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Davis V, Frielingsdorf S, Hu Q, Elsäßer P, Balzer BN, Lenz O, Zebger I, Fischer A. Ultrathin Film Antimony-Doped Tin Oxide Prevents [NiFe] Hydrogenase Inactivation at High Electrode Potentials. ACS APPLIED MATERIALS & INTERFACES 2024; 16:44802-44816. [PMID: 39160667 DOI: 10.1021/acsami.4c08218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/21/2024]
Abstract
For hydrogenases to serve as effective electrocatalysts in hydrogen biotechnological devices, such as enzymatic fuel cells, it is imperative to design electrodes that facilitate stable and functional enzyme immobilization, efficient substrate accessibility, and effective interfacial electron transfer. Recent years have seen considerable advancements in this area, particularly concerning hydrogenases. However, a significant limitation remains: the inactivation of hydrogenases at high oxidative potentials across most developed electrodes. Addressing this issue necessitates a thorough understanding of the interactions between the enzyme and the electrode surface. In this study, we employ ATR-IR spectroscopy combined with electrochemistry in situ to investigate the interaction mechanisms, electrocatalytic behavior, and stability of the oxygen-tolerant membrane-bound [NiFe] hydrogenase from Cupriavidus necator (MBH), which features a His-tag on its small subunit C-terminus. Antimony-doped tin oxide (ATO) thin films were selected as electrodes due to their protein compatibility, suitable potential window, conductivity, and transparency, making them an ideal platform for spectroelectrochemical measurements. Our comprehensive examination of the physiological and electrochemical processes of [NiFe] MBH on ATO thin film electrodes demonstrates that by tuning the electron transport properties of the ATO thin film, we can prevent MBH inactivation at extended oxidative potentials while maintaining direct electron transfer between the enzyme and the electrode.
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Affiliation(s)
- Victoria Davis
- Institute of Inorganic and Analytical Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
- Freiburger Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany
| | - Stefan Frielingsdorf
- Institute of Chemistry, Technische Universität Berlin, Straße des 17. Juni 135 & 124, 10623 Berlin, Germany
| | - Qiwei Hu
- Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
| | - Patrick Elsäßer
- Institute of Inorganic and Analytical Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Bizan N Balzer
- Freiburger Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
| | - Oliver Lenz
- Institute of Chemistry, Technische Universität Berlin, Straße des 17. Juni 135 & 124, 10623 Berlin, Germany
| | - Ingo Zebger
- Institute of Chemistry, Technische Universität Berlin, Straße des 17. Juni 135 & 124, 10623 Berlin, Germany
| | - Anna Fischer
- Institute of Inorganic and Analytical Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
- Freiburger Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
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2
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Fan Q, Waldburger S, Neubauer P, Riedel SL, Gimpel M. Implementation of a high cell density fed-batch for heterologous production of active [NiFe]-hydrogenase in Escherichia coli bioreactor cultivations. Microb Cell Fact 2022; 21:193. [PMID: 36123684 PMCID: PMC9484157 DOI: 10.1186/s12934-022-01919-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/07/2022] [Indexed: 11/13/2022] Open
Abstract
Background O2-tolerant [NiFe]-hydrogenases offer tremendous potential for applications in H2-based technology. As these metalloenzymes undergo a complicated maturation process that requires a dedicated set of multiple accessory proteins, their heterologous production is challenging, thus hindering their fundamental understanding and the development of related applications. Taking these challenges into account, we selected the comparably simple regulatory [NiFe]-hydrogenase (RH) from Cupriavidus necator as a model for the development of bioprocesses for heterologous [NiFe]-hydrogenase production. We already reported recently on the high-yield production of catalytically active RH in Escherichia coli by optimizing the culture conditions in shake flasks. Results In this study, we further increase the RH yield and ensure consistent product quality by a rationally designed high cell density fed-batch cultivation process. Overall, the bioreactor cultivations resulted in ˃130 mg L−1 of catalytically active RH which is a more than 100-fold increase compared to other RH laboratory bioreactor scale processes with C. necator. Furthermore, the process shows high reproducibility of the previously selected optimized conditions and high productivity. Conclusions This work provides a good opportunity to readily supply such difficult-to-express complex metalloproteins economically and at high concentrations to meet the demand in basic and applied studies. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01919-w.
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Affiliation(s)
- Qin Fan
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Saskia Waldburger
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Peter Neubauer
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Sebastian L Riedel
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany
| | - Matthias Gimpel
- Chair of Bioprocess Engineering, Technische Universität Berlin, Ackerstr. 76, ACK24, D-13355, Berlin, Germany.
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Pan H, Wang J, Wu H, Li Z, Lian J. Synthetic biology toolkit for engineering Cupriviadus necator H16 as a platform for CO 2 valorization. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:212. [PMID: 34736496 PMCID: PMC8570001 DOI: 10.1186/s13068-021-02063-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 10/25/2021] [Indexed: 06/09/2023]
Abstract
BACKGROUND CO2 valorization is one of the effective methods to solve current environmental and energy problems, in which microbial electrosynthesis (MES) system has proved feasible and efficient. Cupriviadus necator (Ralstonia eutropha) H16, a model chemolithoautotroph, is a microbe of choice for CO2 conversion, especially with the ability to be employed in MES due to the presence of genes encoding [NiFe]-hydrogenases and all the Calvin-Benson-Basham cycle enzymes. The CO2 valorization strategy will make sense because the required hydrogen can be produced from renewable electricity independently of fossil fuels. MAIN BODY In this review, synthetic biology toolkit for C. necator H16, including genetic engineering vectors, heterologous gene expression elements, platform strain and genome engineering, and transformation strategies, is firstly summarized. Then, the review discusses how to apply these tools to make C. necator H16 an efficient cell factory for converting CO2 to value-added products, with the examples of alcohols, fatty acids, and terpenoids. The review is concluded with the limitation of current genetic tools and perspectives on the development of more efficient and convenient methods as well as the extensive applications of C. necator H16. CONCLUSIONS Great progress has been made on genetic engineering toolkit and synthetic biology applications of C. necator H16. Nevertheless, more efforts are expected in the near future to engineer C. necator H16 as efficient cell factories for the conversion of CO2 to value-added products.
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Affiliation(s)
- Haojie Pan
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jia Wang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Haoliang Wu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zhongjian Li
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jiazhang Lian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
- Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou, 310027, China.
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Lupacchini S, Appel J, Stauder R, Bolay P, Klähn S, Lettau E, Adrian L, Lauterbach L, Bühler B, Schmid A, Toepel J. Rewiring cyanobacterial photosynthesis by the implementation of an oxygen-tolerant hydrogenase. Metab Eng 2021; 68:199-209. [PMID: 34673236 DOI: 10.1016/j.ymben.2021.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/11/2021] [Accepted: 10/16/2021] [Indexed: 10/20/2022]
Abstract
Molecular hydrogen (H2) is considered as an ideal energy carrier to replace fossil fuels in future. Biotechnological H2 production driven by oxygenic photosynthesis appears highly promising, as biocatalyst and H2 syntheses rely mainly on light, water, and CO2 and not on rare metals. This biological process requires coupling of the photosynthetic water oxidizing apparatus to a H2-producing hydrogenase. However, this strategy is impeded by the simultaneous release of oxygen (O2) which is a strong inhibitor of most hydrogenases. Here, we addressed this challenge, by the introduction of an O2-tolerant hydrogenase into phototrophic bacteria, namely the cyanobacterial model strain Synechocystis sp. PCC 6803. To this end, the gene cluster encoding the soluble, O2-tolerant, and NAD(H)-dependent hydrogenase from Ralstonia eutropha (ReSH) was functionally transferred to a Synechocystis strain featuring a knockout of the native O2 sensitive hydrogenase. Intriguingly, photosynthetically active cells produced the O2 tolerant ReSH, and activity was confirmed in vitro and in vivo. Further, ReSH enabled the constructed strain Syn_ReSH+ to utilize H2 as sole electron source to fix CO2. Syn_ReSH+ also was able to produce H2 under dark fermentative conditions as well as in presence of light, under conditions fostering intracellular NADH excess. These findings highlight a high level of interconnection between ReSH and cyanobacterial redox metabolism. This study lays a foundation for further engineering, e.g., of electron transfer to ReSH via NADPH or ferredoxin, to finally enable photosynthesis-driven H2 production.
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Affiliation(s)
- Sara Lupacchini
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Jens Appel
- Department of Biology, Botanical Institute, University Kiel, 24118, Kiel, Germany
| | - Ron Stauder
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Paul Bolay
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Stephan Klähn
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Elisabeth Lettau
- Institute for Chemistry, Technische Universität Berlin, 10623, Berlin, Germany
| | - Lorenz Adrian
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany; Chair of Geobiotechnology, Technische Universität Berlin, 10923, Berlin, Germany
| | - Lars Lauterbach
- Institute for Chemistry, Technische Universität Berlin, 10623, Berlin, Germany; Institute of Applied Microbiology, Rheinisch-Westfälische Technische Hochschule Aachen, 52074, Aachen, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Andreas Schmid
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany
| | - Jörg Toepel
- Department of Solar Materials, Helmholtz Centre for Environmental Research -UFZ, 04318, Leipzig, Germany.
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Lorent C, Pelmenschikov V, Frielingsdorf S, Schoknecht J, Caserta G, Yoda Y, Wang H, Tamasaku K, Lenz O, Cramer SP, Horch M, Lauterbach L, Zebger I. Exploring Structure and Function of Redox Intermediates in [NiFe]-Hydrogenases by an Advanced Experimental Approach for Solvated, Lyophilized and Crystallized Metalloenzymes. Angew Chem Int Ed Engl 2021; 60:15854-15862. [PMID: 33783938 PMCID: PMC8360142 DOI: 10.1002/anie.202100451] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/20/2021] [Indexed: 01/28/2023]
Abstract
To study metalloenzymes in detail, we developed a new experimental setup allowing the controlled preparation of catalytic intermediates for characterization by various spectroscopic techniques. The in situ monitoring of redox transitions by infrared spectroscopy in enzyme lyophilizate, crystals, and solution during gas exchange in a wide temperature range can be accomplished as well. Two O2 -tolerant [NiFe]-hydrogenases were investigated as model systems. First, we utilized our platform to prepare highly concentrated hydrogenase lyophilizate in a paramagnetic state harboring a bridging hydride. This procedure proved beneficial for 57 Fe nuclear resonance vibrational spectroscopy and revealed, in combination with density functional theory calculations, the vibrational fingerprint of this catalytic intermediate. The same in situ IR setup, combined with resonance Raman spectroscopy, provided detailed insights into the redox chemistry of enzyme crystals, underlining the general necessity to complement X-ray crystallographic data with spectroscopic analyses.
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Affiliation(s)
- Christian Lorent
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Vladimir Pelmenschikov
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Stefan Frielingsdorf
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Janna Schoknecht
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Giorgio Caserta
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Yoshitaka Yoda
- Japan Synchrotron Radiation Research InstituteSPring-81-1-1 Kouto, Mikazuki-choSayo-gunHyogo679-5198Japan
| | - Hongxin Wang
- SETI Institute189 Bernardo AvenueMountain ViewCalifornia94043USA
| | - Kenji Tamasaku
- RIKEN SPring-8 center1-1-1 Kouto, Sayo-choSayo-gunHyogo679-5148Japan
| | - Oliver Lenz
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | | | - Marius Horch
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
- Department of PhysicsFreie Universität BerlinArnimallee 1414195BerlinGermany
| | - Lars Lauterbach
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Ingo Zebger
- Department of ChemistryTechnische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
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6
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Lorent C, Pelmenschikov V, Frielingsdorf S, Schoknecht J, Caserta G, Yoda Y, Wang H, Tamasaku K, Lenz O, Cramer SP, Horch M, Lauterbach L, Zebger I. Ein neuer Aufbau zur Untersuchung der Struktur und Funktion von solvatisierten, lyophilisierten und kristallinen Metalloenzymen – veranschaulicht anhand von [NiFe]‐Hydrogenasen. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202100451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Christian Lorent
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Vladimir Pelmenschikov
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Stefan Frielingsdorf
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Janna Schoknecht
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Giorgio Caserta
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Yoshitaka Yoda
- Japan Synchrotron Radiation Research Institute SPring-8 1-1-1 Kouto, Mikazuki-cho Sayo-gun Hyogo 679-5198 Japan
| | - Hongxin Wang
- SETI Institute 189 Bernardo Avenue Mountain View California 94043 USA
| | - Kenji Tamasaku
- RIKEN SPring-8 center 1-1-1 Kouto, Sayo-cho Sayo-gun Hyogo 679-5148 Japan
| | - Oliver Lenz
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Stephen P. Cramer
- SETI Institute 189 Bernardo Avenue Mountain View California 94043 USA
| | - Marius Horch
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
- Department of Physics Freie Universität Berlin Arnimallee 14 14195 Berlin Deutschland
| | - Lars Lauterbach
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
| | - Ingo Zebger
- Department of Chemistry Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Deutschland
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Inactivation of the uptake hydrogenase in the purple non-sulfur photosynthetic bacterium Rubrivivax gelatinosus CBS enables a biological water–gas shift platform for H2 production. ACTA ACUST UNITED AC 2019; 46:993-1002. [DOI: 10.1007/s10295-019-02173-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 04/03/2019] [Indexed: 10/27/2022]
Abstract
Abstract
Biological H2 production has potential to address energy security and environmental concerns if produced from renewable or waste sources. The purple non-sulfur photosynthetic bacterium Rubrivivax gelatinosus CBS produces H2 while oxidizing CO, a component of synthesis gas (Syngas). CO-linked H2 production is facilitated by an energy-converting hydrogenase (Ech), while a subsequent H2 oxidation reaction is catalyzed by a membrane-bound hydrogenase (MBH). Both hydrogenases contain [NiFe] active sites requiring 6 maturation factors (HypA-F) for assembly, but it is unclear which of the two annotated sets of hyp genes are required for each in R. gelatinosus CBS. Herein, we report correlated expression of hyp1 genes with Ech genes and hyp2 expression with MBH genes. Moreover, we find that while Ech H2 evolving activity is only delayed when hyp1 is deleted, hyp2 deletion completely disrupts MBH H2 uptake, providing a platform for a biologically driven water–gas shift reaction to produce H2 from CO.
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8
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Hartmann S, Frielingsdorf S, Ciaccafava A, Lorent C, Fritsch J, Siebert E, Priebe J, Haumann M, Zebger I, Lenz O. O2-Tolerant H2 Activation by an Isolated Large Subunit of a [NiFe] Hydrogenase. Biochemistry 2018; 57:5339-5349. [DOI: 10.1021/acs.biochem.8b00760] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sven Hartmann
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Stefan Frielingsdorf
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Alexandre Ciaccafava
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Christian Lorent
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Johannes Fritsch
- Department of Biology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Elisabeth Siebert
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Jacqueline Priebe
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Michael Haumann
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Ingo Zebger
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
| | - Oliver Lenz
- Department of Chemistry, Sekr. PC14, Technische Universität Berlin, 10623 Berlin, Germany
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9
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Raberg M, Volodina E, Lin K, Steinbüchel A. Ralstonia eutrophaH16 in progress: Applications beside PHAs and establishment as production platform by advanced genetic tools. Crit Rev Biotechnol 2017; 38:494-510. [DOI: 10.1080/07388551.2017.1369933] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Matthias Raberg
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Elena Volodina
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Kaichien Lin
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Alexander Steinbüchel
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Münster, Germany
- Environmental Science Department, King Abdulaziz University, Jeddah, Saudi Arabia
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10
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El-Khouly ME, El-Mohsnawy E, Fukuzumi S. Solar energy conversion: From natural to artificial photosynthesis. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2017. [DOI: 10.1016/j.jphotochemrev.2017.02.001] [Citation(s) in RCA: 182] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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11
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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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12
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Harris BJ, Cheng X, Frymier P. Structure and Function of Photosystem I–[FeFe] Hydrogenase Protein Fusions: An All-Atom Molecular Dynamics Study. J Phys Chem B 2016; 120:599-609. [DOI: 10.1021/acs.jpcb.5b07812] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bradley J. Harris
- College
of Engineering and Computer Science, University of Tennessee, Chattanooga, Tennessee 37403, United States
| | - Xiaolin Cheng
- Center for
Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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13
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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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Development of a plasmid addicted system that is independent of co-inducers, antibiotics and specific carbon source additions for bioproduct (1-butanol) synthesis in Escherichia coli. Metab Eng Commun 2014; 2:6-12. [PMID: 34150503 PMCID: PMC8193244 DOI: 10.1016/j.meteno.2014.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 11/24/2014] [Accepted: 12/02/2014] [Indexed: 10/29/2022] Open
Abstract
Synthetic biology approaches for the synthesis of value-based products provide interesting and potentially fruitful possibilities for generating a wide variety of useful compounds and biofuels. However, industrial production is hampered by the costs associated with the need to supplement large microbial cultures with expensive but necessary co-inducer compounds and antibiotics that are required for up-regulating synthetic gene expression and maintaining plasmid-borne synthetic genes, respectively. To address these issues, a metabolism-based plasmid addiction system, which relies on lipopolysaccharide biosynthesis and maintenance of cellular redox balance for 1-butanol production; and utilizes an active constitutive promoter, was developed in Escherichia coli. Expression of the plasmid is absolutely required for cell viability and 1-butanol production. This system abrogates the need for expensive antibiotics and co-inducer molecules so that plasmid-borne synthetic genes may be expressed at high levels in a cost-effective manner. To illustrate these principles, high level and sustained production of 1-butanol by E. coli was demonstrated under different growth conditions and in semi-continuous batch cultures, in the absence of antibiotics and co-inducer molecules.
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15
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Harris BJ, Cheng X, Frymier P. All-atom molecular dynamics simulation of a photosystem i/detergent complex. J Phys Chem B 2014; 118:11633-45. [PMID: 25233289 DOI: 10.1021/jp507157e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
All-atom molecular dynamics (MD) simulation was used to investigate the solution structure and dynamics of the photosynthetic pigment-protein complex photosystem I (PSI) from Thermosynechococcus elongatus embedded in a toroidal belt of n-dodecyl-β-d-maltoside (DDM) detergent. Evaluation of root-mean-square deviations (RMSDs) relative to the known crystal structure show that the protein complex surrounded by DDM molecules is stable during the 200 ns simulation time, and root-mean-square fluctuation (RMSF) analysis indicates that regions of high local mobility correspond to solvent-exposed regions such as turns in the transmembrane α-helices and flexible loops on the stromal and lumenal faces. Comparing the protein-detergent complex to a pure detergent micelle, the detergent surrounding the PSI trimer is found to be less densely packed but with more ordered detergent tails, contrary to what is seen in most lipid bilayer models. We also investigated any functional implications for the observed conformational dynamics and protein-detergent interactions, discovering interesting structural changes in the psaL subunits associated with maintaining the trimeric structure of the protein. Importantly, we find that the docking of soluble electron mediators such as cytochrome c6 and ferredoxin to PSI is not significantly impacted by the solubilization of PSI in detergent.
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Affiliation(s)
- Bradley J Harris
- Department of Chemical and Biomolecular Engineering, ‡Department of Biochemistry and Cellular and Molecular Biology, §Sustainable Energy Education and Research Center, and ∥Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee , Knoxville, Tennessee 37996, United States
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16
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Development of a transferable bimolecular fluorescence complementation system for the investigation of interactions between poly(3-hydroxybutyrate) granule-associated proteins in Gram-negative bacteria. Appl Environ Microbiol 2013; 79:2989-99. [PMID: 23435892 DOI: 10.1128/aem.03965-12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Poly(3-hydroxybutyrate) (PHB) granules are organelle-like multienzyme-polymer complexes (carbonosomes) and are widespread storage compounds in prokaryotes. The interaction of three PHB granule-bound proteins (PHB synthase PhaC1, phasin PhaP5, and PHB/DNA binding protein PhaM) was studied in vivo by bimolecular fluorescence complementation (BiFC) microscopy in Ralstonia eutropha. To this end, a mobilizable 2-plasmid system for arabinose-controlled expression of protein fusions with the N-terminal (YN) and C-terminal (YC) parts of the enhanced yellow fluorescent protein (eYfp) in Gram-negative bacteria was developed. Both plasmids were stably expressed in Escherichia coli and in transconjugants of R. eutropha. Homo-oligomerization of PhaC1, PhaP5, and PhaM and interactions between PhaC1 and PhaM and between PhaM and PhaP5 were detected in R. eutropha and colocalized with PHB granules under PHB-permissive conditions. PhaM-PhaC1 complexes were detected near the midcell/nucleoid region in the absence of PHB. Expression of BiFC complexes in R. eutropha with PhaM (PhaM homo-oligomers or PhaM-PhaC1 or PhaM-PhaP5 complexes) resulted in substantial cell elongation compared to wild-type cells and in BiFC signals that were generally located near the midcell/nucleoid region. Western blot analysis of wild-type cell extracts and proteome analysis of PHB granule-bound proteins revealed that PhaM and PhaP5 are expressed in R. eutropha and that PhaM is constitutively expressed independently of the presence or absence of PHB. Size exclusion chromatography analysis in combination with cross-linking experiments of purified PhaP5-His6 and PhaM-His6 showed that PhaP5 forms dimers and that PhaM is present in oligomeric (dodecamer) form. Implications of this finding for subcellular PHB localization and initiation of PHB granule formation in R. eutropha will be discussed.
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17
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Jugder BE, Welch J, Aguey-Zinsou KF, Marquis CP. Fundamentals and electrochemical applications of [Ni–Fe]-uptake hydrogenases. RSC Adv 2013. [DOI: 10.1039/c3ra22668a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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18
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Kargul J, Janna Olmos JD, Krupnik T. Structure and function of photosystem I and its application in biomimetic solar-to-fuel systems. JOURNAL OF PLANT PHYSIOLOGY 2012; 169:1639-1653. [PMID: 22784471 DOI: 10.1016/j.jplph.2012.05.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 05/09/2012] [Accepted: 05/11/2012] [Indexed: 06/01/2023]
Abstract
Photosystem I (PSI) is one of the most efficient biological macromolecular complexes that converts solar energy into condensed energy of chemical bonds. Despite high structural complexity, PSI operates with a quantum yield close to 1.0 and to date, no man-made synthetic system approached this remarkable efficiency. This review highlights recent developments in dissecting molecular structure and function of the prokaryotic and eukaryotic PSI. It also overviews progress in the application of this complex as a natural photocathode for production of hydrogen within the biomimetic solar-to-fuel nanodevices.
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Affiliation(s)
- Joanna Kargul
- Department of Plant Molecular Physiology, University of Warsaw, ul. Miecznikowa 1, 02-096 Warsaw, Poland.
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19
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Bürstel I, Siebert E, Winter G, Hummel P, Zebger I, Friedrich B, Lenz O. A universal scaffold for synthesis of the Fe(CN)2(CO) moiety of [NiFe] hydrogenase. J Biol Chem 2012; 287:38845-53. [PMID: 23019332 DOI: 10.1074/jbc.m112.376947] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hydrogen-cycling [NiFe] hydrogenases harbor a dinuclear catalytic center composed of nickel and iron ions, which are coordinated by four cysteine residues. Three unusual diatomic ligands in the form of two cyanides (CN(-)) and one carbon monoxide (CO) are bound to the iron and apparently account for the complexity of the cofactor assembly process, which involves the function of at least six auxiliary proteins, designated HypA, -B, -C, -D, -E, and -F. It has been demonstrated previously that the HypC, -D, -E, and -F proteins participate in cyanide synthesis and transfer. Here, we show by infrared spectroscopic analysis that the purified HypCD complexes from Ralstonia eutropha and Escherichia coli carry in addition to both cyanides the CO ligand. We present experimental evidence that in vivo the attachment of the CN(-) ligands is a prerequisite for subsequent CO binding. With the aid of genetic engineering and subsequent mutant analysis, the functional role of conserved cysteine residues in HypD from R. eutropha was investigated. Our results demonstrate that the HypCD complex serves as a scaffold for the assembly of the Fe(CN)(2)(CO) entity of [NiFe] hydrogenase.
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Affiliation(s)
- Ingmar Bürstel
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, Chausseestrasse 117,10115 Berlin, Germany
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Wang B, Wang J, Zhang W, Meldrum DR. Application of synthetic biology in cyanobacteria and algae. Front Microbiol 2012; 3:344. [PMID: 23049529 PMCID: PMC3446811 DOI: 10.3389/fmicb.2012.00344] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 09/05/2012] [Indexed: 11/16/2022] Open
Abstract
Cyanobacteria and algae are becoming increasingly attractive cell factories for producing renewable biofuels and chemicals due to their ability to capture solar energy and CO2 and their relatively simple genetic background for genetic manipulation. Increasing research efforts from the synthetic biology approach have been made in recent years to modify cyanobacteria and algae for various biotechnological applications. In this article, we critically review recent progresses in developing genetic tools for characterizing or manipulating cyanobacteria and algae, the applications of genetically modified strains for synthesizing renewable products such as biofuels and chemicals. In addition, the emergent challenges in the development and application of synthetic biology for cyanobacteria and algae are also discussed.
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Affiliation(s)
- Bo Wang
- Center for Biosignatures Discovery Automation, The Biodesign Institute, Arizona State University Tempe, AZ, USA ; Biological Design Graduate Program, Arizona State University Tempe, AZ, USA
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21
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Autotrophic production of stable-isotope-labeled arginine in Ralstonia eutropha strain H16. Appl Environ Microbiol 2012; 78:7884-90. [PMID: 22941075 DOI: 10.1128/aem.01972-12] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
With the aim of improving industrial-scale production of stable-isotope (SI)-labeled arginine, we have developed a system for the heterologous production of the arginine-containing polymer cyanophycin in recombinant strains of Ralstonia eutropha under lithoautotrophic growth conditions. We constructed an expression plasmid based on the cyanophycin synthetase gene (cphA) of Synechocystis sp. strain PCC6308 under the control of the strong P(cbbL) promoter of the R. eutropha H16 cbb(c) operon (coding for autotrophic CO(2) fixation). In batch cultures growing on H(2) and CO(2) as sole sources of energy and carbon, respectively, the cyanophycin content of cells reached 5.5% of cell dry weight (CDW). However, in the absence of selection (i.e., in antibiotic-free medium), plasmid loss led to a substantial reduction in yield. We therefore designed a novel addiction system suitable for use under lithoautotrophic conditions. Based on the hydrogenase transcription factor HoxA, this system mediated stabilized expression of cphA during lithoautotrophic cultivation without the need for antibiotics. The maximum yield of cyanophycin was 7.1% of CDW. To test the labeling efficiency of our expression system under actual production conditions, cells were grown in 10-liter-scale fermentations fed with (13)CO(2) and (15)NH(4)Cl, and the (13)C/(15)N-labeled cyanophycin was subsequently extracted by treatment with 0.1 M HCl; 2.5 to 5 g of [(13)C/(15)N]arginine was obtained per fed-batch fermentation, corresponding to isotope enrichments of 98.8% to 99.4%.
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Nikandrov VV, Borisova YV, Bocharov EA, Usachev MA, Nizova GV, Nadtochenko VA, Lukashev EP, Trubitsin BV, Tikhonov AN, Kurashov VN, Mamedov MD, Semenov AY. Photochemical properties of photosystem 1 immobilized in a mesoporous semiconductor matrix. HIGH ENERGY CHEMISTRY 2012. [DOI: 10.1134/s0018143912030095] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Artero V, Fontecave M. Light-driven bioinspired water splitting: Recent developments in photoelectrode materials. CR CHIM 2011. [DOI: 10.1016/j.crci.2011.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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24
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Abstract
Plants are light-driven "green" factories able to synthesize more than 200,000 different bioactive natural products, many of which are high-value products used as drugs (e.g., artemisinin, taxol, and thapsigargin). In the formation of natural products, cytochrome P450 (P450) monooxygenases play a key role in catalyzing regio- and stereospecific hydroxylations that are often difficult to achieve using the approaches of chemical synthesis. P450-catalyzed monooxygenations are dependent on electron donation typically from NADPH catalyzed by NADPH-cytochrome P450 oxidoreductase (CPR). The consumption of the costly cofactor NADPH constitutes an economical obstacle for biotechnological in vitro applications of P450s. This bottleneck has been overcome by the design of an in vitro system able to carry out light-driven P450 hydroxylations using photosystem I (PSI) for light harvesting and generation of reducing equivalents necessary to drive the P450 catalytic cycle. The in vitro system is based on the use of isolated PSI and P450 membrane complexes using ferredoxin as an electron carrier. The turnover rate of the P450 in the light-driven system was 413 min(-1) compared to 228 min(-1) in the native CPR-catalyzed system. The use of light as a substitute for costly NADPH offers a new avenue for P450-mediated synthesis of complex bioactive natural products using in vitro synthetic biology approaches.
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Affiliation(s)
- Kenneth Jensen
- Department
of Plant Biology and Biotechnology, ‡VKR Research Centre “Pro-Active Plants”, and §Center for Synthetic
Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Poul Erik Jensen
- Department
of Plant Biology and Biotechnology, ‡VKR Research Centre “Pro-Active Plants”, and §Center for Synthetic
Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Birger Lindberg Møller
- Department
of Plant Biology and Biotechnology, ‡VKR Research Centre “Pro-Active Plants”, and §Center for Synthetic
Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
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Friedrich B, Fritsch J, Lenz O. Oxygen-tolerant hydrogenases in hydrogen-based technologies. Curr Opin Biotechnol 2011; 22:358-64. [DOI: 10.1016/j.copbio.2011.01.006] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 01/20/2011] [Accepted: 01/21/2011] [Indexed: 12/30/2022]
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The maturation factors HoxR and HoxT contribute to oxygen tolerance of membrane-bound [NiFe] hydrogenase in Ralstonia eutropha H16. J Bacteriol 2011; 193:2487-97. [PMID: 21441514 DOI: 10.1128/jb.01427-10] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The membrane-bound [NiFe] hydrogenase (MBH) of Ralstonia eutropha H16 undergoes a complex maturation process comprising cofactor assembly and incorporation, subunit oligomerization, and finally twin-arginine-dependent membrane translocation. Due to its outstanding O(2) and CO tolerance, the MBH is of biotechnological interest and serves as a molecular model for a robust hydrogen catalyst. Adaptation of the enzyme to oxygen exposure has to take into account not only the catalytic reaction but also biosynthesis of the intricate redox cofactors. Here, we report on the role of the MBH-specific accessory proteins HoxR and HoxT, which are key components in MBH maturation at ambient O(2) levels. MBH-driven growth on H(2) is inhibited or retarded at high O(2) partial pressure (pO(2)) in mutants inactivated in the hoxR and hoxT genes. The ratio of mature and nonmature forms of the MBH small subunit is shifted toward the precursor form in extracts derived from the mutant cells grown at high pO(2). Lack of hoxR and hoxT can phenotypically be restored by providing O(2)-limited growth conditions. Analysis of copurified maturation intermediates leads to the conclusion that the HoxR protein is a constituent of a large transient protein complex, whereas the HoxT protein appears to function at a final stage of MBH maturation. UV-visible spectroscopy of heterodimeric MBH purified from hoxR mutant cells points to alterations of the Fe-S cluster composition. Thus, HoxR may play a role in establishing a specific Fe-S cluster profile, whereas the HoxT protein seems to be beneficial for cofactor stability under aerobic conditions.
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Lauterbach L, Liu J, Horch M, Hummel P, Schwarze A, Haumann M, Vincent KA, Lenz O, Zebger I. The Hydrogenase Subcomplex of the NAD+-Reducing [NiFe] Hydrogenase from Ralstonia eutropha - Insights into Catalysis and Redox Interconversions. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201001053] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Reisner E. Solar Hydrogen Evolution with Hydrogenases: From Natural to Hybrid Systems. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.201000986] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Erwin Reisner
- School of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
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