1
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Gasteazoro F, Catucci G, Barbieri L, De Angelis M, Dalla Costa A, Sadeghi SJ, Gilardi G, Valetti F. Cascade reactions with two non-physiological partners for NAD(P)H regeneration via renewable hydrogen. Biotechnol J 2024; 19:e2300567. [PMID: 38581100 DOI: 10.1002/biot.202300567] [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: 10/20/2023] [Revised: 03/14/2024] [Accepted: 03/15/2024] [Indexed: 04/08/2024]
Abstract
An attractive application of hydrogenases, combined with the availability of cheap and renewable hydrogen (i.e., from solar and wind powered electrolysis or from recycled wastes), is the production of high-value electron-rich intermediates such as reduced nicotinamide adenine dinucleotides. Here, the capability of a very robust and oxygen-resilient [FeFe]-hydrogenase (CbA5H) from Clostridium beijerinckii SM10, previously identified in our group, combined with a reductase (BMR) from Bacillus megaterium (now reclassified as Priestia megaterium) was tested. The system shows a good stability and it was demonstrated to reach up to 28 ± 2 nmol NADPH regenerated s-1 mg of hydrogenase-1 (i.e., 1.68 ± 0.12 U mg-1, TOF: 126 ± 9 min-1) and 0.46 ± 0.04 nmol NADH regenerated s-1 mg of hydrogenase-1 (i.e., 0.028 ± 0.002 U mg-1, TOF: 2.1 ± 0.2 min-1), meaning up to 74 mg of NADPH and 1.23 mg of NADH produced per hour by a system involving 1 mg of CbA5H. The TOF is comparable with similar systems based on hydrogen as regenerating molecule for NADPH, but the system is first of its kind as for the [FeFe]-hydrogenase and the non-physiological partners used. As a proof of concept a cascade reaction involving CbA5H, BMR and a mutant BVMO from Acinetobacter radioresistens able to oxidize indole is presented. The data show how the cascade can be exploited for indigo production and multiple reaction cycles can be sustained using the regenerated NADPH.
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Affiliation(s)
- Francisco Gasteazoro
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
- CICATA Unidad Morelos, Instituto Politécnico Nacional, Mexico D. F., Mexico
| | - Gianluca Catucci
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | - Lisa Barbieri
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
- University School for Advanced Studies IUSS Pavia, Pavia, Italy
| | - Melissa De Angelis
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | | | - Sheila J Sadeghi
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | - Gianfranco Gilardi
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | - Francesca Valetti
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
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Liu C, Schmitz RA, Pol A, Hogendoorn C, Verhagen D, Peeters SH, van Alen TA, Cremers G, Mesman RA, Op den Camp HJM. Active coexistence of the novel gammaproteobacterial methanotroph 'Ca. Methylocalor cossyra' CH1 and verrucomicrobial methanotrophs in acidic, hot geothermal soil. Environ Microbiol 2024; 26:e16602. [PMID: 38454738 DOI: 10.1111/1462-2920.16602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 02/16/2024] [Indexed: 03/09/2024]
Abstract
Terrestrial geothermal ecosystems are hostile habitats, characterized by large emissions of environmentally relevant gases such as CO2 , CH4 , H2 S and H2 . These conditions provide a niche for chemolithoautotrophic microorganisms. Methanotrophs of the phylum Verrucomicrobia, which inhabit these ecosystems, can utilize these gases and grow at pH levels below 1 and temperatures up to 65°C. In contrast, methanotrophs of the phylum Proteobacteria are primarily found in various moderate environments. Previously, novel verrucomicrobial methanotrophs were detected and isolated from the geothermal soil of the Favara Grande on the island of Pantelleria, Italy. The detection of pmoA genes, specific for verrucomicrobial and proteobacterial methanotrophs in this environment, and the partially overlapping pH and temperature growth ranges of these isolates suggest that these distinct phylogenetic groups could coexist in the environment. In this report, we present the isolation and characterization of a thermophilic and acid-tolerant gammaproteobacterial methanotroph (family Methylococcaceae) from the Favara Grande. This isolate grows at pH values ranging from 3.5 to 7.0 and temperatures from 35°C to 55°C, and diazotrophic growth was demonstrated. Its genome contains genes encoding particulate and soluble methane monooxygenases, XoxF- and MxaFI-type methanol dehydrogenases, and all enzymes of the Calvin cycle. For this novel genus and species, we propose the name 'Candidatus Methylocalor cossyra' CH1.
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Affiliation(s)
- Changqing Liu
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Rob A Schmitz
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Arjan Pol
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Carmen Hogendoorn
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Daniël Verhagen
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Stijn H Peeters
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Theo A van Alen
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Geert Cremers
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Rob A Mesman
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Huub J M Op den Camp
- Department of Microbiology, Faculty of Science, Radboud Institute for Biological and Environmental Sciences, Radboud University Nijmegen, Nijmegen, the Netherlands
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3
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Angenent SC, Schuttinga JH, van Efferen MFH, Kuizenga B, van Bree B, van der Krieken RO, Verhoeven TJ, Wijffels RH. Hydrogen Oxidizing Bacteria as Novel Protein Source for Human Consumption: An Overview. Open Microbiol J 2022. [DOI: 10.2174/18742858-v16-e2207270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The increasing threat of climate change combined with the prospected growth in the world population puts an enormous pressure on the future demand for sustainable protein sources for human consumption. In this review, hydrogen oxidizing bacteria (HOB) are presented as a novel protein source that could play a role in fulfilling this future demand. HOB are species of bacteria that merely require an inflow of the gasses hydrogen, oxygen, carbon dioxide, and a nitrogen source to grow in a conventional bioreactor. Cupriavidus necator is proposed as HOB for industrial cultivation due to its remarkably high protein content (up to 70% of mass), suitability for cultivation in a bioreactor, and the vast amount of available background information. A broad overview of the unique aspects of the bacteria will be provided, from the production process, amino acid composition, and source of the required gasses to the future acceptance of HOB into the market.
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4
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Lettau E, Zill D, Späth M, Lorent C, Singh P, Lauterbach L. Catalytic and spectroscopic properties of the halotolerant soluble methane monooxygenase reductase from Methylomonas methanica MC09. Chembiochem 2021; 23:e202100592. [PMID: 34905639 PMCID: PMC9305295 DOI: 10.1002/cbic.202100592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/13/2021] [Indexed: 11/10/2022]
Abstract
The soluble methane monooxygenase receives electrons from NADH via its reductase MmoC for oxidation of methane, which is itself an attractive C1 building block for a future bioeconomy. Herein, we present biochemical and spectroscopic insights into the reductase from the marine methanotroph Methylomonas methanica MC09. The presence of a flavin adenine dinucleotide (FAD) and [2Fe2S] cluster as its prosthetic group were revealed by reconstitution experiments, iron determination and electron paramagnetic resonance spectroscopy. As a true halotolerant enzyme, MmoC still showed 50 % of its specific activity at 2 M NaCl. We show that MmoC produces only trace amounts of superoxide, but mainly hydrogen peroxide during uncoupled turnover reactions. The characterization of a highly active reductase is an important step for future biotechnological applications of a halotolerant sMMO.
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Affiliation(s)
- Elisabeth Lettau
- Rheinisch-Westfälische Technische Hochschule Aachen: Rheinisch-Westfalische Technische Hochschule Aachen, Institute of Applied Microbiology, GERMANY
| | - Domenic Zill
- Rheinisch Westfalische Technische Hochschule Aachen Fakultat fur Mathematik Informatik und Naturwissenschaften, Institute of Applied Microbiology, GERMANY
| | - Marta Späth
- Technische Universität Berlin: Technische Universitat Berlin, Institute of Chemistry, GERMANY
| | - Christian Lorent
- Technische Universität Berlin: Technische Universitat Berlin, Institute of Chemistry, GERMANY
| | - Praveen Singh
- Rheinisch-Westfälische Technische Hochschule Aachen: Rheinisch-Westfalische Technische Hochschule Aachen, Institute of Applied Microbiology, GERMANY
| | - Lars Lauterbach
- Technische Universitat Berlin, Chemistry, Strasse des 17. Juni 135, Max-Volmer-Laboratorium, Sekr. PC 14, 10623, Berlin, Germany, GERMANY
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5
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Fan Q, Neubauer P, Gimpel M. Production of soluble regulatory hydrogenase from Ralstonia eutropha in Escherichia coli using a fed-batch-based autoinduction system. Microb Cell Fact 2021; 20:201. [PMID: 34663324 PMCID: PMC8522226 DOI: 10.1186/s12934-021-01690-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/27/2021] [Indexed: 02/06/2023] Open
Abstract
Background Autoinduction systems can regulate protein production in Escherichia coli without the need to monitor cell growth or add inducer at the proper time following culture growth. Compared to classical IPTG induction, autoinduction provides a simple and fast way to obtain high protein yields. In the present study, we report on the optimization process for the enhanced heterologous production of the Ralstonia eutropha regulatory hydrogenase (RH) in E. coli using autoinduction. These autoinduction methods were combined with the EnPresso B fed-batch like growth system, which applies slow in situ enzymatic glucose release from a polymer to control cell growth and protein synthesis rate. Results We were able to produce 125 mg L−1 RH corresponding to a productivity averaged over the whole process time of 3 mg (L h)−1 in shake flasks using classic single-shot IPTG induction. IPTG autoinduction resulted in a comparable volumetric RH yield of 112 mg L−1 and due to the shorter overall process time in a 1.6-fold higher productivity of 5 mg (L h)−1. In contrast, lactose autoinduction increased the volumetric yield more than 2.5-fold and the space time yield fourfold reaching 280 mg L−1 and 11.5 mg (L h)−1, respectively. Furthermore, repeated addition of booster increased RH production to 370 mg L−1, which to our knowledge is the highest RH concentration produced in E. coli to date. Conclusions The findings of this study confirm the general feasibility of the developed fed-batch based autoinduction system and provide an alternative to conventional induction systems for efficient recombinant protein production. We believe that the fed-batch based autoinduction system developed herein will favor the heterologous production of larger quantities of difficult-to-express complex enzymes to enable economical production of these kinds of proteins. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-021-01690-4.
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Affiliation(s)
- Qin Fan
- Chair of Bioprocess Engineering, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Peter Neubauer
- Chair of Bioprocess Engineering, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Matthias Gimpel
- Chair of Bioprocess Engineering, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
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6
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Megarity CF, Siritanaratkul B, Herold RA, Morello G, Armstrong FA. Electron flow between the worlds of Marcus and Warburg. J Chem Phys 2021; 153:225101. [PMID: 33317312 DOI: 10.1063/5.0024701] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Living organisms are characterized by the ability to process energy (all release heat). Redox reactions play a central role in biology, from energy transduction (photosynthesis, respiratory chains) to highly selective catalyzed transformations of complex molecules. Distance and scale are important: electrons transfer on a 1 nm scale, hydrogen nuclei transfer between molecules on a 0.1 nm scale, and extended catalytic processes (cascades) operate most efficiently when the different enzymes are under nanoconfinement (10 nm-100 nm scale). Dynamic electrochemistry experiments (defined broadly within the term "protein film electrochemistry," PFE) reveal details that are usually hidden in conventional kinetic experiments. In PFE, the enzyme is attached to an electrode, often in an innovative way, and electron-transfer reactions, individual or within steady-state catalytic flow, can be analyzed in terms of precise potentials, proton coupling, cooperativity, driving-force dependence of rates, and reversibility (a mark of efficiency). The electrochemical experiments reveal subtle factors that would have played an essential role in molecular evolution. This article describes how PFE is used to visualize and analyze different aspects of biological redox chemistry, from long-range directional electron transfer to electron/hydride (NADPH) interconversion by a flavoenzyme and finally to NADPH recycling in a nanoconfined enzyme cascade.
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Affiliation(s)
- Clare F Megarity
- Department of Chemistry, University of Oxford, Oxford OX1 3QR, United Kingdom
| | | | - Ryan A Herold
- Department of Chemistry, University of Oxford, Oxford OX1 3QR, United Kingdom
| | - Giorgio Morello
- Department of Chemistry, University of Oxford, Oxford OX1 3QR, United Kingdom
| | - Fraser A Armstrong
- Department of Chemistry, University of Oxford, Oxford OX1 3QR, United Kingdom
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7
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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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8
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Rowbotham JS, Reeve HA, Vincent KA. Hybrid Chemo-, Bio-, and Electrocatalysis for Atom-Efficient Deuteration of Cofactors in Heavy Water. ACS Catal 2021; 11:2596-2604. [PMID: 33842020 PMCID: PMC8025731 DOI: 10.1021/acscatal.0c03437] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 01/31/2021] [Indexed: 11/29/2022]
Abstract
Deuterium-labeled nicotinamide cofactors such as [4-2H]-NADH can be used as mechanistic probes in biological redox processes and offer a route to the synthesis of selectively [2H] labeled chemicals via biocatalytic reductive deuteration. Atom-efficient routes to the formation and recycling of [4-2H]-NADH are therefore highly desirable but require careful design in order to alleviate the requirement for [2H]-labeled reducing agents. In this work, we explore a suite of electrode or hydrogen gas driven catalyst systems for the generation of [4-2H]-NADH and consider their use for driving reductive deuteration reactions. Catalysts are evaluated for their chemoselectivity, stereoselectivity, and isotopic selectivity, and it is shown that inclusion of an electronically coupled NAD+-reducing enzyme delivers considerable advantages over purely metal based systems, yielding exclusively [4S-2H]-NADH. We further demonstrate the applicability of these types of [4S-2H]-NADH recycling systems for driving reductive deuteration reactions, regardless of the facioselectivity of the coupled enzyme.
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Affiliation(s)
- Jack S. Rowbotham
- Department of Chemistry,
Inorganic Chemistry Laboratory, University
of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Holly A. Reeve
- Department of Chemistry,
Inorganic Chemistry Laboratory, University
of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Kylie A. Vincent
- Department of Chemistry,
Inorganic Chemistry Laboratory, University
of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
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9
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Preissler J, Reeve HA, Zhu T, Nicholson J, Urata K, Lauterbach L, Wong LL, Vincent KA, Lenz O. Dihydrogen‐Driven NADPH Recycling in Imine Reduction and P450‐Catalyzed Oxidations Mediated by an Engineered O
2
‐Tolerant Hydrogenase. ChemCatChem 2020. [DOI: 10.1002/cctc.202000763] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Janina Preissler
- Institute of Chemistry, Biophysical Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
| | - Holly A. Reeve
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Tianze Zhu
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Jake Nicholson
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Kouji Urata
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Lars Lauterbach
- Institute of Chemistry, Biophysical Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
| | - Luet L. Wong
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Kylie A. Vincent
- Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR UK
| | - Oliver Lenz
- Institute of Chemistry, Biophysical Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
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10
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Al-Shameri A, Willot SJP, Paul CE, Hollmann F, Lauterbach L. H 2 as a fuel for flavin- and H 2O 2-dependent biocatalytic reactions. Chem Commun (Camb) 2020; 56:9667-9670. [PMID: 32696786 DOI: 10.1039/d0cc03229h] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The soluble hydrogenase from Ralstonia eutropha provides an atom efficient regeneration system for reduced flavin cofactors using H2 as an electron source. We demonstrated this system for highly selective ene-reductase-catalyzed C[double bond, length as m-dash]C-double bond reductions and monooxygenase-catalyzed epoxidation. Reactions were expanded to aerobic conditions to supply H2O2 for peroxygenase-catalyzed hydroxylations.
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Affiliation(s)
- Ammar Al-Shameri
- Institute of Chemistry, Technische Universität Berlin, Strasse des 17, Juni 135, 10623 Berlin, Germany.
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11
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Structure: Function Studies of the Cytosolic, Mo- and NAD+-Dependent Formate Dehydrogenase from Cupriavidus necator. INORGANICS 2020. [DOI: 10.3390/inorganics8070041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Here, we report recent progress our laboratories have made in understanding the maturation and reaction mechanism of the cytosolic and NAD+-dependent formate dehydrogenase from Cupriavidus necator. Our recent work has established that the enzyme is fully capable of catalyzing the reverse of the physiological reaction, namely, the reduction of CO2 to formate using NADH as a source of reducing equivalents. The steady-state kinetic parameters in the forward and reverse directions are consistent with the expected Haldane relationship. The addition of an NADH-regenerating system consisting of glucose and glucose dehydrogenase increases the yield of formate approximately 10-fold. This work points to possible ways of optimizing the reverse of the enzyme’s physiological reaction with commercial potential as an effective means of CO2 remediation. New insight into the maturation of the enzyme comes from the recently reported structure of the FdhD sulfurase. In E. coli, FdhD transfers a catalytically essential sulfur to the maturing molybdenum cofactor prior to insertion into the apoenzyme of formate dehydrogenase FdhF, which has high sequence similarity to the molybdenum-containing domain of the C. necator FdsA. The FdhD structure suggests that the molybdenum cofactor may first be transferred from the sulfurase to the C-terminal cap domain of apo formate dehydrogenase, rather than being transferred directly to the body of the apoenzyme. Closing of the cap domain over the body of the enzymes delivers the Mo-cofactor into the active site, completing the maturation of formate dehydrogenase. The structural and kinetic characterization of the NADH reduction of the FdsBG subcomplex of the enzyme provides further insights in reversing of the formate dehydrogenase reaction. Most notably, we observe the transient formation of a neutral semiquinone FMNH·, a species that has not been observed previously with holoenzyme. After initial reduction of the FMN of FdsB by NADH to the hydroquinone (with a kred of 680 s−1 and Kd of 190 µM), one electron is rapidly transferred to the Fe2S2 cluster of FdsG, leaving FMNH·. The Fe4S4 cluster of FdsB does not become reduced in the process. These results provide insight into the function not only of the C. necator formate dehydrogenase but also of other members of the NADH dehydrogenase superfamily of enzymes to which it belongs.
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12
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Al‐Shameri A, Petrich M, junge Puring K, Apfel U, Nestl BM, Lauterbach L. Künstliche Enzymkaskaden angetrieben mittels elektrischer Energie. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ammar Al‐Shameri
- Technische Universität BerlinInstitut für Chemie Strasse des 17. Juni 135 10623 Berlin Deutschland
| | - Marie‐Christine Petrich
- Technische Universität BerlinInstitut für Chemie Strasse des 17. Juni 135 10623 Berlin Deutschland
| | - Kai junge Puring
- Ruhr-Universität BochumAnorganische Chemie Universitaetsstrasse 150 44780 Bochum Deutschland
- Fraunhofer UMSICHT Osterfelder Strasse 3 46047 Oberhausen Deutschland
| | - Ulf‐Peter Apfel
- Ruhr-Universität BochumAnorganische Chemie Universitaetsstrasse 150 44780 Bochum Deutschland
- Fraunhofer UMSICHT Osterfelder Strasse 3 46047 Oberhausen Deutschland
| | - Bettina M. Nestl
- Universität StuttgartInstitut für Biochemie und Technische BiochemieAbteilung für Technische Biochemie Allmandring 31 70569 Stuttgart Deutschland
| | - Lars Lauterbach
- Technische Universität BerlinInstitut für Chemie Strasse des 17. Juni 135 10623 Berlin Deutschland
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13
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Artz JH, Tokmina-Lukaszewska M, Mulder DW, Lubner CE, Gutekunst K, Appel J, Bothner B, Boehm M, King PW. The structure and reactivity of the HoxEFU complex from the cyanobacterium Synechocystis sp. PCC 6803. J Biol Chem 2020; 295:9445-9454. [PMID: 32409585 PMCID: PMC7363133 DOI: 10.1074/jbc.ra120.013136] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/11/2020] [Indexed: 11/19/2022] Open
Abstract
Cyanobacterial Hox is a [NiFe] hydrogenase that consists of the hydrogen (H2)-activating subunits HoxYH, which form a complex with the HoxEFU assembly to mediate reactions with soluble electron carriers like NAD(P)H and ferredoxin (Fdx), thereby coupling photosynthetic electron transfer to energy-transforming catalytic reactions. Researchers studying the HoxEFUYH complex have observed that HoxEFU can be isolated independently of HoxYH, leading to the hypothesis that HoxEFU is a distinct functional subcomplex rather than an artifact of Hox complex isolation. Moreover, outstanding questions about the reactivity of Hox with natural substrates and the site(s) of substrate interactions and coupling of H2, NAD(P)H, and Fdx remain to be resolved. To address these questions, here we analyzed recombinantly produced HoxEFU by electron paramagnetic resonance spectroscopy and kinetic assays with natural substrates. The purified HoxEFU subcomplex catalyzed electron transfer reactions among NAD(P)H, flavodoxin, and several ferredoxins, thus functioning in vitro as a shuttle among different cyanobacterial pools of reducing equivalents. Both Fdx1-dependent reductions of NAD+ and NADP+ were cooperative. HoxEFU also catalyzed the flavodoxin-dependent reduction of NAD(P)+, Fdx2-dependent oxidation of NADH and Fdx4- and Fdx11-dependent reduction of NAD+. MS-based mapping identified an Fdx1-binding site at the junction of HoxE and HoxF, adjacent to iron-sulfur (FeS) clusters in both subunits. Overall, the reactivity of HoxEFU observed here suggests that it functions in managing peripheral electron flow from photosynthetic electron transfer, findings that reveal detailed insights into how ubiquitous cellular components may be used to allocate energy flow into specific bioenergetic products.
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Affiliation(s)
- Jacob H Artz
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
| | | | - David W Mulder
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
| | - Carolyn E Lubner
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
| | | | - Jens Appel
- Botanical Institute, Christian-Albrechts-University, Kiel, Germany
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Marko Boehm
- Botanical Institute, Christian-Albrechts-University, Kiel, Germany
| | - Paul W King
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
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14
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Young T, Niks D, Hakopian S, Tam TK, Yu X, Hille R, Blaha GM. Crystallographic and kinetic analyses of the FdsBG subcomplex of the cytosolic formate dehydrogenase FdsABG from Cupriavidus necator. J Biol Chem 2020; 295:6570-6585. [PMID: 32249211 PMCID: PMC7212643 DOI: 10.1074/jbc.ra120.013264] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 03/30/2020] [Indexed: 01/07/2023] Open
Abstract
Formate oxidation to carbon dioxide is a key reaction in one-carbon compound metabolism, and its reverse reaction represents the first step in carbon assimilation in the acetogenic and methanogenic branches of many anaerobic organisms. The molybdenum-containing dehydrogenase FdsABG is a soluble NAD+-dependent formate dehydrogenase and a member of the NADH dehydrogenase superfamily. Here, we present the first structure of the FdsBG subcomplex of the cytosolic FdsABG formate dehydrogenase from the hydrogen-oxidizing bacterium Cupriavidus necator H16 both with and without bound NADH. The structures revealed that the two iron-sulfur clusters, Fe4S4 in FdsB and Fe2S2 in FdsG, are closer to the FMN than they are in other NADH dehydrogenases. Rapid kinetic studies and EPR measurements of rapid freeze-quenched samples of the NADH reduction of FdsBG identified a neutral flavin semiquinone, FMNH•, not previously observed to participate in NADH-mediated reduction of the FdsABG holoenzyme. We found that this semiquinone forms through the transfer of one electron from the fully reduced FMNH-, initially formed via NADH-mediated reduction, to the Fe2S2 cluster. This Fe2S2 cluster is not part of the on-path chain of iron-sulfur clusters connecting the FMN of FdsB with the active-site molybdenum center of FdsA. According to the NADH-bound structure, the nicotinamide ring stacks onto the re-face of the FMN. However, NADH binding significantly reduced the electron density for the isoalloxazine ring of FMN and induced a conformational change in residues of the FMN-binding pocket that display peptide-bond flipping upon NAD+ binding in proper NADH dehydrogenases.
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Affiliation(s)
- Tynan Young
- Department of Biochemistry, University of California, Riverside, California 92521
| | - Dimitri Niks
- Department of Biochemistry, University of California, Riverside, California 92521
| | - Sheron Hakopian
- Department of Biochemistry, University of California, Riverside, California 92521
| | - Timothy K. Tam
- Department of Biochemistry, University of California, Riverside, California 92521
| | - Xuejun Yu
- Department of Biochemistry, University of California, Riverside, California 92521
| | - Russ Hille
- Department of Biochemistry, University of California, Riverside, California 92521, To whom correspondence may be addressed:
Dept. of Biochemistry, University of California, Riverside, 900 University Ave., Boyce Hall 2404, Riverside, CA 92521. Tel.:
951-827-6354; E-mail:
| | - Gregor M. Blaha
- Department of Biochemistry, University of California, Riverside, California 92521, To whom correspondence may be addressed:
Dept. of Biochemistry, University of California, Riverside, 900 University Ave., Boyce Hall 5489, Riverside, CA 92521. Tel.:
951-827-3832; Fax:
951-827-4294; E-mail:
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15
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Al-Shameri A, Petrich MC, Junge Puring K, Apfel UP, Nestl BM, Lauterbach L. Powering Artificial Enzymatic Cascades with Electrical Energy. Angew Chem Int Ed Engl 2020; 59:10929-10933. [PMID: 32202370 PMCID: PMC7318245 DOI: 10.1002/anie.202001302] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/06/2020] [Indexed: 11/08/2022]
Abstract
We have developed a scalable platform that employs electrolysis for an in vitro synthetic enzymatic cascade in a continuous flow reactor. Both H2 and O2 were produced by electrolysis and transferred through a gas-permeable membrane into the flow system. The membrane enabled the separation of the electrolyte from the biocatalysts in the flow system, where H2 and O2 served as electron mediators for the biocatalysts. We demonstrate the production of methylated N-heterocycles from diamines with up to 99 % product formation as well as excellent regioselective labeling with stable isotopes. Our platform can be applied for a broad panel of oxidoreductases to exploit electrical energy for the synthesis of fine chemicals.
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Affiliation(s)
- Ammar Al-Shameri
- Technical University of Berlin, Institute of Chemistry, Strasse des 17. Juni 135, 10623, Berlin, Germany
| | - Marie-Christine Petrich
- Technical University of Berlin, Institute of Chemistry, Strasse des 17. Juni 135, 10623, Berlin, Germany
| | - Kai Junge Puring
- Ruhr-University Bochum, Inorganic Chemistry, Universitaetsstrasse 150, 44780, Bochum, Germany.,Fraunhofer UMSICHT, Osterfelder Strasse 3, 46047, Oberhausen, Germany
| | - Ulf-Peter Apfel
- Ruhr-University Bochum, Inorganic Chemistry, Universitaetsstrasse 150, 44780, Bochum, Germany.,Fraunhofer UMSICHT, Osterfelder Strasse 3, 46047, Oberhausen, Germany
| | - Bettina M Nestl
- Universitaet Stuttgart, Institute of Biochemistry and Technical Biochemistry, Department of Technical Biochemistry, Allmandring 31, 70569, Stuttgart, Germany
| | - Lars Lauterbach
- Technical University of Berlin, Institute of Chemistry, Strasse des 17. Juni 135, 10623, Berlin, Germany
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16
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Direct Electron Transfer-Type Bioelectrocatalysis of Redox Enzymes at Nanostructured Electrodes. Catalysts 2020. [DOI: 10.3390/catal10020236] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Direct electron transfer (DET)-type bioelectrocatalysis, which couples the electrode reactions and catalytic functions of redox enzymes without any redox mediator, is one of the most intriguing subjects that has been studied over the past few decades in the field of bioelectrochemistry. In order to realize the DET-type bioelectrocatalysis and improve the performance, nanostructures of the electrode surface have to be carefully tuned for each enzyme. In addition, enzymes can also be tuned by the protein engineering approach for the DET-type reaction. This review summarizes the recent progresses in this field of the research while considering the importance of nanostructure of electrodes as well as redox enzymes. This review also describes the basic concepts and theoretical aspects of DET-type bioelectrocatalysis, the significance of nanostructures as scaffolds for DET-type reactions, protein engineering approaches for DET-type reactions, and concepts and facts of bidirectional DET-type reactions from a cross-disciplinary viewpoint.
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17
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Megarity CF, Siritanaratkul B, Cheng B, Morello G, Wan L, Sills AJ, Heath RS, Turner NJ, Armstrong FA. Electrified Nanoconfined Biocatalysis with Rapid Cofactor Recycling. ChemCatChem 2019. [DOI: 10.1002/cctc.201901245] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Clare F. Megarity
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | | | - Beichen Cheng
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Giorgio Morello
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Lei Wan
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Adam J. Sills
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Rachel S. Heath
- School of ChemistryManchester Institute of BiotechnologyUniversity of Manchester 131 Princess Street Manchester M1 7DN UK
| | - Nicholas J. Turner
- School of ChemistryManchester Institute of BiotechnologyUniversity of Manchester 131 Princess Street Manchester M1 7DN UK
| | - Fraser A. Armstrong
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
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18
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Huston S, Collins J, Sun F, Zhang T, Vaden TD, Zhang YHP, Fu J. An activity transition from NADH dehydrogenase to NADH oxidase during protein denaturation. Biotechnol Appl Biochem 2017; 65:286-293. [PMID: 28881090 DOI: 10.1002/bab.1607] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 08/14/2017] [Accepted: 09/02/2017] [Indexed: 11/07/2022]
Abstract
A decrease in the specific activity of an enzyme is commonly observed when the enzyme is inappropriately handled or is stored over an extended period. Here, we reported a functional transition of an FMN-bound diaphorase (FMN-DI) that happened during the long-term storage process. It was found that FMN-DI did not simply lose its β-nicotinamide adenine diphosphate (NADH) dehydrogenase activity after a long-time storage, but obtained a new enzyme activity of NADH oxidase. Further mechanistic studies suggested that the alteration of the binding strength of an FMN cofactor with a DI protein could be responsible for this functional switch of the enzyme.
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Affiliation(s)
- Scott Huston
- Department of Chemistry, Rutgers University-Camden, Camden, NJ, USA
| | - John Collins
- Department of Chemistry, Rutgers University-Camden, Camden, NJ, USA
| | - Fangfang Sun
- Cell Free Bioinnovations Inc., Blacksburg, VA, USA
| | - Ting Zhang
- Department of Chemistry, Rutgers University-Camden, Camden, NJ, USA
| | - Timothy D Vaden
- Department of Chemistry and Biochemistry, Rowan University, Glassboro, NJ, USA
| | - Y-H Percival Zhang
- Cell Free Bioinnovations Inc., Blacksburg, VA, USA
- Department of Biological Systems Engineering, Virginia Tech, VA, USA
| | - Jinglin Fu
- Department of Chemistry, Rutgers University-Camden, Camden, NJ, USA
- Center for Computational and Integrative Biology, Rutgers University-Camden, Camden, NJ, USA
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19
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Enzymatic and spectroscopic properties of a thermostable [NiFe]‑hydrogenase performing H 2-driven NAD +-reduction in the presence of O 2. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1859:8-18. [PMID: 28970007 DOI: 10.1016/j.bbabio.2017.09.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/17/2017] [Accepted: 09/28/2017] [Indexed: 12/18/2022]
Abstract
Biocatalysts that mediate the H2-dependent reduction of NAD+ to NADH are attractive from both a fundamental and applied perspective. Here we present the first biochemical and spectroscopic characterization of an NAD+-reducing [NiFe]‑hydrogenase that sustains catalytic activity at high temperatures and in the presence of O2, which usually acts as an inhibitor. We isolated and sequenced the four structural genes, hoxFUYH, encoding the soluble NAD+-reducing [NiFe]‑hydrogenase (SH) from the thermophilic betaproteobacterium, Hydrogenophilus thermoluteolus TH-1T (Ht). The HtSH was recombinantly overproduced in a hydrogenase-free mutant of the well-studied, H2-oxidizing betaproteobacterium Ralstonia eutropha H16 (Re). The enzyme was purified and characterized with various biochemical and spectroscopic techniques. Highest H2-mediated NAD+ reduction activity was observed at 80°C and pH6.5, and catalytic activity was found to be sustained at low O2 concentrations. Infrared spectroscopic analyses revealed a spectral pattern for as-isolated HtSH that is remarkably different from those of the closely related ReSH and other [NiFe]‑hydrogenases. This indicates an unusual configuration of the oxidized catalytic center in HtSH. Complementary electron paramagnetic resonance spectroscopic analyses revealed spectral signatures similar to related NAD+-reducing [NiFe]‑hydrogenases. This study lays the groundwork for structural and functional analyses of the HtSH as well as application of this enzyme for H2-driven cofactor recycling under oxic conditions at elevated temperatures.
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20
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Reeve HA, Ash PA, Park H, Huang A, Posidias M, Tomlinson C, Lenz O, Vincent KA. Enzymes as modular catalysts for redox half-reactions in H2-powered chemical synthesis: from biology to technology. Biochem J 2017; 474:215-230. [PMID: 28062838 PMCID: PMC5298933 DOI: 10.1042/bcj20160513] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 11/17/2022]
Abstract
The present study considers the ways in which redox enzyme modules are coupled in living cells for linking reductive and oxidative half-reactions, and then reviews examples in which this concept can be exploited technologically in applications of coupled enzyme pairs. We discuss many examples in which enzymes are interfaced with electronically conductive particles to build up heterogeneous catalytic systems in an approach which could be termed synthetic biochemistry We focus on reactions involving the H+/H2 redox couple catalysed by NiFe hydrogenase moieties in conjunction with other biocatalysed reactions to assemble systems directed towards synthesis of specialised chemicals, chemical building blocks or bio-derived fuel molecules. We review our work in which this approach is applied in designing enzyme-modified particles for H2-driven recycling of the nicotinamide cofactor NADH to provide a clean cofactor source for applications of NADH-dependent enzymes in chemical synthesis, presenting a combination of published and new work on these systems. We also consider related photobiocatalytic approaches for light-driven production of chemicals or H2 as a fuel. We emphasise the techniques available for understanding detailed catalytic properties of the enzymes responsible for individual redox half-reactions, and the importance of a fundamental understanding of the enzyme characteristics in enabling effective applications of redox biocatalysis.
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Affiliation(s)
- Holly A Reeve
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K
| | - Philip A Ash
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K
| | - HyunSeo Park
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K
| | - Ailun Huang
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K
| | - Michalis Posidias
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K
| | - Chloe Tomlinson
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K
| | - Oliver Lenz
- Department of Chemistry, Technische Universität Berlin, Berlin 10623, Germany
| | - Kylie A Vincent
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, U.K.
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21
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Shipovskov S, Bonamore A, Boffi A, Ferapontova EE. Electrocatalytic interconversion of NADH and NAD(+) by Escherichia coli flavohemoglobin. Chem Commun (Camb) 2016; 51:16096-8. [PMID: 26389555 DOI: 10.1039/c5cc06317e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
E. coli flavohemoglobin, oriented at electrodes via amphiphilic polymyxin B, electrocatalytically interconverts NADH and NAD(+) at its heme potentials operating as an electron transfer relay between the electrode and the protein FAD, where NADH/NAD(+) is transformed. The results are crucial for the development of NAD(+)-dependent bioelectrodes for biosynthesis, biosensors and biofuel cells.
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Affiliation(s)
- S Shipovskov
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.
| | - A Bonamore
- Department of Biochemical Sciences and CNR Institute of Molecular Biology and Pathology, University "La Sapienza", 00185 Rome, Italy
| | - A Boffi
- Department of Biochemical Sciences and CNR Institute of Molecular Biology and Pathology, University "La Sapienza", 00185 Rome, Italy
| | - E E Ferapontova
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.
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22
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Collins J, Zhang T, Huston S, Sun F, Zhang YHP, Fu J. A Hidden Transhydrogen Activity of a FMN-Bound Diaphorase under Anaerobic Conditions. PLoS One 2016; 11:e0154865. [PMID: 27145082 PMCID: PMC4856307 DOI: 10.1371/journal.pone.0154865] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 04/20/2016] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Redox cofactors of NADH/NADPH participate in many cellular metabolic pathways for facilitating the electron transfer from one molecule to another in redox reactions. Transhydrogenase plays an important role in linking catabolism and anabolism, regulating the ratio of NADH/NADPH in cells. The cytoplasmic transhydrogenases could be useful to engineer synthetic biochemical pathways for the production of high-value chemicals and biofuels. METHODOLOGY/PRINCIPAL FINDINGS A transhydrogenase activity was discovered for a FMN-bound diaphorase (DI) from Geobacillus stearothermophilus under anaerobic conditions. The DI-catalyzed hydride exchange were monitored and characterized between a NAD(P)H and a thio-modified NAD+ analogue. This new function of DI was demonstrated to transfer a hydride from NADPH to NAD+ that was consumed by NAD-specific lactate dehydrogenase and malic dehydrogenase. CONCLUSIONS/SIGNIFICANCE We discover a novel transhydrogenase activity of a FMN-DI by stabilizing the reduced state of FMNH2 under anaerobic conditions. FMN-DI was demonstrated to catalyze the hydride transfer between NADPH and NAD+. In the future, it may be possible to incorporate this FMN-DI into synthetic enzymatic pathways for balancing NADH generation and NADPH consumption for anaerobic production of biofuels and biochemicals.
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Affiliation(s)
- John Collins
- Department of Chemistry, Rutgers University-Camden, Camden, New Jersey 08102, United States of America
| | - Ting Zhang
- Department of Chemistry, Rutgers University-Camden, Camden, New Jersey 08102, United States of America
| | - Scott Huston
- Department of Chemistry, Rutgers University-Camden, Camden, New Jersey 08102, United States of America
| | - Fangfang Sun
- Cell Free Bioinnovations Inc., Blacksburg, Virginia 24060, United States of America
| | - Y.-H. Percival Zhang
- Cell Free Bioinnovations Inc., Blacksburg, Virginia 24060, United States of America
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States of America
| | - Jinglin Fu
- Department of Chemistry, Rutgers University-Camden, Camden, New Jersey 08102, United States of America
- Center for Computational and Integrative Biology, Rutgers University-Camden, Camden, New Jersey 08102, United States of America
- * E-mail:
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23
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Reeve HA, Lauterbach L, Lenz O, Vincent KA. Enzyme-Modified Particles for Selective Biocatalytic Hydrogenation by Hydrogen-Driven NADH Recycling. ChemCatChem 2015; 7:3480-3487. [PMID: 26613009 PMCID: PMC4648031 DOI: 10.1002/cctc.201500766] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 08/17/2015] [Indexed: 12/12/2022]
Abstract
We describe a new approach to selective H2-driven hydrogenation that exploits a sequence of enzymes immobilised on carbon particles. We used a catalyst system that comprised alcohol dehydrogenase, hydrogenase and an NAD+ reductase on carbon black to demonstrate a greater than 98 % conversion of acetophenone to phenylethanol. Oxidation of H2 by the hydrogenase provides electrons through the carbon for NAD+ reduction to recycle the NADH cofactor required by the alcohol dehydrogenase. This biocatalytic system operates over the pH range 6-8 or in un-buffered water, and can function at low concentrations of the cofactor (10 μm NAD+) and at H2 partial pressures below 1 bar. Total turnover numbers >130 000 during acetophenone reduction indicate high enzyme stability, and the immobilised enzymes can be recovered by a simple centrifugation step and re-used several times. This offers a route to convenient, atom-efficient operation of NADH-dependent oxidoreductases for selective hydrogenation catalysis.
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Affiliation(s)
- Holly A Reeve
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory South Parks Road, Oxford, OX1 3QR (UK) E-mail:
| | - Lars Lauterbach
- Institute of Chemistry, Technische Universität Berlin Strasse des 17. Juni 135, 10623, Berlin (Germany)
| | - Oliver Lenz
- Institute of Chemistry, Technische Universität Berlin Strasse des 17. Juni 135, 10623, Berlin (Germany)
| | - Kylie A Vincent
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory South Parks Road, Oxford, OX1 3QR (UK) E-mail:
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24
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Schiffels J, Selmer T. A flexible toolbox to study protein-assisted metalloenzyme assembly in vitro. Biotechnol Bioeng 2015; 112:2360-72. [PMID: 25994231 DOI: 10.1002/bit.25658] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 05/11/2015] [Indexed: 11/06/2022]
Abstract
A number of metalloenzymes harbor unique cofactors, which are incorporated into the apo-enzymes via protein-assisted maturation. In the case of [NiFe]-hydrogenases, minimally seven maturation factors (HypABCDEF and a specific endopeptidase) are involved, making these enzymes an excellent example for studying metallocenter assembly in general. Here, we describe an innovative toolbox to study maturation involving multiple putative gene products. The two core elements of the system are a modular, combinatorial cloning system and a cell-free maturation system, which is based on recombinant Escherichia coli extracts and/or purified maturases. Taking maturation of the soluble, oxygen-tolerant [NiFe]-hydrogenase (SH) from Cupriavidus necator as an example, the capacities of the toolbox are illustrated. In total 18 genes from C. necator were analyzed, including four SH-structural genes, the SH-dedicated hyp-genes and a second set of hyp-genes putatively involved in maturation of the Actinobacterium-like hydrogenase (AH). The two hyp-sets were either expressed in their entirety from single vectors or split into functional modules, which enabled flexible approaches to investigate limitations, specificities and the capabilities of individual constituents to functionally substitute each other. Affinity-tagged Hyp-Proteins were used in pull-down experiments to demonstrate direct interactions between dedicated or non-related constituents. The dedicated Hyp-set from C. necator exhibited the highest maturation efficiency in vitro. Constituents of non-related maturation machineries were found to interact with and to accomplish partial activation of SH. In contrast to homologues of the Hyp-family, omission of the SH-specific endopeptidase HoxW completely abolished in vitro maturation. We detected stoichiometric imbalances inside the recombinant production system, which point to limitations by the cyanylation complex HypEF and the premature subunit HoxH. Purification of HoxW revealed strong indications for the presence of a putative [4Fe-4S]-cluster, which is unique among this class of maturases. Results are discussed in the context of [NiFe]-hydrogenase maturation, and in light of the capacity of the novel toolbox.
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Affiliation(s)
- Johannes Schiffels
- From the Aachen University of Applied Sciences, Campus Juelich, Department of Chemistry and Biotechnology, Heinrich-Mussmann-Str. 1, D-52428 Juelich, Germany
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25
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Karstens K, Wahlefeld S, Horch M, Grunzel M, Lauterbach L, Lendzian F, Zebger I, Lenz O. Impact of the iron-sulfur cluster proximal to the active site on the catalytic function of an O2-tolerant NAD(+)-reducing [NiFe]-hydrogenase. Biochemistry 2015; 54:389-403. [PMID: 25517969 DOI: 10.1021/bi501347u] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The soluble NAD(+)-reducing hydrogenase (SH) from Ralstonia eutropha H16 belongs to the O2-tolerant subtype of pyridine nucleotide-dependent [NiFe]-hydrogenases. To identify molecular determinants for the O2 tolerance of this enzyme, we introduced single amino acids exchanges in the SH small hydrogenase subunit. The resulting mutant strains and proteins were investigated with respect to their physiological, biochemical, and spectroscopic properties. Replacement of the four invariant conserved cysteine residues, Cys41, Cys44, Cys113, and Cys179, led to unstable protein, strongly supporting their involvement in the coordination of the iron-sulfur cluster proximal to the catalytic [NiFe] center. The Cys41Ser exchange, however, resulted in an SH variant that displayed up to 10% of wild-type activity, suggesting that the coordinating role of Cys41 might be partly substituted by the nearby Cys39 residue, which is present only in O2-tolerant pyridine nucleotide-dependent [NiFe]-hydrogenases. Indeed, SH variants carrying glycine, alanine, or serine in place of Cys39 showed increased O2 sensitivity compared to that of the wild-type enzyme. Substitution of further amino acids typical for O2-tolerant SH representatives did not greatly affect the H2-oxidizing activity in the presence of O2. Remarkably, all mutant enzymes investigated by electron paramagnetic resonance spectroscopy did not reveal significant spectral changes in relation to wild-type SH, showing that the proximal iron-sulfur cluster does not contribute to the wild-type spectrum. Interestingly, exchange of Trp42 by serine resulted in a completely redox-inactive [NiFe] site, as revealed by infrared spectroscopy and H2/D(+) exchange experiments. The possible role of this residue in electron and/or proton transfer is discussed.
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Affiliation(s)
- Katja Karstens
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin , Chausseestr. 117, 10115 Berlin, Germany
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26
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Lonsdale TH, Lauterbach L, Honda Malca S, Nestl BM, Hauer B, Lenz O. H2-driven biotransformation of n-octane to 1-octanol by a recombinant Pseudomonas putida strain co-synthesizing an O2-tolerant hydrogenase and a P450 monooxygenase. Chem Commun (Camb) 2015; 51:16173-5. [DOI: 10.1039/c5cc06078h] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A bacterial whole-cell system was designed for hydroxylation of n-octane to 1-octanol at the expense of molecular hydrogen and oxygen.
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Affiliation(s)
- Thomas H. Lonsdale
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
- Department of Chemistry
| | - Lars Lauterbach
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Sumire Honda Malca
- Institute of Technical Biochemistry
- Universität Stuttgart
- Stuttgart
- Germany
| | - Bettina M. Nestl
- Institute of Technical Biochemistry
- Universität Stuttgart
- Stuttgart
- Germany
| | - Bernhard Hauer
- Institute of Technical Biochemistry
- Universität Stuttgart
- Stuttgart
- Germany
| | - Oliver Lenz
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
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27
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Sosna M, Fapyane D, Ferapontova EE. Reconstitution of peroxidase onto hemin-terminated alkanethiol self-assembled monolayers on gold. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.06.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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28
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Singh K, Blanford CF. Electrochemical Quartz Crystal Microbalance with Dissipation Monitoring: A Technique to Optimize Enzyme Use in Bioelectrocatalysis. ChemCatChem 2014. [DOI: 10.1002/cctc.201300900] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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29
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Affiliation(s)
- Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Hideaki Ogata
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Edward Reijerse
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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30
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Lauterbach L, Lenz O. Catalytic production of hydrogen peroxide and water by oxygen-tolerant [NiFe]-hydrogenase during H2 cycling in the presence of O2. J Am Chem Soc 2013; 135:17897-905. [PMID: 24180286 DOI: 10.1021/ja408420d] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hydrogenases control the H2-related metabolism in many microbes. Most of these enzymes are prone to immediate inactivation by O2. However, a few members of the subclass of [NiFe]-hydrogenases are able to convert H2 into protons and electrons even in the presence of O2, making them attractive for biotechnological application. Recent studies on O2-tolerant membrane-bound hydrogenases indicate that the mechanism of O2 tolerance relies on their capability to completely reduce O2 with four electrons to harmless water. In order to verify this hypothesis, we probed the O2 reduction capacity of the soluble, NAD(+)-reducing [NiFe]-hydrogenase (SH) from Ralstonia eutropha H16. A newly established, homologous overexpression allowed the purification of up to 90 mg of homogeneous and highly active enzyme from 10 g of cell material. We showed that the SH produces trace amounts of superoxide in the course of H2-driven NAD(+) reduction in the presence of O2. However, the major products of the SH-mediated oxidase activity was in fact hydrogen peroxide and water as shown by the mass spectrometric detection of H2(18)O formed from H2 and isotopically labeled (18)O2. Water release was also observed when the enzyme was incubated with NADH and (18)O2, demonstrating the importance of reverse electron flow to the [NiFe] active site for O2 reduction. A comparison of the turnover rates for H2 and O2 revealed that in the presence of twice the ambient level of O2, up to 3% of the electrons generated through H2 oxidation serve as "health insurance" and are reused for O2 reduction.
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Affiliation(s)
- Lars Lauterbach
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin , Chausseestrasse 117, 10115 Berlin, Germany
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31
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Hartmann T, Leimkühler S. The oxygen-tolerant and NAD+-dependent formate dehydrogenase from Rhodobacter capsulatus is able to catalyze the reduction of CO2 to formate. FEBS J 2013; 280:6083-96. [PMID: 24034888 DOI: 10.1111/febs.12528] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 09/08/2013] [Accepted: 09/10/2013] [Indexed: 11/27/2022]
Abstract
The formate dehydrogenase from Rhodobacter capsulatus (RcFDH) is an oxygen-tolerant protein with an (αβγ)2 subunit composition that is localized in the cytoplasm. It belongs to the group of metal and NAD(+)-dependent FDHs with the coordination of a molybdenum cofactor, four [Fe4S4] clusters and one [Fe2S2] cluster associated with the α-subunit, one [Fe4S4] cluster and one FMN bound to the β-subunit, and one [Fe2S2] cluster bound to the γ-subunit. RcFDH was heterologously expressed in Escherichia coli and characterized. Cofactor analysis showed that the bis-molybdopterin guanine dinucleotide cofactor is bound to the FdsA subunit containing a cysteine ligand at the active site. A turnover rate of 2189 min(-1) with formate as substrate was determined. The back reaction for the reduction of CO2 was catalyzed with a k(cat) of 89 min(-1). The preference for formate oxidation shows an energy barrier for CO2 reduction of the enzyme. Furthermore, the FMN-containing and [Fe4S4]-containing β-subunit together with the [Fe2S2]-containing γ-subunit forms a diaphorase unit with activities for both NAD(+) reduction and NADH oxidation. In addition to the structural genes fdsG, fdsB, and fdsA, the fds operon in R. capsulatus contains the fdsC and fdsD genes. Expression studies showed that RcFDH is only active when both FdsC and FdsD are present. Both proteins are proposed to be involved in bis-molybdopterin guanine dinucleotide modification and insertion into RcFDH.
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Affiliation(s)
- Tobias Hartmann
- Department of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Germany
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32
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Schiffels J, Pinkenburg O, Schelden M, Aboulnaga EHAA, Baumann MEM, Selmer T. An innovative cloning platform enables large-scale production and maturation of an oxygen-tolerant [NiFe]-hydrogenase from Cupriavidus necator in Escherichia coli. PLoS One 2013; 8:e68812. [PMID: 23861944 PMCID: PMC3702609 DOI: 10.1371/journal.pone.0068812] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Accepted: 05/31/2013] [Indexed: 11/18/2022] Open
Abstract
Expression of multiple heterologous genes in a dedicated host is a prerequisite for approaches in synthetic biology, spanning from the production of recombinant multiprotein complexes to the transfer of tailor-made metabolic pathways. Such attempts are often exacerbated, due in most cases to a lack of proper directional, robust and readily accessible genetic tools. Here, we introduce an innovative system for cloning and expression of multiple genes in Escherichia coli BL21 (DE3). Using the novel methodology, genes are equipped with individual promoters and terminators and subsequently assembled. The resulting multiple gene cassettes may either be placed in one vector or alternatively distributed among a set of compatible plasmids. We demonstrate the effectiveness of the developed tool by production and maturation of the NAD(+)reducing soluble [NiFe]-hydrogenase (SH) from Cupriavidus necator H16 (formerly Ralstonia eutropha H16) in E. coli BL21Star™ (DE3). The SH (encoded in hoxFUYHI) was successfully matured by co-expression of a dedicated set of auxiliary genes, comprising seven hyp genes (hypC1D1E1A2B2F2X) along with hoxW, which encodes a specific endopeptidase. Deletion of genes involved in SH maturation reduced maturation efficiency substantially. Further addition of hoxN1, encoding a high-affinity nickel permease from C. necator, considerably increased maturation efficiency in E. coli. Carefully balanced growth conditions enabled hydrogenase production at high cell-densities, scoring mg·(Liter culture)(-1) yields of purified functional SH. Specific activities of up to 7.2±1.15 U·mg(-1) were obtained in cell-free extracts, which is in the range of the highest activities ever determined in C. necator extracts. The recombinant enzyme was isolated in equal purity and stability as previously achieved with the native form, yielding ultrapure preparations with anaerobic specific activities of up to 230 U·mg(-1). Owing to the combinatorial power exhibited by the presented cloning platform, the system might represent an important step towards new routes in synthetic biology.
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Affiliation(s)
- Johannes Schiffels
- Department of Chemistry and Biotechnology, Aachen University of Applied Sciences, Juelich, Germany
| | - Olaf Pinkenburg
- Institute for Immunology, Biomedical Research Centre (BMFZ), Philipps University of Marburg, Marburg (Lahn), Germany
| | - Maximilian Schelden
- Department of Chemistry and Biotechnology, Aachen University of Applied Sciences, Juelich, Germany
| | | | - Marcus E. M. Baumann
- Department of Chemistry and Biotechnology, Aachen University of Applied Sciences, Juelich, Germany
| | - Thorsten Selmer
- Department of Chemistry and Biotechnology, Aachen University of Applied Sciences, Juelich, Germany
- * E-mail:
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33
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Lauterbach L, Lenz O, Vincent KA. H₂-driven cofactor regeneration with NAD(P)⁺-reducing hydrogenases. FEBS J 2013; 280:3058-68. [PMID: 23497170 DOI: 10.1111/febs.12245] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 03/05/2013] [Accepted: 03/08/2013] [Indexed: 12/15/2022]
Abstract
A large number of industrially relevant enzymes depend upon nicotinamide cofactors, which are too expensive to be added in stoichiometric amounts. Existing NAD(P)H-recycling systems suffer from low activity, or the generation of side products. H₂-driven cofactor regeneration has the advantage of 100% atom efficiency and the use of H₂ as a cheap reducing agent, in a world where sustainable energy carriers are increasingly attractive. The state of development of H₂-driven cofactor-recycling systems and examples of their integration with enzyme reactions are summarized in this article. The O₂-tolerant NAD⁺-reducing hydrogenase from Ralstonia eutropha is a particularly attractive candidate for this approach, and we therefore discuss its catalytic properties that are relevant for technical applications.
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[NiFe] hydrogenases: a common active site for hydrogen metabolism under diverse conditions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:986-1002. [PMID: 23399489 DOI: 10.1016/j.bbabio.2013.01.015] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 12/06/2012] [Accepted: 01/26/2013] [Indexed: 01/05/2023]
Abstract
Hydrogenase proteins catalyze the reversible conversion of molecular hydrogen to protons and electrons. The most abundant hydrogenases contain a [NiFe] active site; these proteins are generally biased towards hydrogen oxidation activity and are reversibly inhibited by oxygen. However, there are [NiFe] hydrogenase that exhibit unique properties, including aerobic hydrogen oxidation and preferential hydrogen production activity; these proteins are highly relevant in the context of biotechnological devices. This review describes four classes of these "nonstandard" [NiFe] hydrogenases and discusses the electrochemical, spectroscopic, and structural studies that have been used to understand the mechanisms behind this exceptional behavior. A revised classification protocol is suggested in the conclusions, particularly with respect to the term "oxygen-tolerance". This article is part of a special issue entitled: metals in bioenergetics and biomimetics systems.
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Reeve HA, Lauterbach L, Ash PA, Lenz O, Vincent KA. A modular system for regeneration of NAD cofactors using graphite particles modified with hydrogenase and diaphorase moieties. Chem Commun (Camb) 2011; 48:1589-91. [PMID: 21986817 DOI: 10.1039/c1cc14826e] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pyrolytic graphite particles modified with hydrogenase and an NAD(+)/NADH cycling enzyme provide a modular heterogeneous catalyst system for regeneration of oxidised or reduced nicotinamide cofactors using H(2) and H(+) as electron source or sink. Particles can be tuned for cofactor supply under different conditions by appropriate choice of hydrogenase.
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Affiliation(s)
- Holly A Reeve
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
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