1
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Babayan A, Vassilian A, Poladyan A, Trchounian K. Role of the Escherichia coli FocA and FocB formate channels in controlling proton/potassium fluxes and hydrogen production during osmotic stress in energy-limited, stationary phase fermenting cells. Biochimie 2024; 221:91-98. [PMID: 38307245 DOI: 10.1016/j.biochi.2024.01.017] [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: 10/30/2023] [Revised: 01/12/2024] [Accepted: 01/30/2024] [Indexed: 02/04/2024]
Abstract
Escherichia coli FocA and FocB formate channels export formate or import it for further disproportionation by the formate hydrogenlyase (FHL) complex to H2 and CO2. Here, we show that under pH and osmotic stress FocA and FocB play important roles in regulating proton and potassium fluxes and couple this with H2 production in stationary-phase cells. Using whole-cell assays with glucose as electron donor, a focB mutant showed a 50 % decrease in VH2, while N'N'-dicyclohexylcarbodiimide (DCCD) treatment of osmotically stressed cells underlined the role of FOF1 ATPase in H2 production. At pH 7.5 and under osmotic stress FocB contributed to the proton flux but not to the potassium flux. At pH 5.5 both formate channels contributed to the proton and potassium fluxes. Particulalry, a focA mutant had 40 % lower potassium flux whereas the proton flux increased approximately two-fold. Moreover, at pH 5.5H2 production was totally inhibited by DCCD in the focA mutant. Taken together, our results suggest that depending on external pH, the formate channels play an important role in osmoregulation by helping to balance proton/potassium fluxes and H2 production, and thus assist the proton FOF1-ATPase in maintenance of ion gradients in fermenting stationary-phase cells.
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Affiliation(s)
- A Babayan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025, Yerevan, Armenia; Research Institute of Biology, Yerevan State University, 0025, Yerevan, Armenia
| | - A Vassilian
- Research Institute of Biology, Yerevan State University, 0025, Yerevan, Armenia.
| | - A Poladyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025, Yerevan, Armenia; Research Institute of Biology, Yerevan State University, 0025, Yerevan, Armenia.
| | - K Trchounian
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025, Yerevan, Armenia; Research Institute of Biology, Yerevan State University, 0025, Yerevan, Armenia; Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025, Yerevan, Armenia.
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2
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Kammel M, Erdmann C, Sawers RG. The formate-hydrogen axis and its impact on the physiology of enterobacterial fermentation. Adv Microb Physiol 2024; 84:51-82. [PMID: 38821634 DOI: 10.1016/bs.ampbs.2024.02.002] [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] [Indexed: 06/02/2024]
Abstract
Formic acid (HCOOH) and dihydrogen (H2) are characteristic products of enterobacterial mixed-acid fermentation, with H2 generation increasing in conjunction with a decrease in extracellular pH. Formate and acetyl-CoA are generated by radical-based and coenzyme A-dependent cleavage of pyruvate catalysed by pyruvate formate-lyase (PflB). Formate is also the source of H2, which is generated along with carbon dioxide through the action of the membrane-associated, cytoplasmically-oriented formate hydrogenlyase (FHL-1) complex. Synthesis of the FHL-1 complex is completely dependent on the cytoplasmic accumulation of formate. Consequently, formate determines its own disproportionation into H2 and CO2 by the FHL-1 complex. Cytoplasmic formate levels are controlled by FocA, a pentameric channel that translocates formic acid/formate bidirectionally between the cytoplasm and periplasm. Each protomer of FocA has a narrow hydrophobic pore through which neutral formic acid can pass. Two conserved amino acid residues, a histidine and a threonine, at the center of the pore control directionality of translocation. The histidine residue is essential for pH-dependent influx of formic acid. Studies with the formate analogue hypophosphite and amino acid variants of FocA suggest that the mechanisms of formic acid efflux and influx differ. Indeed, current data suggest, depending on extracellular formate levels, two separate uptake mechanisms exist, both likely contributing to maintain pH homeostasis. Bidirectional formate/formic acid translocation is dependent on PflB and influx requires an active FHL-1 complex. This review describes the coupling of formate and H2 production in enterobacteria.
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Affiliation(s)
- Michelle Kammel
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle, Saale, Germany
| | - Christopher Erdmann
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle, Saale, Germany
| | - R Gary Sawers
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle, Saale, Germany.
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3
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Manutsyan T, Blbulyan S, Vassilian A, Semashko T, Kirakosyan G, Gabrielyan L, Trchounian K, Poladyan A. Gold nanoparticles activate hydrogenase synthesis and improve heterotrophic growth of Ralstonia eutropha H16. FEMS Microbiol Lett 2024; 371:fnad138. [PMID: 38167703 DOI: 10.1093/femsle/fnad138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 10/17/2023] [Accepted: 12/31/2023] [Indexed: 01/05/2024] Open
Abstract
Ralstonia eutropha is a facultative chemolithoautotrophic aerobic bacterium that grows using organic substrates or H2 and CO2. Hydrogenases (Hyds) are synthesized under lithoautotrophic, or energy-limited heterotrophic conditions and are used in enzyme fuel cells (EFC) as anodic catalysts. The effects of chemically synthesized gold nanoparticles (Au-NPs) on R. eutropha H16 growth, oxidation-reduction potential (ORP) kinetics, and H2-oxidizing Hyd activity were investigated in this study. Atomic force microscopy showed that thin, plate-shaped Au-NPs were in the nanoscale range with an average size of 5.68 nm. Compared with growth in medium without Au-NPs (control), the presence of Au-NPs stimulated growth, and resulted in a decrease in ORP to negative values. H2-oxidizing activity was not detected in the absence of Au-NPs, but activity was significantly induced (12 U/g CDW) after 24 h of growth with 18 ng/ml, increasing a further 4-fold after 72 h of growth. The results demonstrate that Au-NPs primarily influence the membrane-bound Hyd. In contrast to R. eutropha, Au-NPs had a negligible or negative effect on the growth, Hyd activity, and H2 production of Escherichia coli. The findings of this study offer new perspectives for the production of oxygen-tolerant Hyds and the development of EFCs.
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Affiliation(s)
- Tatevik Manutsyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025 Yerevan, Armenia
| | - Syuzanna Blbulyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025 Yerevan, Armenia
| | - Anait Vassilian
- Research Institute of Biology, Biology Faculty, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia
| | | | | | - Lilit Gabrielyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025 Yerevan, Armenia
| | - Karen Trchounian
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025 Yerevan, Armenia
- Research Institute of Biology, Biology Faculty, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia
| | - Anna Poladyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 0025 Yerevan, Armenia
- Research Institute of Biology, Biology Faculty, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia
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4
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Kurt E, Qin J, Williams A, Zhao Y, Xie D. Perspectives for Using CO 2 as a Feedstock for Biomanufacturing of Fuels and Chemicals. Bioengineering (Basel) 2023; 10:1357. [PMID: 38135948 PMCID: PMC10740661 DOI: 10.3390/bioengineering10121357] [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: 10/17/2023] [Revised: 11/20/2023] [Accepted: 11/24/2023] [Indexed: 12/24/2023] Open
Abstract
Microbial cell factories offer an eco-friendly alternative for transforming raw materials into commercially valuable products because of their reduced carbon impact compared to conventional industrial procedures. These systems often depend on lignocellulosic feedstocks, mainly pentose and hexose sugars. One major hurdle when utilizing these sugars, especially glucose, is balancing carbon allocation to satisfy energy, cofactor, and other essential component needs for cellular proliferation while maintaining a robust yield. Nearly half or more of this carbon is inevitably lost as CO2 during the biosynthesis of regular metabolic necessities. This loss lowers the production yield and compromises the benefit of reducing greenhouse gas emissions-a fundamental advantage of biomanufacturing. This review paper posits the perspectives of using CO2 from the atmosphere, industrial wastes, or the exhausted gases generated in microbial fermentation as a feedstock for biomanufacturing. Achieving the carbon-neutral or -negative goals is addressed under two main strategies. The one-step strategy uses novel metabolic pathway design and engineering approaches to directly fix the CO2 toward the synthesis of the desired products. Due to the limitation of the yield and efficiency in one-step fixation, the two-step strategy aims to integrate firstly the electrochemical conversion of the exhausted CO2 into C1/C2 products such as formate, methanol, acetate, and ethanol, and a second fermentation process to utilize the CO2-derived C1/C2 chemicals or co-utilize C5/C6 sugars and C1/C2 chemicals for product formation. The potential and challenges of using CO2 as a feedstock for future biomanufacturing of fuels and chemicals are also discussed.
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Affiliation(s)
- Elif Kurt
- Department of Chemical Engineering, University of Massachusetts, Lowell, MA 01854, USA; (E.K.); (J.Q.); (A.W.)
| | - Jiansong Qin
- Department of Chemical Engineering, University of Massachusetts, Lowell, MA 01854, USA; (E.K.); (J.Q.); (A.W.)
| | - Alexandria Williams
- Department of Chemical Engineering, University of Massachusetts, Lowell, MA 01854, USA; (E.K.); (J.Q.); (A.W.)
| | - Youbo Zhao
- Physical Sciences Inc., 20 New England Business Ctr., Andover, MA 01810, USA;
| | - Dongming Xie
- Department of Chemical Engineering, University of Massachusetts, Lowell, MA 01854, USA; (E.K.); (J.Q.); (A.W.)
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5
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Fasano A, Guendon C, Jacq-Bailly A, Kpebe A, Wozniak J, Baffert C, Barrio MD, Fourmond V, Brugna M, Léger C. A Chimeric NiFe Hydrogenase Heterodimer to Assess the Role of the Electron Transfer Chain in Tuning the Enzyme's Catalytic Bias and Oxygen Tolerance. J Am Chem Soc 2023; 145:20021-20030. [PMID: 37657413 DOI: 10.1021/jacs.3c06895] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
The observation that some homologous enzymes have the same active site but very different catalytic properties demonstrates the importance of long-range effects in enzyme catalysis, but these effects are often difficult to rationalize. The NiFe hydrogenases 1 and 2 (Hyd 1 and Hyd 2) from E. coli both consist of a large catalytic subunit that embeds the same dinuclear active site and a small electron-transfer subunit with a chain of three FeS clusters. Hyd 1 is mostly active in H2 oxidation and resistant to inhibitors, whereas Hyd 2 also catalyzes H2 production and is strongly inhibited by O2 and CO. Based on structural and site-directed mutagenesis data, it is currently believed that the catalytic bias and tolerance to O2 of Hyd 1 are defined by the distal and proximal FeS clusters, respectively. To test these hypotheses, we produced and characterized a hybrid enzyme made of the catalytic subunit of Hyd 1 and the electron transfer subunit of Hyd 2. We conclude that catalytic bias and sensitivity to CO are set by the catalytic subunit rather than by the electron transfer chain. We confirm the importance of the proximal cluster in making the enzyme Hyd 1 resist long-term exposure to O2, but we show that other structural determinants, in both subunits, contribute to O2 tolerance. A similar strategy based on the design of chimeric heterodimers could be used in the future to elucidate various structure-function relationships in hydrogenases and other multimeric metalloenzymes and to engineer useful hydrogenases that combine the desirable properties of distinct, homologous enzymes.
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Affiliation(s)
- Andrea Fasano
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Chloé Guendon
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Aurore Jacq-Bailly
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Arlette Kpebe
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Jérémy Wozniak
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Carole Baffert
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Melisa Del Barrio
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
- Department of Analytical Chemistry, Faculty of Chemistry, Complutense University of Madrid, 28040 Madrid, Spain
| | - Vincent Fourmond
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Myriam Brugna
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
| | - Christophe Léger
- Laboratoire de Bioénergétique et Ingénierie des Protéines, CNRS, Aix Marseille Université, UMR 7281, Marseille, France
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6
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Nguyen HK, Minato T, Moniruzzaman M, Kiyasu Y, Ogo S, Yoon KS. Selective formate production from H 2 and CO 2 using encapsulated whole-cells under mild reaction conditions. J Biosci Bioeng 2023; 136:182-189. [PMID: 37400329 DOI: 10.1016/j.jbiosc.2023.06.002] [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: 02/14/2023] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 07/05/2023]
Abstract
Biocatalytic CO2 reduction into formate is a crucial strategy for developing clean energy because formate is considered as one of the promising hydrogen storage materials for achieving net-zero carbon emissions. Here, we developed an efficient biocatalytic system to produce formate selectively by coupling two enzymatic activities of H2 oxidation and CO2 reduction using encapsulated bacterial cells of Citrobacter sp. S-77. The encapsulated whole-cell catalyst was made by living cells depositing into polyvinyl alcohol and gellan gum cross-linked by calcium ions to form hydrogel beads. Formate production using encapsulated cells was carried out under the resting state conditions in the gas mixture of H2/CO2 (70:30, v/v%). The whole-cell biocatalyst showed highly efficient and selective catalytic production of formate, reaching the specific rate of formate production of 110 mmol L-1· gprotein-1·h-1 at 30 °C, pH 7.0, and 0.1 MPa. The encapsulated cells can be reused at least 8 times while keeping their high catalytic activities for formate production under mild reaction conditions.
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Affiliation(s)
- Hung Khac Nguyen
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Japan
| | - Takuo Minato
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Japan; International Institute for Carbon-Neutral Energy Research (WPI-I(2)CNER), Kyushu University, Japan; Department of Applied Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8527, Japan
| | - Mohammad Moniruzzaman
- International Institute for Carbon-Neutral Energy Research (WPI-I(2)CNER), Kyushu University, Japan; Mitsui Chemicals, Inc.- Carbon Neutral Research Center (MCI-CNRC), Kyushu University, Japan
| | - Yu Kiyasu
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Japan
| | - Seiji Ogo
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Japan; International Institute for Carbon-Neutral Energy Research (WPI-I(2)CNER), Kyushu University, Japan; Center for Small Molecule Energy, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Ki-Seok Yoon
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Japan; International Institute for Carbon-Neutral Energy Research (WPI-I(2)CNER), Kyushu University, Japan; Mitsui Chemicals, Inc.- Carbon Neutral Research Center (MCI-CNRC), Kyushu University, Japan.
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7
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Poladyan A, Trchounian K, Paloyan A, Minasyan E, Aghekyan H, Iskandaryan M, Khoyetsyan L, Aghayan S, Tsaturyan A, Antranikian G. Valorization of whey-based side streams for microbial biomass, molecular hydrogen, and hydrogenase production. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12609-x. [PMID: 37289241 DOI: 10.1007/s00253-023-12609-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/09/2023]
Abstract
Side streams of the dairy industry are a suitable nutrient source for cultivating microorganisms, producing enzymes, and high-value chemical compounds. The heterotrophic Escherichia coli and chemolithoautotroph Ralstonia eutropha are of major biotechnological interest. R. eutropha is a model organism for producing O2-tolerant [NiFe]-hydrogenases (Hyds) (biocatalysts), and E. coli has found widespread use as an expression platform for producing recombinant proteins, molecular hydrogen (H2), and other valuable products. Aiming at developing suitable cultivation media from side streams of the dairy industry, the pre-treatment (filtration, dilution, and pH adjustment) of cheese (sweet) whey (SW) and curd (acid) whey (AW), with and without the use of ß-glucosidase, has been performed. Growth parameters (oxidation-reduction potential (ORP), pH changes, specific growth rate, biomass formation) of E. coli BW25113 and R. eutropha H16 type strains were monitored during cultivation on filtered and non-filtered SW and AW at 37 °C, pH 7.5 and 30 °C, pH 7.0, respectively. Along with microbial growth, measurements of pH and ORP indicated good fermentative growth. Compared to growth on fructose-nitrogen minimal salt medium (control), a maximum cell yield (OD600 4.0) and H2-oxidizing Hyd activity were achieved in the stationary growth phase for R. eutropha. Hyd-3-dependent H2 production by E. coli utilizing whey as a growth substrate was demonstrated. Moreover, good biomass production and prolonged H2 yields of ~ 5 mmol/L and cumulative H2 ~ 94 mL g/L dry whey (DW) (ß-glucosidase-treated) were observed during the cultivation of the engineered E. coli strain. These results open new avenues for effective whey treatment using thermostable β-glucosidase and confirm whey as an economically viable commodity for biomass and biocatalyst production. KEY POINTS: • Archaeal thermostable β-glucosidase isolated from the metagenome of a hydrothermal spring was used for lactose hydrolysis in whey. • Hydrogenase enzyme activity was induced during the growth of Ralstonia eutropha H16 on whey. • Enhanced biomass and H2 production was shown in a genetically modified strain of Escherichia coli.
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Affiliation(s)
- Anna Poladyan
- Department of Biochemistry, Microbiology, and Biotechnology, Yerevan State University, Yerevan, Armenia, 1 A. Manoukian Str, 0025, Yerevan, Armenia.
- Research Institute of Biology, Biology Faculty, Yerevan State University, 0025, Yerevan, Armenia.
| | - Karen Trchounian
- Department of Biochemistry, Microbiology, and Biotechnology, Yerevan State University, Yerevan, Armenia, 1 A. Manoukian Str, 0025, Yerevan, Armenia
- Research Institute of Biology, Biology Faculty, Yerevan State University, 0025, Yerevan, Armenia
| | - Ani Paloyan
- SPC "Armbiotechnology" NAS RA, Yerevan, Armenia
| | - Ela Minasyan
- Institute of Pharmacy, Yerevan State University, 0025, Yerevan, Armenia
| | - Hayarpi Aghekyan
- Department of Biochemistry, Microbiology, and Biotechnology, Yerevan State University, Yerevan, Armenia, 1 A. Manoukian Str, 0025, Yerevan, Armenia
- Research Institute of Biology, Biology Faculty, Yerevan State University, 0025, Yerevan, Armenia
| | - Meri Iskandaryan
- Department of Biochemistry, Microbiology, and Biotechnology, Yerevan State University, Yerevan, Armenia, 1 A. Manoukian Str, 0025, Yerevan, Armenia
- Research Institute of Biology, Biology Faculty, Yerevan State University, 0025, Yerevan, Armenia
| | | | - Sargis Aghayan
- Research Institute of Biology, Biology Faculty, Yerevan State University, 0025, Yerevan, Armenia
| | - Avetis Tsaturyan
- SPC "Armbiotechnology" NAS RA, Yerevan, Armenia
- Institute of Pharmacy, Yerevan State University, 0025, Yerevan, Armenia
| | - Garabed Antranikian
- Hamburg University of Technology, Institute of Technical Biocatalysis, Hamburg, Germany
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8
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Jiang Q, Li T, Yang J, Aitchison CM, Huang J, Chen Y, Huang F, Wang Q, Cooper AI, Liu LN. Synthetic engineering of a new biocatalyst encapsulating [NiFe]-hydrogenases for enhanced hydrogen production. J Mater Chem B 2023; 11:2684-2692. [PMID: 36883480 PMCID: PMC10032307 DOI: 10.1039/d2tb02781j] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Hydrogenases are microbial metalloenzymes capable of catalyzing the reversible interconversion between molecular hydrogen and protons with high efficiency, and have great potential in the development of new electrocatalysts for renewable fuel production. Here, we engineered the intact proteinaceous shell of the carboxysome, a self-assembling protein organelle for CO2 fixation in cyanobacteria and proteobacteria, and sequestered heterologously produced [NiFe]-hydrogenases into the carboxysome shell. The protein-based hybrid catalyst produced in E. coli shows substantially improved hydrogen production under both aerobic and anaerobic conditions and enhanced material and functional robustness, compared to unencapsulated [NiFe]-hydrogenases. The catalytically functional nanoreactor as well as the self-assembling and encapsulation strategies provide a framework for engineering new bioinspired electrocatalysts to improve the sustainable production of fuels and chemicals in biotechnological and chemical applications.
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Affiliation(s)
- Qiuyao Jiang
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Tianpei Li
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China
| | - Jing Yang
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
- Materials Innovation Factory and Department of Chemistry, University of Liverpool, Liverpool L7 3NY, UK
| | - Catherine M Aitchison
- Materials Innovation Factory and Department of Chemistry, University of Liverpool, Liverpool L7 3NY, UK
| | - Jiafeng Huang
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Yu Chen
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Fang Huang
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Qiang Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475004, China
| | - Andrew I Cooper
- Materials Innovation Factory and Department of Chemistry, University of Liverpool, Liverpool L7 3NY, UK
| | - Lu-Ning Liu
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266003, China
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9
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Mozhiarasi V, Natarajan TS, Dhamodharan K. A high-value biohythane production: Feedstocks, reactor configurations, pathways, challenges, technoeconomics and applications. ENVIRONMENTAL RESEARCH 2023; 219:115094. [PMID: 36535394 DOI: 10.1016/j.envres.2022.115094] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
In recent years, the demand for high-quality biofuels from renewable sources has become an aspirational goal to offer a clean environment by alternating the depleting fossil fuels to meet future energy needs. In this aspect, biohythane production from wastes has received extensive research interest since it contains superior fuel characteristics than the promising conventional biofuel i.e. biogas. The main aim is to promote research and potentials of biohythane production by a systematic review of scientific literature on the biohythane production pathways, substrate/microbial consortium suitability, reactor design, and influential process/operational factors. Reactor configuration also decides the product yield in addition to other key factors like waste composition, temperature, pH, retention time and loading rates. Hence, a detailed emphasis on different reactor configurations with respect to the type of feedstock has also been given. The technical challenges are highlighted towards process optimization and system scale up. Meanwhile, solutions to improve product yield, technoeconomics, applications and key policy and governance factors to build a hydrogen based society have also been discussed.
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Affiliation(s)
- Velusamy Mozhiarasi
- CLRI Regional Centre, CSIR-Central Leather Research Institute (CSIR-CLRI), Jalandhar, 144 021, Punjab, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India.
| | - Thillai Sivakumar Natarajan
- Environmental Science Laboratory, CSIR-Central Leather Research Institute (CSIR-CLRI), Chennai, 600 020, Tamil Nadu, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Kondusamy Dhamodharan
- School of Energy and Environment, Thapar Institute of Engineering and Technology, Patiala, 147 004, Punjab, India
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10
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Conversion of Escherichia coli into Mixotrophic CO 2 Assimilation with Malate and Hydrogen Based on Recombinant Expression of 2-Oxoglutarate:Ferredoxin Oxidoreductase Using Adaptive Laboratory Evolution. Microorganisms 2023; 11:microorganisms11020253. [PMID: 36838218 PMCID: PMC9967407 DOI: 10.3390/microorganisms11020253] [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: 11/03/2022] [Revised: 01/04/2023] [Accepted: 01/13/2023] [Indexed: 01/21/2023] Open
Abstract
We report the mixotrophic growth of Escherichia coli based on recombinant 2-oxoglutarate:ferredoxin oxidoreductase (OGOR) to assimilate CO2 using malate as an auxiliary carbon source and hydrogen as an energy source. We employ a long-term (~184 days) two-stage adaptive evolution to convert heterotrophic E. coli into mixotrophic E. coli. In the first stage of evolution with serine, diauxic growth emerges as a prominent feature. At the end of the second stage of evolution with malate, the strain exhibits mixotrophy with CO2 as an essential substrate for growth. We expect this work will open new possibilities in the utilization of OGOR for microbial CO2 assimilation and future hydrogen-based electro-microbial conversion.
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11
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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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12
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Formate hydrogenlyase, formic acid translocation and hydrogen production: dynamic membrane biology during fermentation. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148919. [PMID: 36152681 DOI: 10.1016/j.bbabio.2022.148919] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/19/2022] [Accepted: 09/19/2022] [Indexed: 12/14/2022]
Abstract
Formate hydrogenlyase-1 (FHL-1) is a complex-I-like enzyme that is commonly found in gram-negative bacteria. The enzyme comprises a peripheral arm and a membrane arm but is not involved in quinone reduction. Instead, FHL-1 couples formate oxidation to the reduction of protons to molecular hydrogen (H2). Escherichia coli produces FHL-1 under fermentative conditions where it serves to detoxify formic acid in the environment. The membrane biology and bioenergetics surrounding E. coli FHL-1 have long held fascination. Here, we review recent work on understanding the molecular basis of formic acid efflux and influx. We also consider the structure and function of E. coli FHL-1, its relationship with formate transport, and pay particular attention to the molecular interface between the peripheral arm and the membrane arm. Finally, we highlight the interesting phenotype of genetic mutation of the ND1 Loop, which is located at that interface.
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13
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Schubert C, Unden G. Fumarate, a central electron acceptor for Enterobacteriaceae beyond fumarate respiration and energy conservation. Adv Microb Physiol 2023; 82:267-299. [PMID: 36948656 DOI: 10.1016/bs.ampbs.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
C4-dicarboxylates (C4-DCs) such as fumarate, l-malate and l-aspartate are key substrates for Enterobacteria such as Escherichia coli or Salmonella typhimurium during anaerobic growth. In general, C4-DCs are oxidants during biosynthesis, e.g., of pyrimidine or heme, acceptors for redox balancing, a high-quality nitrogen source (l-aspartate) and electron acceptor for fumarate respiration. Fumarate reduction is required for efficient colonization of the murine intestine, even though the colon contains only small amounts of C4-DCs. However, fumarate can be produced endogenously by central metabolism, allowing autonomous production of an electron acceptor for biosynthesis and redox balancing. Bacteria possess a complex set of transporters for the uptake (DctA), antiport (DcuA, DcuB, TtdT) and excretion (DcuC) of C4-DCs. DctA and DcuB exert regulatory functions and link transport to metabolic control through interaction with regulatory proteins. The sensor kinase DcuS of the C4-DC two-component system DcuS-DcuR forms complexes with DctA (aerobic) or DcuB (anaerobic), representing the functional state of the sensor. Moreover, EIIAGlc from the glucose phospho-transferase system binds to DctA and presumably inhibits C4-DC uptake. Overall, the function of fumarate as an oxidant in biosynthesis and redox balancing explains the pivotal role of fumarate reductase for intestinal colonization, while the role of fumarate in energy conservation (fumarate respiration) is of minor importance.
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Affiliation(s)
- Christopher Schubert
- Institute for Molecular Physiology (IMP), Microbiology and Biotechnology; Johannes Gutenberg-University, Mainz, Germany; Institute of Microbiology, ETH Zurich, Zurich, Switzerland.
| | - Gottfried Unden
- Institute for Molecular Physiology (IMP), Microbiology and Biotechnology; Johannes Gutenberg-University, Mainz, Germany.
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14
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Sebastiampillai S, Lacasse MJ, McCusker S, Campbell T, Nitz M, Zamble DB. Using a high-throughput, whole-cell hydrogenase assay to identify potential small molecule inhibitors of [NiFe]-hydrogenase. Metallomics 2022; 14:6747159. [DOI: 10.1093/mtomcs/mfac073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 08/29/2022] [Indexed: 11/06/2022]
Abstract
Abstract
[NiFe]-hydrogenases are used by several human pathogens to catalyze the reversible conversion between molecular hydrogen and protons and electrons. Hydrogenases provide an increased metabolic flexibility for pathogens, such as Escherichia coli and Helicobacter pylori, by allowing the use of molecular hydrogen as an energy source to promote survival in anaerobic environments. With the rise of antimicrobial resistance and the desire for novel therapeutics, the [NiFe]-hydrogenases are alluring targets. Inhibiting the nickel insertion pathway of [NiFe]-hydrogenases is attractive as this pathway is required for the generation of functional enzymes and is orthogonal to human biochemistry. In this work, nickel availability for the production and function of E. coli [NiFe]-hydrogenase was explored through immunoblot and activity assays. Whole-cell hydrogenase activities were assayed in high throughput against a small molecule library of known bioactives. Iodoquinol was identified as a potential inhibitor of the nickel biosynthetic pathway of [NiFe]-hydrogenase through a two-step screening process, but further studies with immunoblot assays showed confounding effects dependent on the cell growth phase. This study highlights the significance of considering the growth phenotype for whole-cell based assays overall and its effects on various cellular processes influenced by metal trafficking and homeostasis.
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Affiliation(s)
| | - Michael J Lacasse
- Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6 , Canada
| | - Susan McCusker
- Centre for Microbial Chemical Biology , MDCL-2330, Hamilton, Ontario L8S 4K1 , Canada
| | - Tracey Campbell
- Centre for Microbial Chemical Biology , MDCL-2330, Hamilton, Ontario L8S 4K1 , Canada
| | - Mark Nitz
- Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6 , Canada
| | - Deborah B Zamble
- Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6 , Canada
- Department of Biochemistry, University of Toronto , Toronto, Ontario M5S 1A8 , Canada
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15
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Shekhar C, Maeda T. Impaired glucose metabolism by deleting the operon of hydrogenase 2 in Escherichia coli. Arch Microbiol 2022; 204:627. [DOI: 10.1007/s00203-022-03245-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 08/23/2022] [Accepted: 09/08/2022] [Indexed: 11/25/2022]
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16
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Kammel M, Pinske C, Sawers RG. FocA and its central role in fine-tuning pH homeostasis of enterobacterial formate metabolism. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36197793 DOI: 10.1099/mic.0.001253] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
During enterobacterial mixed-acid fermentation, formate is generated from pyruvate by the glycyl-radical enzyme pyruvate formate-lyase (PflB). In Escherichia coli, especially at low pH, formate is then disproportionated to CO2 and H2 by the cytoplasmically oriented, membrane-associated formate hydrogenlyase (FHL) complex. If electron acceptors are available, however, formate is oxidized by periplasmically oriented, respiratory formate dehydrogenases. Formate translocation across the cytoplasmic membrane is controlled by the formate channel, FocA, a member of the formate-nitrite transporter (FNT) family of homopentameric anion channels. This review highlights recent advances in our understanding of how FocA helps to maintain intracellular formate and pH homeostasis during fermentation. Efflux and influx of formate/formic acid are distinct processes performed by FocA and both are controlled through protein interaction between FocA's N-terminal domain with PflB. Formic acid efflux by FocA helps to maintain cytoplasmic pH balance during exponential-phase growth. Uptake of formate against the electrochemical gradient (inside negative) is energetically and mechanistically challenging for a fermenting bacterium unless coupled with proton/cation symport. Translocation of formate/formic acid into the cytoplasm necessitates an active FHL complex, whose synthesis also depends on formate. Thus, FocA, FHL and PflB function together to govern formate homeostasis. We explain how FocA achieves efflux of formic acid and propose mechanisms for pH-dependent uptake of formate both with and without proton symport. We propose that FocA displays both channel- and transporter-like behaviour. Whether this translocation behaviour is shared by other members of the FNT family is also discussed.
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Affiliation(s)
- Michelle Kammel
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Constanze Pinske
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - R Gary Sawers
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
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17
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Soboh B, Adrian L, Stripp ST. An in vitro reconstitution system to monitor iron transfer to the active site during the maturation of [NiFe]-hydrogenase. J Biol Chem 2022; 298:102291. [PMID: 35868564 PMCID: PMC9418501 DOI: 10.1016/j.jbc.2022.102291] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/13/2022] [Accepted: 07/16/2022] [Indexed: 11/29/2022] Open
Abstract
[NiFe]-hydrogenases comprise a small and a large subunit. The latter harbors the biologically unique [NiFe](CN)2CO active site cofactor. The maturation process includes the assembly of the [Fe](CN)2CO cofactor precursor, nickel binding, endoproteolytic cleavage of the large subunit, and dimerization with the small subunit to yield active enzyme. The biosynthesis of the [Fe](CN)2CO moiety of [NiFe]-Hydrogenase 1 (Hyd-1) and Hyd-2 occurs on the scaffold complex HybG-HypD (GD), whereas the HypC-HypD complex (CD) is specific for the assembly of Hyd-3. The metabolic source and the route for delivering iron to the active site remain unclear. To investigate the maturation process of O2-tolerant Hyd-1 from Escherichia coli, we developed an enzymatic in vitro reconstitution system that allows for the synthesis of Hyd-1 using only purified components. Together with this in vitro reconstitution system, we employed biochemical analyses, infrared spectroscopy (ATR FTIR), mass spectrometry, and microscale thermophoresis (MST) to monitor the iron transfer during the maturation process and to understand how the [Fe](CN)2CO cofactor precursor is ultimately incorporated into the large subunit. We demonstrate the direct transfer of iron from 57Fe-labeled GD complex to the large subunit of Hyd-1. Our data reveal that the GD complex exclusively interacts with the large subunit of Hyd-1 and Hyd-2 but not with the large subunit of Hyd-3. Furthermore, we show that the presence of iron in the active site is a prerequisite for nickel insertion. Taken together, these findings reveal how the [Fe](CN)2CO cofactor precursor is transferred and incorporated into the active site of [NiFe]-hydrogenase.
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Affiliation(s)
- Basem Soboh
- Genetic Biophysics, Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany.
| | - Lorenz Adrian
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Permoserstraße 15, 04318 Leipzig, Germany; Chair of Geobiotechnology, Technische Universität Berlin, Ackerstraße 76, 13355 Berlin, Germany
| | - Sven T Stripp
- Experimental Molecular Biophysics, Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
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18
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Katsyv A, Müller V. A purified energy-converting hydrogenase from Thermoanaerobacter kivui demonstrates coupled H +-translocation and reduction in vitro. J Biol Chem 2022; 298:102216. [PMID: 35779632 PMCID: PMC9356269 DOI: 10.1016/j.jbc.2022.102216] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 12/04/2022] Open
Abstract
Energy-converting hydrogenases (Ech) are ancient, membrane-bound enzymes that use reduced ferredoxin (Fd) as an electron donor to reduce protons to molecular H2. Experiments with whole cells, membranes and vesicle-fractions suggest that proton reduction is coupled to proton translocation across the cytoplasmatic membrane, but this has never been demonstrated with a purified enzyme. To this end, we produced a His-tagged Ech complex in the thermophilic and anaerobic bacterium Thermoanaerobacter kivui. The enzyme could be purified by affinity chromatography from solubilized membranes with full retention of its eight subunits, as well as full retention of physiological activities, i.e., H2-dependent Fd reduction and Fd2--dependent H2 production. We found the purified enzyme contained 34.2 ± 12.2 mol of iron/mol of protein, in accordance with seven predicted [4Fe-4S]-clusters and one [Ni-Fe]-center. The pH and temperature optima were at 7 to 8 and 66 °C, respectively. Notably, we found that the enzymatic activity was inhibited by N,N′-dicyclohexylcarbodiimide, an agent known to bind ion-translocating glutamates or aspartates buried in the cytoplasmic membrane and thereby inhibiting ion transport. To demonstrate the function of the Ech complex in ion transport, we further established a procedure to incorporate the enzyme complex into liposomes in an active state. We show the enzyme did not require Na+ for activity and did not translocate 22Na+ into the proteoliposomal lumen. In contrast, Ech activity led to the generation of a pH gradient and membrane potential across the proteoliposomal membrane, demonstrating that the Ech complex of T. kivui is a H+-translocating, H+-reducing enzyme.
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Affiliation(s)
- Alexander Katsyv
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Frankfurt am Main, Germany
| | - Volker Müller
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.
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19
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Haase A, Sawers RG. Exchange of a Single Amino Acid Residue in the HybG Chaperone Allows Maturation of All H 2-Activating [NiFe]-Hydrogenases in Escherichia coli. Front Microbiol 2022; 13:872581. [PMID: 35422773 PMCID: PMC9002611 DOI: 10.3389/fmicb.2022.872581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 03/01/2022] [Indexed: 11/18/2022] Open
Abstract
The biosynthesis of the NiFe(CN)2CO organometallic cofactor of [NiFe]-hydrogenase (Hyd) involves several discreet steps, including the synthesis of the Fe(CN)2CO group on a HypD-HypC scaffold complex. HypC has an additional function in transferring the Fe(CN)2CO group to the apo-precursor of the Hyd catalytic subunit. Bacteria that synthesize more than one Hyd enzyme often have additional HypC-type chaperones specific for each precursor. The specificity determinants of this large chaperone family are not understood. Escherichia coli synthesizes two HypC paralogs, HypC and HybG. HypC delivers the Fe(CN)2CO group to pre-HycE, the precursor of the H2-evolving Hyd-3 enzyme, while HybG transfers the group to the pre-HybC of the H2-oxidizing Hyd-2 enzyme. We could show that a conserved histidine residue around the amino acid position 50 in both HypC and HybG, when exchanged for an alanine, resulted in a severe reduction in the activity of its cognate Hyd enzyme. This reduction in enzyme activity proved to be due to the impaired ability of the chaperones to interact with HypD. Surprisingly, and only in the case of the HybGH52A variant, its co-synthesis with HypD improved its interaction with pre-HycE, resulting in the maturation of Hyd-3. This study demonstrates that the conserved histidine residue helps enhance the interaction of the chaperone with HypD, but additionally, and in E. coli only for HybG, acts as a determinant to prevent the inadvertent maturation of the wrong large-subunit precursor. This study identifies a new level of control exerted by a bacterium synthesizing multiple [NiFe]-Hyd to ensure the correct enzyme is matured only under the appropriate physiological conditions.
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Affiliation(s)
- Alexander Haase
- Institute of Microbiology, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - R Gary Sawers
- Institute of Microbiology, Martin-Luther-University Halle-Wittenberg, Halle, Germany
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20
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Kammel M, Trebbin O, Sawers RG. Interplay between the Conserved Pore Residues Thr-91 and His-209 Controls Formate Translocation through the FocA Channel. Microb Physiol 2022; 32:95-107. [PMID: 35390794 DOI: 10.1159/000524454] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 04/03/2022] [Indexed: 11/19/2022]
Abstract
The formate channel A (FocA) belongs to the formate-nitrite transporter (FNT) family, members of which permeate small monovalent anions. FocA from Escherichia coli translocates formate/formic acid bi-directionally across the cytoplasmic membrane during fermentative growth. Two residues are particularly well conserved within the translocation pores of FNTs: threonine-91 and histidine-209, based on E. coli FocA numbering. These residues are located at the tips of two broken transmembrane helices and control anion passage. H209 is the only charged residue within the pore and interacts with T91. Here, we addressed the role of the T91-H209 interaction network in the permeation of formate in vivo through FocA by performing an extensive amino acid-exchange study. Monitoring changes in intracellular formate using a formate-responsive fdhFP::lacZ reporter system revealed that T91 is essential for the ability of FocA to translocate formate bi-directionally. Only exchange for serine was partially tolerated, indicating that the hydroxyl group of T91 is mechanistically important. Substitution of H209 with N or Q was previously shown to convert FocA into a formate efflux channel. We show here that residue-exchanges A, I and T at this position resulted in a similar phenotype. Moreover, efflux function was confirmed for these FocA variants by measuring excreted formate in the culture medium. Substitution of bulky or charged residues for H209 prevented bi-directional formate passage. Studies using hypophosphite, a toxic analogue of formate taken up by FocA, and which causes impaired growth, confirmed that T91 and H209 substitutions essentially abolished, or drastically reduced, FocA´s translocation activity, as shown by reduction of growth rate. The exceptions were T91S- and T91Y-exchange variants that retained partial ability to take up inhibitory hypophosphite. Together, our findings indicate that T91 is essential for formate permeation in both directions; however, it is particularly important to allow anion efflux. Moreover, H209 is essential for formate uptake by FocA, strongly suggesting that protonation-deprotonation of this residue plays a role in formate uptake. Finally, our results substantiate the premise that efflux and influx of formate by FocA are mechanistically distinct processes that are controlled by the interplay between T91 and H209.
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Affiliation(s)
- Michelle Kammel
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | | | - Robert Gary Sawers
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
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21
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Kammel M, Sawers RG. The FocA channel functions to maintain intracellular formate homeostasis during Escherichia coli fermentation. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35377837 DOI: 10.1099/mic.0.001168] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
FocA translocates formate/formic acid bi-directionally across the cytoplasmic membrane when Escherichia coli grows by fermentation. It remains unclear, however, what physiological benefit is imparted by FocA, because formic acid (pK a=3.75) can diffuse passively across the membrane, especially at low pH. Here, we monitored changes in intra- and extracellular formate levels during batch-culture fermentation, comparing a parental E. coli K-12 strain with its isogenic focA mutant. Our results show that, regardless of the initial pH in the culture, FocA functions to maintain relatively constant intracellular formate levels during growth. Analysis of a strain synthesizing a FocAT91A variant with an exchange in a conserved threonine residue within the translocation pore revealed the strain accumulated formate intracellularly and imported formate poorly, but in a pH-dependent manner, which was different to uptake by native FocA. We conclude that FocA maintains formate homeostasis, using different mechanisms for efflux and uptake of the anion.
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Affiliation(s)
- Michelle Kammel
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3 06120 Halle (Saale), Germany
| | - R Gary Sawers
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3 06120 Halle (Saale), Germany
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22
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Metcalfe GD, Sargent F, Hippler M. Hydrogen production in the presence of oxygen by Escherichia coli K-12. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35343886 PMCID: PMC9558352 DOI: 10.1099/mic.0.001167] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Escherichia coli is a facultative anaerobe that can grow in a variety of environmental conditions. In the complete absence of O2, E. coli can perform a mixed-acid fermentation that contains within it an elaborate metabolism of formic acid. In this study, we use cavity-enhanced Raman spectroscopy (CERS), FTIR, liquid Raman spectroscopy, isotopic labelling and molecular genetics to make advances in the understanding of bacterial formate and H2 metabolism. It is shown that, under anaerobic (anoxic) conditions, formic acid is generated endogenously, excreted briefly from the cell, and then taken up again to be disproportionated to H2 and CO2 by formate hydrogenlyase (FHL-1). However, exogenously added D-labelled formate behaves quite differently from the endogenous formate and is taken up immediately, independently, and possibly by a different mechanism, by the cell and converted to H2 and CO2. Our data support an anion-proton symport model for formic acid transport. In addition, when E. coli was grown in a micro-aerobic (micro-oxic) environment it was possible to analyse aspects of formate and O2 respiration occurring alongside anaerobic metabolism. While cells growing under micro-aerobic conditions generated endogenous formic acid, no H2 was produced. However, addition of exogenous formate at the outset of cell growth did induce FHL-1 biosynthesis and resulted in formate-dependent H2 production in the presence of O2.
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Affiliation(s)
- George D Metcalfe
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK
| | - Frank Sargent
- School of Natural & Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Michael Hippler
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK
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23
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Kammel M, Trebbin O, Pinske C, Sawers RG. A single amino acid exchange converts FocA into a unidirectional efflux channel for formate. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35084298 PMCID: PMC8914244 DOI: 10.1099/mic.0.001132] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
During mixed-acid fermentation, Escherichia coli initially translocates formate out of the cell, but re-imports it at lower pH. This is performed by FocA, the archetype of the formate-nitrite transporter (FNT) family of pentameric anion channels. Each protomer of FocA has a hydrophobic pore through which formate/formic acid is bidirectionally translocated. It is not understood how the direction of formate/formic acid passage through FocA is controlled by pH. A conserved histidine residue (H209) is located within the translocation pore, suggesting that protonation/deprotonation might be linked to the direction of formate translocation. Using a formate-responsive lacZ-based reporter system we monitored changes in formate levels in vivo when H209 in FocA was exchanged for either of the non-protonatable amino acids asparagine or glutamine, which occur naturally in some FNTs. These FocA variants (with N or Q) functioned as highly efficient formate efflux channels and the bacteria could neither accumulate formate nor produce hydrogen gas. Therefore, the data in this study suggest that this central histidine residue within the FocA pore is required for pH-dependent formate uptake into E. coli cells. We also address why H209 is evolutionarily conserved and provide a physiological rationale for the natural occurrence of N/Q variants of FNT channels.
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Affiliation(s)
- Michelle Kammel
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle (Saale), Germany
| | - Oliver Trebbin
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle (Saale), Germany
- Present address: IMD Laboratory Oderland GmbH, Am Kleistpark 1, Frankfurt (Oder), Germany
| | - Constanze Pinske
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle (Saale), Germany
| | - R. Gary Sawers
- Institute for Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle (Saale), Germany
- *Correspondence: R. Gary Sawers,
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24
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Arlt C, Nutschan K, Haase A, Ihling C, Tänzler D, Sinz A, Sawers RG. Native mass spectrometry identifies the HybG chaperone as carrier of the Fe(CN) 2CO group during maturation of E. coli [NiFe]-hydrogenase 2. Sci Rep 2021; 11:24362. [PMID: 34934150 PMCID: PMC8692609 DOI: 10.1038/s41598-021-03900-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/06/2021] [Indexed: 01/27/2023] Open
Abstract
[NiFe]-hydrogenases activate dihydrogen. Like all [NiFe]-hydrogenases, hydrogenase 2 of Escherichia coli has a bimetallic NiFe(CN)2CO cofactor in its catalytic subunit. Biosynthesis of the Fe(CN)2CO group of the [NiFe]-cofactor occurs on a distinct scaffold complex comprising the HybG and HypD accessory proteins. HybG is a member of the HypC-family of chaperones that confers specificity towards immature hydrogenase catalytic subunits during transfer of the Fe(CN)2CO group. Using native mass spectrometry of an anaerobically isolated HybG-HypD complex we show that HybG carries the Fe(CN)2CO group. Our results also reveal that only HybG, but not HypD, interacts with the apo-form of the catalytic subunit. Finally, HybG was shown to have two distinct, and apparently CO2-related, covalent modifications that depended on the presence of the N-terminal cysteine residue on the protein, possibly representing intermediates during Fe(CN)2CO group biosynthesis. Together, these findings suggest that the HybG chaperone is involved in both biosynthesis and delivery of the Fe(CN)2CO group to its target protein. HybG is thus suggested to shuttle between the assembly complex and the apo-catalytic subunit. This study provides new insights into our understanding of how organometallic cofactor components are assembled on a scaffold complex and transferred to their client proteins.
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Affiliation(s)
- Christian Arlt
- Institute of Pharmacy, Center for Structural Mass Spectrometry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle (Saale), Germany
| | - Kerstin Nutschan
- Institute for Biology/Microbiology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120, Halle (Saale), Germany
| | - Alexander Haase
- Institute for Biology/Microbiology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120, Halle (Saale), Germany
| | - Christian Ihling
- Institute of Pharmacy, Center for Structural Mass Spectrometry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle (Saale), Germany
| | - Dirk Tänzler
- Institute of Pharmacy, Center for Structural Mass Spectrometry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle (Saale), Germany
| | - Andrea Sinz
- Institute of Pharmacy, Center for Structural Mass Spectrometry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle (Saale), Germany.
| | - R Gary Sawers
- Institute for Biology/Microbiology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120, Halle (Saale), Germany.
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25
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Modularity of membrane-bound charge-translocating protein complexes. Biochem Soc Trans 2021; 49:2669-2685. [PMID: 34854900 DOI: 10.1042/bst20210462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 11/02/2021] [Accepted: 11/15/2021] [Indexed: 02/05/2023]
Abstract
Energy transduction is the conversion of one form of energy into another; this makes life possible as we know it. Organisms have developed different systems for acquiring energy and storing it in useable forms: the so-called energy currencies. A universal energy currency is the transmembrane difference of electrochemical potential (Δμ~). This results from the translocation of charges across a membrane, powered by exergonic reactions. Different reactions may be coupled to charge-translocation and, in the majority of cases, these reactions are catalyzed by modular enzymes that always include a transmembrane subunit. The modular arrangement of these enzymes allows for different catalytic and charge-translocating modules to be combined. Thus, a transmembrane charge-translocating module can be associated with different catalytic subunits to form an energy-transducing complex. Likewise, the same catalytic subunit may be combined with a different membrane charge-translocating module. In this work, we analyze the modular arrangement of energy-transducing membrane complexes and discuss their different combinations, focusing on the charge-translocating module.
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26
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Birrell JA, Rodríguez-Maciá P, Reijerse EJ, Martini MA, Lubitz W. The catalytic cycle of [FeFe] hydrogenase: A tale of two sites. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214191] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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27
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Insights into the antibacterial mechanism of action of chelating agents by selective deprivation of iron, manganese and zinc. Appl Environ Microbiol 2021; 88:e0164121. [PMID: 34788072 PMCID: PMC8788741 DOI: 10.1128/aem.01641-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial growth and proliferation can be restricted by limiting the availability of metal ions in their environment. Humans sequester iron, manganese, and zinc to help prevent infection by pathogens, a system termed nutritional immunity. Commercially used chelants have high binding affinities with a variety of metal ions, which may lead to antibacterial properties that mimic these innate immune processes. However, the modes of action of many of these chelating agents in bacterial growth inhibition and their selectivity in metal deprivation in cellulo remain ill-defined. We address this shortcoming by examining the effect of 11 chelators on Escherichia coli growth and their impact on the cellular concentration of five metals. The following four distinct effects were uncovered: (i) no apparent alteration in metal composition, (ii) depletion of manganese alongside reductions in iron and zinc levels, (iii) reduced zinc levels with a modest reduction in manganese, and (iv) reduced iron levels coupled with elevated manganese. These effects do not correlate with the absolute known chelant metal ion affinities in solution; however, for at least five chelators for which key data are available, they can be explained by differences in the relative affinity of chelants for each metal ion. The results reveal significant insights into the mechanism of growth inhibition by chelants, highlighting their potential as antibacterials and as tools to probe how bacteria tolerate selective metal deprivation. IMPORTANCE Chelating agents are widely used in industry and consumer goods to control metal availability, with bacterial growth restriction as a secondary benefit for preservation. However, the antibacterial mechanism of action of chelants is largely unknown, particularly with respect to the impact on cellular metal concentrations. The work presented here uncovers distinct metal starvation effects imposed by different chelants on the model Gram-negative bacterium Escherichia coli. The chelators were studied both individually and in pairs, with the majority producing synergistic effects in combinations that maximize antibacterial hostility. The judicious selection of chelants based on contrasting cellular effects should enable reductions in the quantities of chelant required in numerous commercial products and presents opportunities to replace problematic chemistries with biodegradable alternatives.
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28
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Brawley HN, Lindahl PA. Direct Detection of the Labile Nickel Pool in Escherichia coli: New Perspectives on Labile Metal Pools. J Am Chem Soc 2021; 143:18571-18580. [PMID: 34723500 DOI: 10.1021/jacs.1c08213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nickel serves critical roles in the metabolism of E. coli and many prokaryotes. Many details of nickel trafficking are unestablished, but a nonproteinaceous low-molecular-mass (LMM) labile nickel pool (LNiP) is thought to be involved. The portion of the cell lysate that flowed through a 3 kDa cutoff membrane, which ought to contain this pool, was analyzed by size-exclusion and hydrophilic interaction chromatographies (SEC and HILIC) with detection by inductively coupled plasma (ICP) and electrospray ionization (ESI) mass spectrometries. Flow-through-solutions (FTSs) contained 11-15 μM Ni, which represented most Ni in the cell. Chromatograms exhibited 4 major Ni-detected peaks. MS analysis of FTS and prepared nickel complex standards established that these peaks arose from Ni(II) coordinated to oxidized glutathione, histidine, aspartate, and ATP. Surprisingly, Ni complexes with reduced glutathione or citrate were not members of the LNiP under the conditions examined. Aqueous Ni(II) ions were absent in the FTS. Detected complexes were stable in chelator-free buffer but were disrupted by treatment with 1,10-phenanthroline or citrate. Titrating FTS with additional NiSO4 suggested that the total nickel-binding capacity of cytosol is approximately 20-45 μM. Members of the LNiP are probably in rapid equilibrium. Previously reported binding constants to various metalloregulators may have overestimated the relevant binding strength in the cell because aqueous metal salts were used in those determinations. The LNiP may serve as both a Ni reservoir and buffer, allowing cells to accommodate a range of Ni concentrations. The composition of the LNiP may change with cellular metabolism and nutrient status.
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Affiliation(s)
- Hayley N Brawley
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Paul A Lindahl
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.,Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, United States
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29
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Harnessing Escherichia coli for Bio-Based Production of Formate under Pressurized H 2 and CO 2 Gases. Appl Environ Microbiol 2021; 87:e0029921. [PMID: 34647819 DOI: 10.1128/aem.00299-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Escherichia coli is a Gram-negative bacterium that is a workhorse for biotechnology. The organism naturally performs a mixed-acid fermentation under anaerobic conditions where it synthesizes formate hydrogenlyase (FHL-1). The physiological role of the enzyme is the disproportionation of formate into H2 and CO2. However, the enzyme has been observed to catalyze hydrogenation of CO2 given the correct conditions, and so it has possibilities in bio-based carbon capture and storage if it can be harnessed as a hydrogen-dependent CO2 reductase (HDCR). In this study, an E. coli host strain was engineered for the continuous production of formic acid from H2 and CO2 during bacterial growth in a pressurized batch bioreactor. Incorporation of tungsten, in place of molybdenum, in FHL-1 helped to impose a degree of catalytic bias on the enzyme. This work demonstrates that it is possible to couple cell growth to simultaneous, unidirectional formate production from carbon dioxide and develops a process for growth under pressurized gases. IMPORTANCE Greenhouse gas emissions, including waste carbon dioxide, are contributing to global climate change. A basket of solutions is needed to steadily reduce emissions, and one approach is bio-based carbon capture and storage. Here, we present our latest work on harnessing a novel biological solution for carbon capture. The Escherichia coli formate hydrogenlyase (FHL-1) was engineered to be constitutively expressed. Anaerobic growth under pressurized H2 and CO2 gases was established, and aqueous formic acid was produced as a result. Incorporation of tungsten into the enzyme in place of molybdenum proved useful in poising FHL-1 as a hydrogen-dependent CO2 reductase (HDCR).
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30
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Leo F, Schwarz FM, Schuchmann K, Müller V. Capture of carbon dioxide and hydrogen by engineered Escherichia coli: hydrogen-dependent CO 2 reduction to formate. Appl Microbiol Biotechnol 2021; 105:5861-5872. [PMID: 34331557 PMCID: PMC8390402 DOI: 10.1007/s00253-021-11463-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/09/2021] [Accepted: 07/19/2021] [Indexed: 11/24/2022]
Abstract
In times of global climate change and the fear of dwindling resources, we are facing different considerable challenges such as the replacement of fossil fuel-based energy carriers with the coincident maintenance of the increasing energy supply of our growing world population. Therefore, CO2 capturing and H2 storing solutions are urgently needed. In this study, we demonstrate the production of a functional and biotechnological interesting enzyme complex from acetogenic bacteria, the hydrogen-dependent CO2 reductase (HDCR), in the well-known model organism Escherichia coli. We identified the metabolic bottlenecks of the host organisms for the production of the HDCR enzyme complex. Here we show that the recombinant expression of a heterologous enzyme complex transforms E. coli into a whole-cell biocatalyst for hydrogen-driven CO2 reduction to formate without the need of any external co-factors or endogenous enzymes in the reaction process. This shifts the industrial platform organism E. coli more and more into the focus as biocatalyst for CO2-capturing and H2-storage. KEY POINTS: • A functional HDCR enzyme complex was heterologously produced in E. coli. • The metabolic bottlenecks for HDCR production were identified. • HDCR enabled E. coli cell to capture and store H2 and CO2 in the form of formate.
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Affiliation(s)
- Felix Leo
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue-Str. 9, 60439, Frankfurt am Main, Germany
| | - Fabian M Schwarz
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue-Str. 9, 60439, Frankfurt am Main, Germany
| | - Kai Schuchmann
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue-Str. 9, 60439, Frankfurt am Main, Germany
| | - Volker Müller
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue-Str. 9, 60439, Frankfurt am Main, Germany.
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31
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Calisto F, Pereira MM. The Ion-Translocating NrfD-Like Subunit of Energy-Transducing Membrane Complexes. Front Chem 2021; 9:663706. [PMID: 33928068 PMCID: PMC8076601 DOI: 10.3389/fchem.2021.663706] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/19/2021] [Indexed: 11/23/2022] Open
Abstract
Several energy-transducing microbial enzymes have their peripheral subunits connected to the membrane through an integral membrane protein, that interacts with quinones but does not have redox cofactors, the so-called NrfD-like subunit. The periplasmic nitrite reductase (NrfABCD) was the first complex recognized to have a membrane subunit with these characteristics and consequently provided the family's name: NrfD. Sequence analyses indicate that NrfD homologs are present in many diverse enzymes, such as polysulfide reductase (PsrABC), respiratory alternative complex III (ACIII), dimethyl sulfoxide (DMSO) reductase (DmsABC), tetrathionate reductase (TtrABC), sulfur reductase complex (SreABC), sulfite dehydrogenase (SoeABC), quinone reductase complex (QrcABCD), nine-heme cytochrome complex (NhcABCD), group-2 [NiFe] hydrogenase (Hyd-2), dissimilatory sulfite-reductase complex (DsrMKJOP), arsenate reductase (ArrC) and multiheme cytochrome c sulfite reductase (MccACD). The molecular structure of ACIII subunit C (ActC) and Psr subunit C (PsrC), NrfD-like subunits, revealed the existence of ion-conducting pathways. We performed thorough primary structural analyses and built structural models of the NrfD-like subunits. We observed that all these subunits are constituted by two structural repeats composed of four-helix bundles, possibly harboring ion-conducting pathways and containing a quinone/quinol binding site. NrfD-like subunits may be the ion-pumping module of several enzymes. Our data impact on the discussion of functional implications of the NrfD-like subunit-containing complexes, namely in their ability to transduce energy.
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Affiliation(s)
- Filipa Calisto
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universdade de Lisboa, Lisboa, Portugal
| | - Manuela M Pereira
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universdade de Lisboa, Lisboa, Portugal
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32
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Zuchan K, Baymann F, Baffert C, Brugna M, Nitschke W. The dyad of the Y-junction- and a flavin module unites diverse redox enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148401. [PMID: 33684340 DOI: 10.1016/j.bbabio.2021.148401] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/09/2021] [Accepted: 02/16/2021] [Indexed: 11/26/2022]
Abstract
The concomitant presence of two distinctive polypeptide modules, which we have chosen to denominate as the "Y-junction" and the "flavin" module, is observed in 3D structures of enzymes as functionally diverse as complex I, NAD(P)-dependent [NiFe]-hydrogenases and NAD(P)-dependent formate dehydrogenases. Amino acid sequence conservation furthermore suggests that both modules are also part of NAD(P)-dependent [FeFe]-hydrogenases for which no 3D structure model is available yet. The flavin module harbours the site of interaction with the substrate NAD(P) which exchanges two electrons with a strictly conserved flavin moiety. The Y-junction module typically contains four iron-sulphur centres arranged to form a Y-shaped electron transfer conduit and mediates electron transfer between the flavin module and the catalytic units of the respective enzymes. The Y-junction module represents an electron transfer hub with three potential electron entry/exit sites. The pattern of specific redox centres present both in the Y-junction and the flavin module is correlated to present knowledge of these enzymes' functional properties. We have searched publicly accessible genomes for gene clusters containing both the Y-junction and the flavin module to assemble a comprehensive picture of the diversity of enzymes harbouring this dyad of modules and to reconstruct their phylogenetic relationships. These analyses indicate the presence of the dyad already in the last universal common ancestor and the emergence of complex I's EFG-module out of a subgroup of NAD(P)- dependent formate dehydrogenases.
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Affiliation(s)
- Kilian Zuchan
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
| | - Frauke Baymann
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
| | - Carole Baffert
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
| | - Myriam Brugna
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France.
| | - Wolfgang Nitschke
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
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33
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Calisto F, Sousa FM, Sena FV, Refojo PN, Pereira MM. Mechanisms of Energy Transduction by Charge Translocating Membrane Proteins. Chem Rev 2021; 121:1804-1844. [PMID: 33398986 DOI: 10.1021/acs.chemrev.0c00830] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Life relies on the constant exchange of different forms of energy, i.e., on energy transduction. Therefore, organisms have evolved in a way to be able to harvest the energy made available by external sources (such as light or chemical compounds) and convert these into biological useable energy forms, such as the transmembrane difference of electrochemical potential (Δμ̃). Membrane proteins contribute to the establishment of Δμ̃ by coupling exergonic catalytic reactions to the translocation of charges (electrons/ions) across the membrane. Irrespectively of the energy source and consequent type of reaction, all charge-translocating proteins follow two molecular coupling mechanisms: direct- or indirect-coupling, depending on whether the translocated charge is involved in the driving reaction. In this review, we explore these two coupling mechanisms by thoroughly examining the different types of charge-translocating membrane proteins. For each protein, we analyze the respective reaction thermodynamics, electron transfer/catalytic processes, charge-translocating pathways, and ion/substrate stoichiometries.
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Affiliation(s)
- Filipa Calisto
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
| | - Filipe M Sousa
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
| | - Filipa V Sena
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
| | - Patricia N Refojo
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal
| | - Manuela M Pereira
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
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34
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Poladyan A, Blbulyan S, Semashko T, Dziameshka V, Zhukouskaya L, Trchоunian A. Application of organic waste glycerol to produce crude extracts of bacterial cells and microbial hydrogenase-the anode enzymes of bio-electrochemical systems. FEMS Microbiol Lett 2021; 367:5817844. [PMID: 32267913 DOI: 10.1093/femsle/fnaa056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 03/26/2020] [Indexed: 01/08/2023] Open
Abstract
Glycerol is an organic waste material that can be used for the production of microbial biomass, consequently providing valuable biocatalysts promoting the generation of electrical current in microbial fuel cells (MFCs). [NiFe]-Hydrogenases (Hyds) of Escherichia coli and Ralstonia eutropha may be applied as potential anode biocatalysts in MFCs. In this study, E. coli K12 whole cells or crude extracts and R. eutropha HF649 synthesizing Strep-tagged membrane-bound Hyds (MBH) were evaluated as anode enzymes in a bioelectrochemical system. The samples were immobilized on the sensors with polyvinyl acetate support. Mediators like ferrocene and its derivatives (ferrocene-carboxy-aldehyde, ferrocene-carboxylic acid, methyl-ferrocene-methanol) were employed. The maximal level of bioelectrocatalytic activity of Hyds was demonstrated at 500 mV voltage. Depending on the mediator and biocatalyst, current strength varied from 5 to 42 μA. Introduction of ferrocene-carboxylic acid enhanced current strength; moreover, the current flow was directly correlated with H2 concentration. The maximal value (up to 150 μA) of current strength was achieved with a 2-fold hydrogen supply. It may be inferred that Hyds are efficiently produced by E. coli and R. eutropha grown on glycerol, while ferrocene derivatives act as agents mediating the electrochemical activity of Hyds.
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Affiliation(s)
- Anna Poladyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia
| | - Syuzanna Blbulyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia
| | - Tatiana Semashko
- Institute of Microbiology, NAS Belarus, 2 Kuprevich Str., 220141 Minsk, Belarus
| | - Volha Dziameshka
- Institute of Microbiology, NAS Belarus, 2 Kuprevich Str., 220141 Minsk, Belarus
| | | | - Armen Trchоunian
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia.,Research Institute of Biology, Biology Faculty, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia
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35
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Engineering an efficient H2 utilizing Escherichia coli platform by modulation of endogenous hydrogenases. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2020.107851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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36
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Lin WY, Liaw SJ. Deacidification by FhlA-dependent hydrogenase is involved in urease activity and urinary stone formation in uropathogenic Proteus mirabilis. Sci Rep 2020; 10:19546. [PMID: 33177598 PMCID: PMC7658346 DOI: 10.1038/s41598-020-76561-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/26/2020] [Indexed: 11/09/2022] Open
Abstract
Proteus mirabilis is an important uropathogen, featured with urinary stone formation. Formate hydrogenlyase (FHL), consisting of formate dehydrogenase H and hydrogenase for converting proton to hydrogen, has been implicated in virulence. In this study, we investigated the role of P. mirabilis FHL hydrogenase and the FHL activator, FhlA. fhlA and hyfG (encoding hydrogenase large subunit) displayed a defect in acid resistance. fhlA and hyfG mutants displayed a delay in medium deacidification compared to wild-type and ureC mutant failed to deacidify the medium. In addition, loss of fhlA or hyfG decreased urease activity in the pH range of 5-8. The reduction of urease activities in fhlA and hyfG mutants subsided gradually over the pH range and disappeared at pH 9. Furthermore, mutation of fhlA or hyfG resulted in a decrease in urinary stone formation in synthetic urine. These indicate fhlA- and hyf-mediated deacidification affected urease activity and stone formation. Finally, fhlA and hyfG mutants exhibited attenuated colonization in mice. Altogether, we found expression of fhlA and hyf confers medium deacidification via facilitating urease activity, thereby urinary stone formation and mouse colonization. The link of acid resistance to urease activity provides a potential strategy for counteracting urinary tract infections by P. mirabilis.
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Affiliation(s)
- Wen-Yuan Lin
- Department and Graduate Institute of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, No. 1, Chang-Te Street, Taipei, 10016, Taiwan, ROC
| | - Shwu-Jen Liaw
- Department and Graduate Institute of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, No. 1, Chang-Te Street, Taipei, 10016, Taiwan, ROC. .,Department of Laboratory Medicine, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan, Republic of China.
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37
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Finney AJ, Buchanan G, Palmer T, Coulthurst SJ, Sargent F. Activation of a [NiFe]-hydrogenase-4 isoenzyme by maturation proteases. MICROBIOLOGY (READING, ENGLAND) 2020; 166:854-860. [PMID: 32731905 PMCID: PMC7654741 DOI: 10.1099/mic.0.000963] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 07/22/2020] [Indexed: 12/23/2022]
Abstract
Maturation of [NiFe]-hydrogenases often involves specific proteases responsible for cleavage of the catalytic subunits. Escherichia coli HycI is the protease dedicated to maturation of the Hydrogenase-3 isoenzyme, a component of formate hydrogenlyase-1. In this work, it is demonstrated that a Pectobacterium atrosepticum HycI homologue, HyfK, is required for hydrogenase-4 activity, a component of formate hydrogenlyase-2, in that bacterium. The P. atrosepticum ΔhyfK mutant phenotype could be rescued by either P. atrosepticum hyfK or E. coli hycI on a plasmid. Conversely, an E. coli ΔhycI mutant was complemented by either E. coli hycI or P. atrosepticum hyfK in trans. E. coli is a rare example of a bacterium containing both hydrogenase-3 and hydrogenase-4, however the operon encoding hydrogenase-4 has no maturation protease gene. This work suggests HycI should be sufficient for maturation of both E. coli formate hydrogenlyases, however no formate hydrogenlyase-2 activity was detected in any E. coli strains tested here.
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Affiliation(s)
- Alexander J. Finney
- School of Natural & Environmental Sciences, Faculty of Science, Agriculture & Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
| | - Grant Buchanan
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
- Institute of Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Tracy Palmer
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
- Institute of Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | | | - Frank Sargent
- School of Natural & Environmental Sciences, Faculty of Science, Agriculture & Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
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38
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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: 7] [Impact Index Per Article: 1.8] [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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Petrosyan H, Vanyan L, Mirzoyan S, Trchounian A, Trchounian K. Roasted coffee wastes as a substrate for Escherichia coli to grow and produce hydrogen. FEMS Microbiol Lett 2020; 367:5848194. [DOI: 10.1093/femsle/fnaa088] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 05/27/2020] [Indexed: 12/25/2022] Open
Abstract
ABSTRACT
After brewing roasted coffee, spent coffee grounds (SCGs) are generated being one of the daily wastes emerging in dominant countries with high rate and big quantity. Escherichia coli BW25113 wild-type strain, mutants with defects in hydrogen (H2)-producing/oxidizing four hydrogenases (Hyd) (ΔhyaB ΔhybC, ΔhycE, ΔhyfG) and septuple mutant (ΔhyaB ΔhybC ΔhycA ΔfdoG ΔldhA ΔfrdC ΔaceE) were investigated by measuring change of external pH, bacterial growth and H2 production during the utilization of SCG hydrolysate. In wild type, H2 was produced with rate of 1.28 mL H2 (g sugar)−1 h−1 yielding 30.7 mL H2 (g sugar)−1 or 2.75 L (kg SCG)−1 during 24 h. In septuple mutant, H2 production yield was 72 mL H2 (g sugar)−1 with rate of 3 mL H2 (g sugar)−1 h−1. H2 generation was absent in hycE single mutant showing the main role of Hyd-3 in H2 production. During utilization of SCG wild type, specific growth rate was 0.72 ± 0.01 h−1 with biomass yield of 0.3 g L−1. Genetic modifications and control of external parameters during growth could lead to prolonged and enhanced microbiological H2 production by organic wastes, which will aid more efficiently global sustainable energy needs resulting in diversification of mobile and fixed energy sources.
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Affiliation(s)
- Hripsime Petrosyan
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan, Armenia
- Scientific Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025 Yerevan, Armenia
| | - Liana Vanyan
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan, Armenia
- Scientific Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025 Yerevan, Armenia
| | - Satenik Mirzoyan
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan, Armenia
- Scientific Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025 Yerevan, Armenia
| | - Armen Trchounian
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan, Armenia
- Scientific Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
| | - Karen Trchounian
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan, Armenia
- Scientific Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025 Yerevan, Armenia
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40
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Brauer AL, Learman BS, Armbruster CE. Ynt is the primary nickel import system used by Proteus mirabilis and specifically contributes to fitness by supplying nickel for urease activity. Mol Microbiol 2020; 114:185-199. [PMID: 32255226 DOI: 10.1111/mmi.14505] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 01/03/2023]
Abstract
Proteus mirabilis is a Gram-negative uropathogen and frequent cause of catheter-associated urinary tract infection (CAUTI). One important virulence factor is its urease enzyme, which requires nickel to be catalytically active. It is, therefore, hypothesized that nickel import is critical for P. mirabilis urease activity and pathogenesis during infection. P. mirabilis strain HI4320 encodes two putative nickel import systems, designated Nik and Ynt. By disrupting the substrate-binding proteins from each import system (nikA and yntA), we show that Ynt is the primary nickel importer, while Nik only compensates for loss of Ynt at high nickel concentrations. We further demonstrate that these are the only binding proteins capable of importing nickel for incorporation into the urease enzyme. Loss of either nickel-binding protein results in a significant fitness defect in a murine model of CAUTI, but YntA is more crucial as the yntA mutant was significantly outcompeted by the nikA mutant. Furthermore, despite the importance of nickel transport for hydrogenase activity, the sole contribution of yntA and nikA to virulence is due to their role in urease activity, as neither mutant exhibited a fitness defect when disrupted in a urease-negative background.
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Affiliation(s)
- Aimee L Brauer
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Brian S Learman
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Chelsie E Armbruster
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
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Benoit SL, Maier RJ, Sawers RG, Greening C. Molecular Hydrogen Metabolism: a Widespread Trait of Pathogenic Bacteria and Protists. Microbiol Mol Biol Rev 2020; 84:e00092-19. [PMID: 31996394 PMCID: PMC7167206 DOI: 10.1128/mmbr.00092-19] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pathogenic microorganisms use various mechanisms to conserve energy in host tissues and environmental reservoirs. One widespread but often overlooked means of energy conservation is through the consumption or production of molecular hydrogen (H2). Here, we comprehensively review the distribution, biochemistry, and physiology of H2 metabolism in pathogens. Over 200 pathogens and pathobionts carry genes for hydrogenases, the enzymes responsible for H2 oxidation and/or production. Furthermore, at least 46 of these species have been experimentally shown to consume or produce H2 Several major human pathogens use the large amounts of H2 produced by colonic microbiota as an energy source for aerobic or anaerobic respiration. This process has been shown to be critical for growth and virulence of the gastrointestinal bacteria Salmonella enterica serovar Typhimurium, Campylobacter jejuni, Campylobacter concisus, and Helicobacter pylori (including carcinogenic strains). H2 oxidation is generally a facultative trait controlled by central regulators in response to energy and oxidant availability. Other bacterial and protist pathogens produce H2 as a diffusible end product of fermentation processes. These include facultative anaerobes such as Escherichia coli, S Typhimurium, and Giardia intestinalis, which persist by fermentation when limited for respiratory electron acceptors, as well as obligate anaerobes, such as Clostridium perfringens, Clostridioides difficile, and Trichomonas vaginalis, that produce large amounts of H2 during growth. Overall, there is a rich literature on hydrogenases in growth, survival, and virulence in some pathogens. However, we lack a detailed understanding of H2 metabolism in most pathogens, especially obligately anaerobic bacteria, as well as a holistic understanding of gastrointestinal H2 transactions overall. Based on these findings, we also evaluate H2 metabolism as a possible target for drug development or other therapies.
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Affiliation(s)
- Stéphane L Benoit
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Robert J Maier
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - R Gary Sawers
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia
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Schoelmerich MC, Müller V. Energy-converting hydrogenases: the link between H 2 metabolism and energy conservation. Cell Mol Life Sci 2019; 77:1461-1481. [PMID: 31630229 DOI: 10.1007/s00018-019-03329-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/17/2019] [Accepted: 10/01/2019] [Indexed: 10/25/2022]
Abstract
The reversible interconversion of molecular hydrogen and protons is one of the most ancient microbial metabolic reactions and catalyzed by hydrogenases. A widespread yet largely enigmatic group comprises multisubunit [NiFe] hydrogenases, that directly couple H2 metabolism to the electrochemical ion gradient across the membranes of bacteria and of archaea. These complexes are collectively referred to as energy-converting hydrogenases (Ech), as they reversibly transform redox energy into physicochemical energy. Redox energy is typically provided by a low potential electron donor such as reduced ferredoxin to fuel H2 evolution and the establishment of a transmembrane electrochemical ion gradient ([Formula: see text]). The [Formula: see text] is then utilized by an ATP synthase for energy conservation by generating ATP. This review describes the modular structure/function of Ech complexes, focuses on insights into the energy-converting mechanisms, describes the evolutionary context and delves into the implications of relying on an Ech complex as respiratory enzyme for microbial metabolism.
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Affiliation(s)
- Marie Charlotte Schoelmerich
- Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany.,Microbiology and Biotechnology, Institute of Plant Sciences and Microbiology, Universität Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Volker Müller
- Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany.
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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: 41] [Impact Index Per Article: 8.2] [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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Finney AJ, Lowden R, Fleszar M, Albareda M, Coulthurst SJ, Sargent F. The plant pathogen Pectobacterium atrosepticum contains a functional formate hydrogenlyase-2 complex. Mol Microbiol 2019; 112:1440-1452. [PMID: 31420965 PMCID: PMC7384014 DOI: 10.1111/mmi.14370] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2019] [Indexed: 12/19/2022]
Abstract
Pectobacterium atrosepticum SCRI1043 is a phytopathogenic Gram-negative enterobacterium. Genomic analysis has identified that genes required for both respiration and fermentation are expressed under anaerobic conditions. One set of anaerobically expressed genes is predicted to encode an important but poorly understood membrane-bound enzyme termed formate hydrogenlyase-2 (FHL-2), which has fascinating evolutionary links to the mitochondrial NADH dehydrogenase (Complex I). In this work, molecular genetic and biochemical approaches were taken to establish that FHL-2 is fully functional in P. atrosepticum and is the major source of molecular hydrogen gas generated by this bacterium. The FHL-2 complex was shown to comprise a rare example of an active [NiFe]-hydrogenase-4 (Hyd-4) isoenzyme, itself linked to an unusual selenium-free formate dehydrogenase in the final complex. In addition, further genetic dissection of the genes encoding the predicted membrane arm of FHL-2 established surprisingly that the majority of genes encoding this domain are not required for physiological hydrogen production activity. Overall, this study presents P. atrosepticum as a new model bacterial system for understanding anaerobic formate and hydrogen metabolism in general, and FHL-2 function and structure in particular.
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Affiliation(s)
- Alexander J Finney
- School of Natural & Environmental Sciences, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.,School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Rebecca Lowden
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Michal Fleszar
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Marta Albareda
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.,Centro de Biotecnología y Genómica de Plantas (C.B.G.P.) UPM-INIA, Universidad Politécnica de Madrid, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Spain
| | | | - Frank Sargent
- School of Natural & Environmental Sciences, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.,School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
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del Barrio M, Guendon C, Kpebe A, Baffert C, Fourmond V, Brugna M, Léger C. Valine-to-Cysteine Mutation Further Increases the Oxygen Tolerance of Escherichia coli NiFe Hydrogenase Hyd-1. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00543] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Melisa del Barrio
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
| | - Chloé Guendon
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
| | - Arlette Kpebe
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
| | - Carole Baffert
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
| | - Vincent Fourmond
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
| | - Myriam Brugna
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
| | - Christophe Léger
- CNRS, Bioénergétique et Ingénierie des Protéines, Aix Marseille University, 13009 Marseille, France
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46
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Energy conservation by a hydrogenase-dependent chemiosmotic mechanism in an ancient metabolic pathway. Proc Natl Acad Sci U S A 2019; 116:6329-6334. [PMID: 30850546 DOI: 10.1073/pnas.1818580116] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The ancient reductive acetyl-CoA pathway is employed by acetogenic bacteria to form acetate from inorganic energy sources. Since the central pathway does not gain net ATP by substrate-level phosphorylation, chemolithoautotrophic growth relies on the additional formation of ATP via a chemiosmotic mechanism. Genome analyses indicated that some acetogens only have an energy-converting, ion-translocating hydrogenase (Ech) as a potential respiratory enzyme. Although the Ech-encoding genes are widely distributed in nature, the proposed function of Ech as an ion-translocating chemiosmotic coupling site has neither been demonstrated in bacteria nor has it been demonstrated that it can be the only energetic coupling sites in microorganisms that depend on a chemiosmotic mechanism for energy conservation. Here, we show that the Ech complex of the thermophilic acetogenic bacterium Thermoanaerobacter kivui is indeed a respiratory enzyme. Experiments with resting cells prepared from T. kivui cultures grown on carbon monoxide (CO) revealed CO oxidation coupled to H2 formation and the generation of a transmembrane electrochemical ion gradient ([Formula: see text]). Inverted membrane vesicles (IMVs) prepared from CO-grown cells also produced H2 and ATP from CO (via a loosely attached CO dehydrogenase) or a chemical reductant. Finally, we show that Ech activity led to the translocation of both H+ and Na+ across the membrane of the IMVs. The H+ gradient was then used by the ATP synthase for energy conservation. These data demonstrate that the energy-converting hydrogenase in concert with an ATP synthase may be the simplest form of respiration; it combines carbon dioxide fixation with the synthesis of ATP in an ancient pathway.
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47
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Finney AJ, Sargent F. Formate hydrogenlyase: A group 4 [NiFe]-hydrogenase in tandem with a formate dehydrogenase. Adv Microb Physiol 2019; 74:465-486. [PMID: 31126535 DOI: 10.1016/bs.ampbs.2019.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hydrogenase enzymes are currently under the international research spotlight due to emphasis on biologically produced hydrogen as one potential energy carrier to relinquish the requirement for 'fossil fuel' derived energy. Three major classes of hydrogenase exist in microbes all able to catalyze the reversible oxidation of dihydrogen to protons and electrons. These classes are defined by their active site metal content: [NiFe]-; [FeFe]- and [Fe]-hydrogenases. Of these the [NiFe]-hydrogenases have links to ancient forms of metabolism, utilizing hydrogen as the original source of reductant on Earth. This review progresses to highlight the Group 4 [NiFe]-hydrogenase enzymes that preferentially generate hydrogen exploiting various partner enzymes or ferredoxin, while in some cases translocating ions across biological membranes. Specific focus is paid to Group 4A, the Formate hydrogenlyase complexes. These are the combination of a six or nine subunit [NiFe]-hydrogenase with a soluble formate dehydrogenase to derived electrons from formate oxidation for proton reduction. The incidence, physiology, structure and biotechnological application of these complexes will be explored with attention on Escherichia coli Formate Hydrogenlyase-1 (FHL-1).
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Affiliation(s)
- Alexander J Finney
- Devonshire Centre for Biosystems Science & Engineering, School of Natural & Environmental Sciences, Newcastle University, Newcastle-Upon-Tyne NE1 7RU, England, United Kingdom
| | - Frank Sargent
- Devonshire Centre for Biosystems Science & Engineering, School of Natural & Environmental Sciences, Newcastle University, Newcastle-Upon-Tyne NE1 7RU, England, United Kingdom
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48
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Abstract
Hydrogenases are metal-containing biocatalysts that reversibly convert protons and electrons to hydrogen gas. This reaction can contribute in different ways to the generation of the proton motive force (PMF) of a cell. One means of PMF generation involves reduction of protons on the inside of the cytoplasmic membrane, releasing H2 gas, which being without charge is freely diffusible across the cytoplasmic membrane, where it can be re-oxidized to release protons. A second route of PMF generation couples transfer of electrons derived from H2 oxidation to quinone reduction and concomitant proton uptake at the membrane-bound heme cofactor. This redox-loop mechanism, as originally formulated by Mitchell, requires a second, catalytically distinct, enzyme complex to re-oxidize quinol and release the protons outside the cell. A third way of generating PMF is also by electron transfer to quinones but on the outside of the membrane while directly drawing protons through the entire membrane. The cofactor-less membrane subunits involved are proposed to operate by a conformational mechanism (redox-linked proton pump). Finally, PMF can be generated through an electron bifurcation mechanism, whereby an exergonic reaction is tightly coupled with an endergonic reaction. In all cases the protons can be channelled back inside through a F1F0-ATPase to convert the 'energy' stored in the PMF into the universal cellular energy currency, ATP. New and exciting discoveries employing these mechanisms have recently been made on the bioenergetics of hydrogenases, which will be discussed here and placed in the context of their contribution to energy conservation.
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Affiliation(s)
- Constanze Pinske
- Institute of Biology/Microbiology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle/Saale, Germany
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49
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Albareda M, Pacios LF, Palacios JM. Computational analyses, molecular dynamics, and mutagenesis studies of unprocessed form of [NiFe] hydrogenase reveal the role of disorder for efficient enzyme maturation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:325-340. [PMID: 30703364 DOI: 10.1016/j.bbabio.2019.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 12/10/2018] [Accepted: 01/25/2019] [Indexed: 12/29/2022]
Abstract
Biological production and oxidation of hydrogen is mediated by hydrogenases, key enzymes for these energy-relevant reactions. Synthesis of [NiFe] hydrogenases involves a complex series of biochemical reactions to assemble protein subunits and metallic cofactors required for enzyme function. A final step in this biosynthetic pathway is the processing of a C-terminal tail (CTT) from its large subunit, thus allowing proper insertion of nickel in the unique NiFe(CN)2CO cofactor present in these enzymes. In silico modelling and Molecular Dynamics (MD) analyses of processed vs. unprocessed forms of Rhizobium leguminosarum bv. viciae (Rlv) hydrogenase large subunit HupL showed that its CTT (residues 582-596) is an intrinsically disordered region (IDR) that likely provides the required flexibility to the protein for the final steps of proteolytic maturation. Prediction of pKa values of ionizable side chains in both forms of the enzyme's large subunit also revealed that the presence of the CTT strongly modify the protonation state of some key residues around the active site. Furthermore, MD simulations and mutant analyses revealed that two glutamate residues (E27 in the N-terminal region and E589 inside the CTT) likely contribute to the process of nickel incorporation into the enzyme. Computational analysis also revealed structural details on the interaction of Rlv hydrogenase LSU with the endoprotease HupD responsible for the removal of CTT.
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Affiliation(s)
- Marta Albareda
- Centro de Biotecnología y Genómica de Plantas (C.B.G.P.) UPM-INIA, Universidad Politécnica de Madrid, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Spain; Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain
| | - Luis F Pacios
- Centro de Biotecnología y Genómica de Plantas (C.B.G.P.) UPM-INIA, Universidad Politécnica de Madrid, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Spain; Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain.
| | - Jose M Palacios
- Centro de Biotecnología y Genómica de Plantas (C.B.G.P.) UPM-INIA, Universidad Politécnica de Madrid, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Spain; Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain.
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50
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Zanello P. Structure and electrochemistry of proteins harboring iron-sulfur clusters of different nuclearities. Part IV. Canonical, non-canonical and hybrid iron-sulfur proteins. J Struct Biol 2019; 205:103-120. [PMID: 30677521 DOI: 10.1016/j.jsb.2019.01.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 01/11/2019] [Accepted: 01/11/2019] [Indexed: 12/26/2022]
Abstract
A plethora of proteins are able to express iron-sulfur clusters, but have a clear picture of the different types of proteins and the different iron-sulfur clusters they harbor it is not easy. In the last five years we have reviewed structure/electrochemistry of metalloproteins expressing: (i) single types of iron-sulfur clusters (namely: {Fe(Cys)4}, {[Fe2S2](Cys)4}, {[Fe2S2](Cys)3(X)} (X = Asp, Arg, His), {[Fe2S2](Cys)2(His)2}, {[Fe3S4](Cys)3}, {[Fe4S4](Cys)4} and {[Fe4S4](Cys)3(nonthiolate ligand)} cores); (ii) metalloproteins harboring iron-sulfur centres of different nuclearities (namely: [4Fe-4S] and [2Fe-2S], [4Fe-4S] and [3Fe-4S], and [4Fe-4S], [3Fe-4S] and [2Fe-2S] clusters. Our target is now to review structure and electrochemistry of proteins harboring canonical, non-canonical and hybrid iron-sulfur proteins.
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Affiliation(s)
- Piero Zanello
- Dipartimento di Biotecnologie, Chimica e Farmacia dell'Università di Siena, Via A. De Gasperi 2, 53100 Siena, Italy
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