency of cells is an important subject of biological research with significant application potential. Results In this work, the autotrophic microbe Ralstonia eutropha (Cupriavidus necator) was selected as a research platform for CBB cycle optimization engineering. By knocking out either CBB operon genes on the operon or mega-plasmid of R. eutropha, we found that both CBB operons were active and contributed almost equally to the carbon fixation process. With similar knock-out experiments, we found both soluble and membrane-bound hydrogenases (SH and MBH), belonging to the energy providing hydrogenase module, were functional during autotrophic growth of R. eutropha. SH played a more significant role. By introducing a heterologous cyanobacterial RuBisCO with the endogenous GroES/EL chaperone system(A quality control systems for proteins consisting of molecular chaperones and proteases, which prevent protein aggregation by either refolding or degrading misfolded proteins) and RbcX(A chaperone in the folding of Rubisco), the culture OD600 of engineered strain increased 89.2% after 72 h of autotrophic growth, although the difference was decreased at 96 h, indicating cyanobacterial RuBisCO with a higher activity was functional in R. eutropha and lead to improved growth in comparison to the host specific enzyme. Meanwhile, expression of hydrogenases was optimized by modulating the expression of MBH and SH, which could further increase the R. eutropha H16 culture OD600 to 93.4% at 72 h. Moreover, the autotrophic yield of its major industrially relevant product, polyhydroxybutyrate (PHB), was increased by 99.7%. Conclusions To our best knowledge, this is the first report of successfully engineering the CBB pathway and hydrogenases of R. eutropha for improved activity, and is one of only a few cases where the efficiency of CO2 assimilation pathway was improved. Our work demonstrates that R. eutropha is a useful platform for studying and engineering the CBB for applications.
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Affiliation(s)
- Zhongkang Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Xiuqing Xin
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Bin Xiong
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Dongdong Zhao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Xueli Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
| | - Changhao Bi
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
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Tang R, Weng C, Peng X, Han Y. Metabolic engineering of Cupriavidus necator H16 for improved chemoautotrophic growth and PHB production under oxygen-limiting conditions. Metab Eng 2020; 61:11-23. [DOI: 10.1016/j.ymben.2020.04.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/21/2020] [Accepted: 04/16/2020] [Indexed: 01/03/2023]
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18
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Fan Q, Neubauer P, Lenz O, Gimpel M. Heterologous Hydrogenase Overproduction Systems for Biotechnology-An Overview. Int J Mol Sci 2020; 21:E5890. [PMID: 32824336 PMCID: PMC7460606 DOI: 10.3390/ijms21165890] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/06/2020] [Accepted: 08/14/2020] [Indexed: 01/16/2023] Open
Abstract
Hydrogenases are complex metalloenzymes, showing tremendous potential as H2-converting redox catalysts for application in light-driven H2 production, enzymatic fuel cells and H2-driven cofactor regeneration. They catalyze the reversible oxidation of hydrogen into protons and electrons. The apo-enzymes are not active unless they are modified by a complicated post-translational maturation process that is responsible for the assembly and incorporation of the complex metal center. The catalytic center is usually easily inactivated by oxidation, and the separation and purification of the active protein is challenging. The understanding of the catalytic mechanisms progresses slowly, since the purification of the enzymes from their native hosts is often difficult, and in some case impossible. Over the past decades, only a limited number of studies report the homologous or heterologous production of high yields of hydrogenase. In this review, we emphasize recent discoveries that have greatly improved our understanding of microbial hydrogenases. We compare various heterologous hydrogenase production systems as well as in vitro hydrogenase maturation systems and discuss their perspectives for enhanced biohydrogen production. Additionally, activities of hydrogenases isolated from either recombinant organisms or in vivo/in vitro maturation approaches were systematically compared, and future perspectives for this research area are discussed.
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Affiliation(s)
- Qin Fan
- Institute of Biotechnology, Technical University of Berlin, Ackerstraße 76, 13355 Berlin, Germany; (Q.F.); (P.N.)
| | - Peter Neubauer
- Institute of Biotechnology, Technical University of Berlin, Ackerstraße 76, 13355 Berlin, Germany; (Q.F.); (P.N.)
| | - Oliver Lenz
- Department of Chemistry, Technical University of Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany;
| | - Matthias Gimpel
- Institute of Biotechnology, Technical University of Berlin, Ackerstraße 76, 13355 Berlin, Germany; (Q.F.); (P.N.)
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Preissler J, Reeve HA, Zhu T, Nicholson J, Urata K, Lauterbach L, Wong LL, Vincent KA, Lenz O. Dihydrogen‐Driven NADPH Recycling in Imine Reduction and P450‐Catalyzed Oxidations Mediated by an Engineered O
2
‐Tolerant Hydrogenase. ChemCatChem 2020. [DOI: 10.1002/cctc.202000763] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Janina Preissler
- Institute of Chemistry, Biophysical Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
| | - Holly A. Reeve
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Tianze Zhu
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Jake Nicholson
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Kouji Urata
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Lars Lauterbach
- Institute of Chemistry, Biophysical Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
| | - Luet L. Wong
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Kylie A. Vincent
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Oliver Lenz
- Institute of Chemistry, Biophysical Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
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Al-Shameri A, Willot SJP, Paul CE, Hollmann F, Lauterbach L. H 2 as a fuel for flavin- and H 2O 2-dependent biocatalytic reactions. Chem Commun (Camb) 2020; 56:9667-9670. [PMID: 32696786 DOI: 10.1039/d0cc03229h] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The soluble hydrogenase from Ralstonia eutropha provides an atom efficient regeneration system for reduced flavin cofactors using H2 as an electron source. We demonstrated this system for highly selective ene-reductase-catalyzed C[double bond, length as m-dash]C-double bond reductions and monooxygenase-catalyzed epoxidation. Reactions were expanded to aerobic conditions to supply H2O2 for peroxygenase-catalyzed hydroxylations.
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Affiliation(s)
- Ammar Al-Shameri
- Institute of Chemistry, Technische Universität Berlin, Strasse des 17, Juni 135, 10623 Berlin, Germany.
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21
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Hydrogen Production from Methane by Methylomonas sp. DH-1 under Micro-aerobic Conditions. BIOTECHNOL BIOPROC E 2020. [DOI: 10.1007/s12257-019-0256-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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22
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Isegawa M, Matsumoto T, Ogo S. Selective Oxidation of H 2 and CO by NiIr Catalyst in Aqueous Solution: A DFT Mechanistic Study. Inorg Chem 2020; 59:1014-1028. [PMID: 31898897 DOI: 10.1021/acs.inorgchem.9b02400] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
One of the challenges in utilizing hydrogen gas (H2) as a sustainable fossil fuel alternative is the inhibition of H2 oxidation by carbon monoxide (CO), which is involved in the industrial production of H2 sources. To solve this problem, a catalyst that selectively oxidizes either CO or H2 or one that co-oxidizes H2 and CO is needed. Recently, a NiIr catalyst [NiIICl(X)IrIIICl(η5-C5Me5)], (X = N,N'-dimethyl-3,7-diazanonane-1,9-dithiolate), which efficiently and selectively oxidizes either H2 or CO depending on the pH, has been developed (Angew. Chem. Int. Ed. 2017, 56, 9723-9726). In the present work, density functional theory (DFT) calculations are employed to elucidate the pH-dependent reaction mechanisms of H2 and CO oxidation catalyzed by this NiIr catalyst. During H2 oxidation, our calculations suggest that dihydrogen binds to the Ir center and generates an Ir(III)-dihydrogen complex, followed by subsequent isomerization to an Ir(V)-dihydride species. Then, a proton is abstracted by a buffer base, CH3COO-, resulting in the formation of a hydride complex. The catalytic cycle completes with electron transfer from the hydride complex to a protonated 2,6-dichlorobenzeneindophenol (DCIP) and a proton transfer from the oxidized hydride complex to a buffer base. The CO oxidation mechanism involves three distinct steps, i.e., (1) formation of a metal carbonyl complex, (2) formation of a metallocarboxylic acid, and (3) conversion of the metallocarboxylic acid to a hydride complex. The formation of the metallocarboxylic acid involves nucleophilic attack of OH- to the carbonyl-C followed by a large structural change with concomitant cleavage of the Ir-S bond and rotation of the COOH group along the NiIr axis. During the conversion of the metallocarboxylic acid to the hydride complex, intramolecular proton transfer followed by removal of CO2 leads to the formation of the hydride complexes. In addition, the barrier heights for the binding of small molecules (H2, OH-, H2O, and CO) to Ir were calculated, and the results indicated that dissociation from Ir is a faster process than the binding of H2O and H2. These calculations indicate that H2 oxidation is inhibited by CO and OH- and thus prefers acidic conditions. In contrast, the CO oxidation reactions occur more favorably under basic conditions, as the formation of the metallocarboxylic acid involves OH- attack to a carbonyl-C and the binding of OH- to Ni largely stabilizes the triplet spin state of the complex. Taken together, these calculations provide a rationale for the experimentally observed pH-dependent, selective oxidations of H2 and CO.
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Affiliation(s)
- Miho Isegawa
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Takahiro Matsumoto
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Seiji Ogo
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
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Yu J, Lu Y. Carbon dioxide fixation by a hydrogen-oxidizing bacterium: Biomass yield, reversal respiratory quotient, stoichiometric equations and bioenergetics. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.107369] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Albina P, Durban N, Bertron A, Albrecht A, Robinet JC, Erable B. Influence of Hydrogen Electron Donor, Alkaline pH, and High Nitrate Concentrations on Microbial Denitrification: A Review. Int J Mol Sci 2019; 20:ijms20205163. [PMID: 31635215 PMCID: PMC6834205 DOI: 10.3390/ijms20205163] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/02/2019] [Accepted: 10/15/2019] [Indexed: 12/25/2022] Open
Abstract
Bacterial respiration of nitrate is a natural process of nitrate reduction, which has been industrialized to treat anthropic nitrate pollution. This process, also known as “microbial denitrification”, is widely documented from the fundamental and engineering points of view for the enhancement of the removal of nitrate in wastewater. For this purpose, experiments are generally conducted with heterotrophic microbial metabolism, neutral pH and moderate nitrate concentrations (<50 mM). The present review focuses on a different approach as it aims to understand the effects of hydrogenotrophy, alkaline pH and high nitrate concentration on microbial denitrification. Hydrogen has a high energy content but its low solubility, 0.74 mM (1 atm, 30 °C), in aqueous medium limits its bioavailability, putting it at a kinetic disadvantage compared to more soluble organic compounds. For most bacteria, the optimal pH varies between 7.5 and 9.5. Outside this range, denitrification is slowed down and nitrite (NO2−) accumulates. Some alkaliphilic bacteria are able to express denitrifying activity at pH levels close to 12 thanks to specific adaptation and resistance mechanisms detailed in this manuscript, and some bacterial populations support nitrate concentrations in the range of several hundred mM to 1 M. A high concentration of nitrate generally leads to an accumulation of nitrite. Nitrite accumulation can inhibit bacterial activity and may be a cause of cell death.
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Affiliation(s)
- Pierre Albina
- Laboratoire Matériaux et Durabilité des Constructions, Université de Toulouse, UPS, INSA. 135, 7 avenue de Rangueil, 31077 Toulouse CEDEX 04, France.
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31030 Toulouse, France.
| | - Nadège Durban
- Laboratoire Matériaux et Durabilité des Constructions, Université de Toulouse, UPS, INSA. 135, 7 avenue de Rangueil, 31077 Toulouse CEDEX 04, France.
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31030 Toulouse, France.
| | - Alexandra Bertron
- Laboratoire Matériaux et Durabilité des Constructions, Université de Toulouse, UPS, INSA. 135, 7 avenue de Rangueil, 31077 Toulouse CEDEX 04, France.
| | - Achim Albrecht
- Andra (Agence nationale pour la gestion des déchets radioactifs), 92298 Châtenay-Malabry, France.
| | - Jean-Charles Robinet
- Andra (Agence nationale pour la gestion des déchets radioactifs), 92298 Châtenay-Malabry, France.
| | - Benjamin Erable
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31030 Toulouse, France.
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Grenz S, Baumann PT, Rückert C, Nebel BA, Siebert D, Schwentner A, Eikmanns BJ, Hauer B, Kalinowski J, Takors R, Blombach B. Exploiting Hydrogenophaga pseudoflava for aerobic syngas-based production of chemicals. Metab Eng 2019; 55:220-230. [PMID: 31319152 DOI: 10.1016/j.ymben.2019.07.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/25/2019] [Accepted: 07/12/2019] [Indexed: 01/04/2023]
Abstract
Gasification is a suitable technology to generate energy-rich synthesis gas (syngas) from biomass or waste streams, which can be utilized in bacterial fermentation processes for the production of chemicals and fuels. Established microbial processes currently rely on acetogenic bacteria which perform an energetically inefficient anaerobic CO oxidation and acetogenesis potentially hampering the biosynthesis of complex and ATP-intensive products. Since aerobic oxidation of CO is energetically more favorable, we exploit in this study the Gram-negative β-proteobacterium Hydrogenophaga pseudoflava DSM1084 as novel host for the production of chemicals from syngas. We sequenced and annotated the genome of H. pseudoflava and established a genetic engineering toolbox, which allows markerless chromosomal modification via the pk19mobsacB system and heterologous gene expression on pBBRMCS2-based plasmids. The toolbox was extended by identifying strong endogenous promotors such as PgapA2 which proved to yield high expression under heterotrophic and autotrophic conditions. H. pseudoflava showed relatively fast heterotrophic growth in complex and minimal medium with sugars and organic acids which allows convenient handling in lab routines. In autotrophic bioreactor cultivations with syngas, H. pseudoflava exhibited a growth rate of 0.06 h-1 and biomass specific uptakes rates of 14.2 ± 0.3 mmol H2 gCDW-1 h-1, 73.9 ± 1.8 mmol CO gCDW-1 h-1, and 31.4 ± 0.3 mmol O2 gCDW-1 h-1. As proof of concept, we engineered the carboxydotrophic bacterium for the aerobic production of the C15 sesquiterpene (E)-α-bisabolene from the C1 carbon source syngas by heterologous expression of the (E)-α-bisabolene synthase gene agBIS. The resulting strain H. pseudoflava (pOCEx1:agBIS) produced 59 ± 8 μg (E)-α-bisabolene L-1 with a volumetric productivity Qp of 1.2 ± 0.2 μg L-1 h-1 and a biomass-specific productivity qp of 13.1 ± 0.6 μg gCDW-1 h-1. The intrinsic properties and the genetic repertoire of H. pseudoflava make this carboxydotrophic bacterium a promising candidate for future aerobic production processes to synthesize more complex or ATP-intensive chemicals from syngas.
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Affiliation(s)
- Sebastian Grenz
- Institute of Biochemical Engineering, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Philipp T Baumann
- Institute of Biochemical Engineering, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Christian Rückert
- Center for Biotechnology, Bielefeld University, Universitätsstraße 27, 33615, Bielefeld, Germany
| | - Bernd A Nebel
- Department of Technical Biochemistry, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Daniel Siebert
- Institute of Microbiology and Biotechnology, University of Ulm, 89069, Ulm, Germany; Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Straubing, Germany
| | - Andreas Schwentner
- Institute of Microbiology and Biotechnology, University of Ulm, 89069, Ulm, Germany
| | - Bernhard J Eikmanns
- Institute of Microbiology and Biotechnology, University of Ulm, 89069, Ulm, Germany
| | - Bernhard Hauer
- Department of Technical Biochemistry, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Jörn Kalinowski
- Center for Biotechnology, Bielefeld University, Universitätsstraße 27, 33615, Bielefeld, Germany
| | - Ralf Takors
- Institute of Biochemical Engineering, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Bastian Blombach
- Institute of Biochemical Engineering, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany; Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Straubing, Germany.
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Inactivation of the uptake hydrogenase in the purple non-sulfur photosynthetic bacterium Rubrivivax gelatinosus CBS enables a biological water–gas shift platform for H2 production. ACTA ACUST UNITED AC 2019; 46:993-1002. [DOI: 10.1007/s10295-019-02173-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 04/03/2019] [Indexed: 10/27/2022]
Abstract
Abstract
Biological H2 production has potential to address energy security and environmental concerns if produced from renewable or waste sources. The purple non-sulfur photosynthetic bacterium Rubrivivax gelatinosus CBS produces H2 while oxidizing CO, a component of synthesis gas (Syngas). CO-linked H2 production is facilitated by an energy-converting hydrogenase (Ech), while a subsequent H2 oxidation reaction is catalyzed by a membrane-bound hydrogenase (MBH). Both hydrogenases contain [NiFe] active sites requiring 6 maturation factors (HypA-F) for assembly, but it is unclear which of the two annotated sets of hyp genes are required for each in R. gelatinosus CBS. Herein, we report correlated expression of hyp1 genes with Ech genes and hyp2 expression with MBH genes. Moreover, we find that while Ech H2 evolving activity is only delayed when hyp1 is deleted, hyp2 deletion completely disrupts MBH H2 uptake, providing a platform for a biologically driven water–gas shift reaction to produce H2 from CO.
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Qiu S, Li Q, Xu Y, Shen S, Sun C. Learning from nature: Understanding hydrogenase enzyme using computational approach. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1422] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Siyao Qiu
- Science & Technology Innovation Institute Dongguan University of Technology Dongguan China
| | - Qinye Li
- School of Chemical Engineering Monash University Clayton Victoria Australia
| | - Yongjun Xu
- Science & Technology Innovation Institute Dongguan University of Technology Dongguan China
| | - Shaohua Shen
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Shaanxi China
| | - Chenghua Sun
- Department of Chemistry and Biotechnology, and Center for Translational Atomaterials Swinburne University of Technology Hawthorn Victoria Australia
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New insights into Fe–H$$_{2}$$ and Fe–H$$^{-}$$ bonding of a [NiFe] hydrogenase mimic: a local vibrational mode study. Theor Chem Acc 2019. [DOI: 10.1007/s00214-019-2463-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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29
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Abstract
The availability of renewable energy technologies is increasing dramatically across the globe thanks to their growing maturity. However, large scale electrical energy storage and retrieval will almost certainly be a required in order to raise the penetration of renewable sources into the grid. No present energy storage technology has the perfect combination of high power and energy density, low financial and environmental cost, lack of site restrictions, long cycle and calendar lifespan, easy materials availability, and fast response time. Engineered electroactive microbes could address many of the limitations of current energy storage technologies by enabling rewired carbon fixation, a process that spatially separates reactions that are normally carried out together in a photosynthetic cell and replaces the least efficient with non-biological equivalents. If successful, this could allow storage of renewable electricity through electrochemical or enzymatic fixation of carbon dioxide and subsequent storage as carbon-based energy storage molecules including hydrocarbons and non-volatile polymers at high efficiency. In this article we compile performance data on biological and non-biological component choices for rewired carbon fixation systems and identify pressing research and engineering challenges.
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Piché-Choquette S, Constant P. Molecular Hydrogen, a Neglected Key Driver of Soil Biogeochemical Processes. Appl Environ Microbiol 2019; 85:e02418-18. [PMID: 30658976 PMCID: PMC6414374 DOI: 10.1128/aem.02418-18] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The atmosphere of the early Earth is hypothesized to have been rich in reducing gases such as hydrogen (H2). H2 has been proposed as the first electron donor leading to ATP synthesis due to its ubiquity throughout the biosphere as well as its ability to easily diffuse through microbial cells and its low activation energy requirement. Even today, hydrogenase enzymes enabling the production and oxidation of H2 are found in thousands of genomes spanning the three domains of life across aquatic, terrestrial, and even host-associated ecosystems. Even though H2 has already been proposed as a universal growth and maintenance energy source, its potential contribution as a driver of biogeochemical cycles has received little attention. Here, we bridge this knowledge gap by providing an overview of the classification, distribution, and physiological role of hydrogenases. Distribution of these enzymes in various microbial functional groups and recent experimental evidence are finally integrated to support the hypothesis that H2-oxidizing microbes are keystone species driving C cycling along O2 concentration gradients found in H2-rich soil ecosystems. In conclusion, we suggest focusing on the metabolic flexibility of H2-oxidizing microbes by combining community-level and individual-level approaches aiming to decipher the impact of H2 on C cycling and the C-cycling potential of H2-oxidizing microbes, via both culture-dependent and culture-independent methods, to give us more insight into the role of H2 as a driver of biogeochemical processes.
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Qiu S, Azofra LM, Macfarlane DR, Sun C. Hydrogen Evolution in [NiFe] Hydrogenases: A Case of Heterolytic Approach between Proton and Hydride. Inorg Chem 2019; 58:2979-2986. [DOI: 10.1021/acs.inorgchem.8b02812] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Siyao Qiu
- Science & Technology Innovation Institute, Dongguan University of Technology, Dongguan 523808, China
- School of Chemistry, Faculty of Science, Monash University, Clayton, VIC 3800, Australia
| | - Luis Miguel Azofra
- KAUST Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Douglas R. Macfarlane
- School of Chemistry, Faculty of Science, Monash University, Clayton, VIC 3800, Australia
- ARC Centre of Excellence for Electromaterials Science (ACES), School of Chemistry, Faculty of Science, Monash University, Clayton, VIC 3800, Australia
| | - Chenghua Sun
- Science & Technology Innovation Institute, Dongguan University of Technology, Dongguan 523808, China
- Department of Chemistry and Biotechnology, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
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Perspectives for the biotechnological production of biofuels from CO2 and H2 using Ralstonia eutropha and other ‘Knallgas’ bacteria. Appl Microbiol Biotechnol 2019; 103:2113-2120. [DOI: 10.1007/s00253-019-09636-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 01/03/2023]
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33
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Yu J. Fixation of carbon dioxide by a hydrogen-oxidizing bacterium for value-added products. World J Microbiol Biotechnol 2018; 34:89. [PMID: 29886519 DOI: 10.1007/s11274-018-2473-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 06/04/2018] [Indexed: 01/03/2023]
Abstract
With rapid technology progress and cost reduction, clean hydrogen from water electrolysis driven by renewable powers becomes a potential feedstock for CO2 fixation by hydrogen-oxidizing bacteria. Cupriavidus necator (formally Ralstonia eutropha), a representative member of the lithoautotrophic prokaryotes, is a promising producer of polyhydroxyalkanoates and single cell proteins. This paper reviews the fundamental properties of the hydrogen-oxidizing bacterium, the metabolic activities under limitation of individual gases and nutrients, and the value-added products from CO2, including the products with large potential markets. Gas fermentation and bioreactor safety are discussed for achieving high cell density and high productivity of desired products under chemolithotrophic conditions. The review also updates the recent research activities in metabolic engineering of C. necator to produce novel metabolites from CO2.
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Affiliation(s)
- Jian Yu
- Hawaii Natural Energy Institute, University of Hawaii at Manoa, Honolulu, USA.
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34
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Gutekunst K. Hypothesis on the Synchronistic Evolution of Autotrophy and Heterotrophy. Trends Biochem Sci 2018; 43:402-411. [DOI: 10.1016/j.tibs.2018.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 03/05/2018] [Accepted: 03/20/2018] [Indexed: 10/17/2022]
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35
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Solvent production by engineered Ralstonia eutropha: channeling carbon to biofuel. Appl Microbiol Biotechnol 2018; 102:5021-5031. [DOI: 10.1007/s00253-018-9026-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/12/2018] [Accepted: 04/14/2018] [Indexed: 12/11/2022]
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36
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Qiu S, Azofra LM, MacFarlane DR, Sun C. Hydrogen bonding effect between active site and protein environment on catalysis performance in H 2-producing [NiFe] hydrogenases. Phys Chem Chem Phys 2018; 20:6735-6743. [PMID: 29457815 DOI: 10.1039/c7cp07685a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The interaction between the active site and the surrounding protein environment plays a fundamental role in the hydrogen evolution reaction (HER) in [NiFe] hydrogenases. Our density functional theory (DFT) findings demonstrate that the reaction Gibbs free energy required for the rate determining step decreases by 7.1 kcal mol-1 when the surrounding protein environment is taken into account, which is chiefly due to free energy decreases for the two H+/e- addition steps (the so-called Ni-SIa to I1, and Ni-C to Ni-R), being the largest thermodynamic impediments of the whole reaction. The variety of hydrogen bonds (H-bonds) between the amino acids and the active site is hypothesised to be the main reason for such stability: H-bonds not only work as electrostatic attractive forces that influence the charge redistribution, but more importantly, they act as an electron 'pull' taking electrons from the active site towards the amino acids. Moreover, the electron 'pull' effect through H-bonds via the S- in cysteine residues shows a larger influence on the energy profile than that via the CN- ligands on Fe.
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Affiliation(s)
- Siyao Qiu
- School of Chemistry, Faculty of Science, Monash University, Clayton, VIC 3800, Australia.
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Rewiring of Cyanobacterial Metabolism for Hydrogen Production: Synthetic Biology Approaches and Challenges. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1080:171-213. [PMID: 30091096 DOI: 10.1007/978-981-13-0854-3_8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
With the demand for renewable energy growing, hydrogen (H2) is becoming an attractive energy carrier. Developing H2 production technologies with near-net zero carbon emissions is a major challenge for the "H2 economy." Certain cyanobacteria inherently possess enzymes, nitrogenases, and bidirectional hydrogenases that are capable of H2 evolution using sunlight, making them ideal cell factories for photocatalytic conversion of water to H2. With the advances in synthetic biology, cyanobacteria are currently being developed as a "plug and play" chassis to produce H2. This chapter describes the metabolic pathways involved and the theoretical limits to cyanobacterial H2 production and summarizes the metabolic engineering technologies pursued.
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38
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Qiu S, Olsen S, MacFarlane DR, Sun C. The oxygen reduction reaction on [NiFe] hydrogenases. Phys Chem Chem Phys 2018; 20:23528-23534. [DOI: 10.1039/c8cp04160a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Oxygen tolerance capacity is critical for hydrogen oxidation/evolution catalysts.
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Affiliation(s)
- Siyao Qiu
- Science & Technology Innovation Institute
- Dongguan University of Technology
- Dongguan
- China
- School of Chemistry
| | - Seth Olsen
- School of Chemistry
- Faculty of Science
- Monash University
- Clayton
- VIC 3800
| | | | - Chenghua Sun
- Science & Technology Innovation Institute
- Dongguan University of Technology
- Dongguan
- China
- Department of Chemistry and Biotechnology
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39
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Evans RM, Beaton SE. A novel overproduction system for the structural determination of a proton-pumping hydrogen-producing [NiFe]-hydrogenase. Methods Enzymol 2018; 613:91-116. [DOI: 10.1016/bs.mie.2018.10.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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40
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Campbell BJ, Sessions AL, Fox DN, Paul BG, Qin Q, Kellermann MY, Valentine DL. Minimal Influence of [NiFe] Hydrogenase on Hydrogen Isotope Fractionation in H 2-Oxidizing Cupriavidus necator. Front Microbiol 2017; 8:1886. [PMID: 29085342 PMCID: PMC5649130 DOI: 10.3389/fmicb.2017.01886] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 09/14/2017] [Indexed: 11/25/2022] Open
Abstract
Fatty acids produced by H2-metabolizing bacteria are sometimes observed to be more D-depleted than those of photoautotrophic organisms, a trait that has been suggested as diagnostic for chemoautotrophic bacteria. The biochemical reasons for such a depletion are not known, but are often assumed to involve the strong D-depletion of H2. Here, we cultivated the bacterium Cupriavidus necator H16 (formerly Ralstonia eutropha H16) under aerobic, H2-consuming, chemoautotrophic conditions and measured the isotopic compositions of its fatty acids. In parallel with the wild type, two mutants of this strain, each lacking one of two key hydrogenase enzymes, were also grown and measured. In all three strains, fractionations between fatty acids and water ranged from -173‰ to -235‰, and averaged -217‰, -196‰, and -226‰, respectively, for the wild type, SH- mutant, and MBH- mutant. There was a modest increase in δD as a result of loss of the soluble hydrogenase enzyme. Fractionation curves for all three strains were constructed by growing parallel cultures in waters with δDwater values of approximately -25‰, 520‰, and 1100‰. These curves indicate that at least 90% of the hydrogen in fatty acids is derived from water, not H2. Published details of the biochemistry of the soluble and membrane-bound hydrogenases confirm that these enzymes transfer electrons rather than intact hydride (H-) ions, providing no direct mechanism to connect the isotopic composition of H2 to that of lipids. Multiple lines of evidence thus agree that in this organism, and presumably others like it, environmental H2 plays little or no direct role in controlling lipid δD values. The observed fractionations must instead result from isotope effects in the reduction of NAD(P)H by reductases with flavin prosthetic groups, which transfer two electrons and acquire H+ (or D+) from solution. Parallels to NADPH reduction in photosynthesis may explain why D/H fractionations in C. necator are nearly identical to those in many photoautotrophic algae and bacteria. We conclude that strong D-depletion is not a diagnostic feature of chemoautotrophy.
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Affiliation(s)
- Brian J Campbell
- Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Alex L Sessions
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United States
| | - Daniel N Fox
- Undergraduate College of Letters and Sciences, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Blair G Paul
- Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Qianhui Qin
- Interdepartmental Graduate Program in Marine Science, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Matthias Y Kellermann
- Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University, Wilhelmshaven, Germany
| | - David L Valentine
- Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA, United States.,Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
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41
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Heinrich D, Raberg M, Steinbüchel A. Studies on the aerobic utilization of synthesis gas (syngas) by wild type and recombinant strains of Ralstonia eutropha H16. Microb Biotechnol 2017; 11:647-656. [PMID: 29027357 PMCID: PMC6011924 DOI: 10.1111/1751-7915.12873] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 01/11/2023] Open
Abstract
The biotechnical platform strain Ralstonia eutropha H16 was genetically engineered to express a cox subcluster of the carboxydotrophic Oligotropha carboxidovoransOM5, including (i) the structural genes coxM, -S and -L, coding for an aerobic carbon monoxide dehydrogenase (CODH) and (ii) the genes coxD, -E, -F and -G, essential for the maturation of CODH. The coxOc genes expressed under control of the CO2 -inducible promoter PL enabled R. eutropha to oxidize CO to CO2 for the use as carbon source, as demonstrated by 13 CO experiments, but the recombinant strains remained dependent on H2 as external energy supply. Therefore, a synthetic metabolism, which could be described as 'carboxyhydrogenotrophic', was established in R. eutropha. With this extension of the bacterium's substrate range, growth in CO-, H2 - and CO2 -containing artificial synthesis gas atmosphere was enhanced, and poly(3-hydroxybutyrate) synthesis was increased by more than 20%.
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Affiliation(s)
- Daniel Heinrich
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - Matthias Raberg
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - Alexander Steinbüchel
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität, Münster, Germany.,Environmental Sciences Department, King Abdulaziz University, Jeddah, Saudi Arabia
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42
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Yan B, Concannon NM, Milshtein JD, Brushett FR, Surendranath Y. A Membrane‐Free Neutral pH Formate Fuel Cell Enabled by a Selective Nickel Sulfide Oxygen Reduction Catalyst. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201702578] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Bing Yan
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Nolan M. Concannon
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Jarrod D. Milshtein
- Department of Materials Science and Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Fikile R. Brushett
- Department of Chemical Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Yogesh Surendranath
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
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43
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Yan B, Concannon NM, Milshtein JD, Brushett FR, Surendranath Y. A Membrane‐Free Neutral pH Formate Fuel Cell Enabled by a Selective Nickel Sulfide Oxygen Reduction Catalyst. Angew Chem Int Ed Engl 2017; 56:7496-7499. [DOI: 10.1002/anie.201702578] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Indexed: 11/07/2022]
Affiliation(s)
- Bing Yan
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Nolan M. Concannon
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Jarrod D. Milshtein
- Department of Materials Science and Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Fikile R. Brushett
- Department of Chemical Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
| | - Yogesh Surendranath
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave. Cambridge MA 02139-4307 USA
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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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Tejwani V, Schmitt FJ, Wilkening S, Zebger I, Horch M, Lenz O, Friedrich T. Investigation of the NADH/NAD + ratio in Ralstonia eutropha using the fluorescence reporter protein Peredox. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1858:86-94. [PMID: 27816420 DOI: 10.1016/j.bbabio.2016.11.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/11/2016] [Accepted: 11/02/2016] [Indexed: 10/20/2022]
Abstract
Ralstonia eutropha is a hydrogen-oxidizing ("Knallgas") bacterium that can easily switch between heterotrophic and autotrophic metabolism to thrive in aerobic and anaerobic environments. Its versatile metabolism makes R. eutropha an attractive host for biotechnological applications, including H2-driven production of biodegradable polymers and hydrocarbons. H2 oxidation by R. eutropha takes place in the presence of O2 and is mediated by four hydrogenases, which represent ideal model systems for both biohydrogen production and H2 utilization. The so-called soluble hydrogenase (SH) couples reversibly H2 oxidation with the reduction of NAD+ to NADH and has already been applied successfully in vitro and in vivo for cofactor regeneration. Thus, the interaction of the SH with the cellular NADH/NAD+ pool is of major interest. In this work, we applied the fluorescent biosensor Peredox to measure the [NADH]:[NAD+] ratio in R. eutropha cells under different metabolic conditions. The results suggest that the sensor operates close to saturation level, indicating a rather high [NADH]:[NAD+] ratio in aerobically grown R. eutropha cells. Furthermore, we demonstrate that multicomponent analysis of spectrally-resolved fluorescence lifetime data of the Peredox sensor response to different [NADH]:[NAD+] ratios represents a novel and sensitive tool to determine the redox state of cells.
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Affiliation(s)
- Vijay Tejwani
- SUNY Polytechnic Institute, College of Nanoscale Science and Engineering, 257 Fuller Road, Albany, NY, 12203, U.S.A
| | - Franz-Josef Schmitt
- Technische Universität Berlin, Institut für Chemie, PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany
| | - Svea Wilkening
- Technische Universität Berlin, Institut für Chemie, PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany
| | - Ingo Zebger
- Technische Universität Berlin, Institut für Chemie, PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany
| | - Marius Horch
- Technische Universität Berlin, Institut für Chemie, PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany
| | - Oliver Lenz
- Technische Universität Berlin, Institut für Chemie, PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany
| | - Thomas Friedrich
- Technische Universität Berlin, Institut für Chemie, PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany.
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Nowroth V, Marquart L, Jendrossek D. Low temperature-induced viable but not culturable state of Ralstonia eutropha and its relationship to accumulated polyhydroxybutyrate. FEMS Microbiol Lett 2016; 363:fnw249. [PMID: 27810883 PMCID: PMC5175184 DOI: 10.1093/femsle/fnw249] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/26/2016] [Accepted: 10/29/2016] [Indexed: 12/25/2022] Open
Abstract
The culturability of Escherichia coli, Ralstonia eutropha and Bacillus subtilis after incubation in phosphate-buffered saline at either 5°C or 30°C was determined. The culturability of B. subtilis showed little dependence on temperature. The culturability of E. coli rapidly decreased at 30°C but remained almost constant at 5°C. In contrast, the culturability of R. eutropha decreased by three orders of magnitude at 5°C within 24 h but only moderately decreased (one order of magnitude) at 30°C. Remarkably, prolonged incubation of R. eutropha at 30°C resulted in a full recovery of colony forming units in contrast to only a partial recovery at 5°C. Ralstonia eutropha cells at 30°C remained culturable for 3 weeks while culturability at 5°C constantly decreased. The effect of temperature was significantly stronger in a polyhydroxybutyrate-negative mutant. Our data show that accumulated polyhydroxybutyrate has a cold-protective function and can prevent R. eutropha entering the viable but not culturable state.
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Affiliation(s)
- Verena Nowroth
- Institute of Microbiology, University of Stuttgart, 70550 Stuttgart, Germany
| | - Lisa Marquart
- Institute of Microbiology, University of Stuttgart, 70550 Stuttgart, Germany
| | - Dieter Jendrossek
- Institute of Microbiology, University of Stuttgart, 70550 Stuttgart, Germany
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47
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Jugder BE, Welch J, Braidy N, Marquis CP. Construction and use of a Cupriavidus necator H16 soluble hydrogenase promoter (PSH) fusion to gfp (green fluorescent protein). PeerJ 2016; 4:e2269. [PMID: 27547572 PMCID: PMC4974937 DOI: 10.7717/peerj.2269] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 06/28/2016] [Indexed: 12/30/2022] Open
Abstract
Hydrogenases are metalloenzymes that reversibly catalyse the oxidation or production of molecular hydrogen (H2). Amongst a number of promising candidates for application in the oxidation of H2 is a soluble [Ni–Fe] uptake hydrogenase (SH) produced by Cupriavidus necator H16. In the present study, molecular characterisation of the SH operon, responsible for functional SH synthesis, was investigated by developing a green fluorescent protein (GFP) reporter system to characterise PSH promoter activity using several gene cloning approaches. A PSH promoter-gfp fusion was successfully constructed and inducible GFP expression driven by the PSH promoter under de-repressing conditions in heterotrophic growth media was demonstrated in the recombinant C. necator H16 cells. Here we report the first successful fluorescent reporter system to study PSH promoter activity in C. necator H16. The fusion construct allowed for the design of a simple screening assay to evaluate PSH activity. Furthermore, the constructed reporter system can serve as a model to develop a rapid fluorescent based reporter for subsequent small-scale process optimisation experiments for SH expression.
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Affiliation(s)
- Bat-Erdene Jugder
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Jeffrey Welch
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Nady Braidy
- Centre for Health Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW, Australia
| | - Christopher P Marquis
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
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48
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Qiu S, Azofra LM, MacFarlane DR, Sun C. Unraveling the Role of Ligands in the Hydrogen Evolution Mechanism Catalyzed by [NiFe] Hydrogenases. ACS Catal 2016. [DOI: 10.1021/acscatal.6b01359] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Siyao Qiu
- School
of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Luis Miguel Azofra
- School
of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
- ARC
Centre of Excellence for Electromaterials Science (ACES), School of
Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Douglas R. MacFarlane
- School
of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
- ARC
Centre of Excellence for Electromaterials Science (ACES), School of
Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Chenghua Sun
- School
of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
- ARC
Centre of Excellence for Electromaterials Science (ACES), School of
Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
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49
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Abstract
In Escherichia coli, hydrogen metabolism plays a prominent role in anaerobic physiology. The genome contains the capability to produce and assemble up to four [NiFe]-hydrogenases, each of which are known, or predicted, to contribute to different aspects of cellular metabolism. In recent years, there have been major advances in the understanding of the structure, function, and roles of the E. coli [NiFe]-hydrogenases. The membrane-bound, periplasmically oriented, respiratory Hyd-1 isoenzyme has become one of the most important paradigm systems for understanding an important class of oxygen-tolerant enzymes, as well as providing key information on the mechanism of hydrogen activation per se. The membrane-bound, periplasmically oriented, Hyd-2 isoenzyme has emerged as an unusual, bidirectional redox valve able to link hydrogen oxidation to quinone reduction during anaerobic respiration, or to allow disposal of excess reducing equivalents as hydrogen gas. The membrane-bound, cytoplasmically oriented, Hyd-3 isoenzyme is part of the formate hydrogenlyase complex, which acts to detoxify excess formic acid under anaerobic fermentative conditions and is geared towards hydrogen production under those conditions. Sequence identity between some Hyd-3 subunits and those of the respiratory NADH dehydrogenases has led to hypotheses that the activity of this isoenzyme may be tightly coupled to the formation of transmembrane ion gradients. Finally, the E. coli genome encodes a homologue of Hyd-3, termed Hyd-4, however strong evidence for a physiological role for E. coli Hyd-4 remains elusive. In this review, the versatile hydrogen metabolism of E. coli will be discussed and the roles and potential applications of the spectrum of different types of [NiFe]-hydrogenases available will be explored.
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50
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Hugenbruch S, Shafaat HS, Krämer T, Delgado-Jaime MU, Weber K, Neese F, Lubitz W, DeBeer S. In search of metal hydrides: an X-ray absorption and emission study of [NiFe] hydrogenase model complexes. Phys Chem Chem Phys 2016; 18:10688-99. [DOI: 10.1039/c5cp07293j] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Insight into the factors that favor metal–hydride interactions in NiFe-hydrogenase models is obtained through X-ray spectroscopic and quantum chemical studies.
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Affiliation(s)
| | - Hannah S. Shafaat
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
- The Ohio State University
- Department of Chemistry and Biochemistry
| | - Tobias Krämer
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
- Heriot-Watt University
- Institute of Chemical Sciences
| | - Mario Ulises Delgado-Jaime
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
- Inorganic Chemistry and Catalysis Group
- Debye Institute for Nanomaterials Science
| | - Katharina Weber
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion
- D-45470
- Germany
- Cornell University
- Department of Chemistry and Chemical Biology
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