1
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Britt RD, Rauchfuss TB, Rao G. The H-cluster of [FeFe] Hydrogenases: Its Enzymatic Synthesis and Parallel Inorganic Semisynthesis. Acc Chem Res 2024; 57:1941-1950. [PMID: 38937148 PMCID: PMC11256358 DOI: 10.1021/acs.accounts.4c00231] [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: 04/22/2024] [Revised: 06/12/2024] [Accepted: 06/14/2024] [Indexed: 06/29/2024]
Abstract
ConspectusNature's prototypical hydrogen-forming catalysts─hydrogenases─have attracted much attention because they catalyze hydrogen evolution at near zero overpotential and ambient conditions. Beyond any possible applications in the energy sphere, the hydrogenases feature complicated active sites, which implies novel biosynthetic pathways. In terms of the variety of cofactors, the [FeFe]-hydrogenase is among the most complex.For more than a decade, we have worked on the biosynthesis of the active site of [FeFe] hydrogenases. This site, the H-cluster, is a six-iron ensemble consisting of a [4Fe-4S]H cluster linked to a [2Fe]H cluster that is coordinated to CO, cyanide, and a unique organic azadithiolate ligand. Many years ago, three enzymes, namely, HydG, HydE, and HydF, were shown to be required for the biosynthesis and the in vitro maturation of [FeFe] hydrogenases. The structures of the maturases were determined crystallographically, but still little progress was made on the biosynthetic pathway. As described in this Account, the elucidation of the biosynthetic pathway began in earnest with the identification of a molecular iron-cysteinate complex produced within HydG.In this Account, we present our most recent progress toward the molecular mechanism of [2Fe]H biosynthesis using a collaborative approach involving cell-free biosynthesis, isotope and element-sensitive spectroscopies, as well as inorganic synthesis of purported biosynthetic intermediates. Our study starts from the radical SAM enzyme HydG that lyses tyrosine into CO and cyanide and forms an Fe(CO)2(CN)-containing species. Crystallographic identification of a unique auxiliary 5Fe-4S cluster in HydG leads to a proposed catalytic cycle in which a free cysteine-chelated "dangler" Fe serves as the platform for the stepwise formation of a [4Fe-4S][Fe(CO)(CN)(cysteinate)] intermediate, which releases the [Fe(CO)2(CN)(cysteinate)] product, Complex B. Since Complex B is unstable, we applied synthetic organometallic chemistry to make an analogue, syn-B, and showed that it fully replaces HydG in the in vitro maturation of the H-cluster. Syn-B serves as the substrate for the next radical SAM enzyme HydE, where the low-spin Fe(II) center is activated by 5'-dAdo• to form an adenosylated Fe(I) intermediate. We propose that this Fe(I) species strips the carbon backbone and dimerizes in HydE to form a [Fe2(SH)2(CO)4(CN)2]2- product. This mechanistic scenario is supported by the use of a synthetic version of this dimer complex, syn-dimer, which allows for the formation of active hydrogenase with only the HydF maturase. Further application of this semisynthesis strategy shows that an [Fe2(SCH2NH2)2(CO)4(CN)2]2- complex can activate the apo hydrogenase, marking it as the last biosynthetic intermediate en route to the H-cluster. This combined enzymatic and semisynthetic approach greatly accelerates our understanding of H-cluster biosynthesis. We anticipate additional mechanistic details regarding H-cluster biosynthesis to be gleaned, and this methodology may be further applied in the study of other complex metallocofactors.
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Affiliation(s)
- R. David Britt
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United
States
| | - Thomas B. Rauchfuss
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, Urbana, Illinois 61820, United States
| | - Guodong Rao
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United
States
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2
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Brabender M, Henriques Pereira DP, Mrnjavac N, Schlikker ML, Kimura ZI, Sucharitakul J, Kleinermanns K, Tüysüz H, Buckel W, Preiner M, Martin WF. Ferredoxin reduction by hydrogen with iron functions as an evolutionary precursor of flavin-based electron bifurcation. Proc Natl Acad Sci U S A 2024; 121:e2318969121. [PMID: 38513105 PMCID: PMC7615787 DOI: 10.1073/pnas.2318969121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 02/14/2024] [Indexed: 03/23/2024] Open
Abstract
Autotrophic theories for the origin of metabolism posit that the first cells satisfied their carbon needs from CO2 and were chemolithoautotrophs that obtained their energy and electrons from H2. The acetyl-CoA pathway of CO2 fixation is central to that view because of its antiquity: Among known CO2 fixing pathways it is the only one that is i) exergonic, ii) occurs in both bacteria and archaea, and iii) can be functionally replaced in full by single transition metal catalysts in vitro. In order to operate in cells at a pH close to 7, however, the acetyl-CoA pathway requires complex multi-enzyme systems capable of flavin-based electron bifurcation that reduce low potential ferredoxin-the physiological donor of electrons in the acetyl-CoA pathway-with electrons from H2. How can the acetyl-CoA pathway be primordial if it requires flavin-based electron bifurcation? Here, we show that native iron (Fe0), but not Ni0, Co0, Mo0, NiFe, Ni2Fe, Ni3Fe, or Fe3O4, promotes the H2-dependent reduction of aqueous Clostridium pasteurianum ferredoxin at pH 8.5 or higher within a few hours at 40 °C, providing the physiological function of flavin-based electron bifurcation, but without the help of enzymes or organic redox cofactors. H2-dependent ferredoxin reduction by iron ties primordial ferredoxin reduction and early metabolic evolution to a chemical process in the Earth's crust promoted by solid-state iron, a metal that is still deposited in serpentinizing hydrothermal vents today.
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Affiliation(s)
- Max Brabender
- Institute of Molecular Evolution, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf40225, Germany
| | - Delfina P. Henriques Pereira
- Microcosm Earth Center, Research Group for Geochemical Protozymes, Max Planck Institute for Terrestrial Microbiology and Philipps University, Marburg35032, Germany
| | - Natalia Mrnjavac
- Institute of Molecular Evolution, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf40225, Germany
| | - Manon Laura Schlikker
- Institute of Molecular Evolution, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf40225, Germany
| | - Zen-Ichiro Kimura
- Institute of Molecular Evolution, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf40225, Germany
- Department of Civil and Environmental Engineering, National Institute of Technology, Kure College, Kure, Hiroshima737-8506, Japan
| | - Jeerus Sucharitakul
- Department of Biochemistry, Chulalongkorn University, Patumwan, Bangkok10330, Thailand
| | - Karl Kleinermanns
- Institute for Physical Chemistry, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf40225, Germany
| | - Harun Tüysüz
- Max Planck Institute for Coal Research, Department of Heterogeneous Catalysis, Mülheim an der Ruhr45470, Germany
| | - Wolfgang Buckel
- Max Planck Institute for Terrestrial Microbiology, Marburg35043, Germany
- Laboratory for Microbiology, Department of Biology, Philipps University, Marburg35043, Germany
- Center for Synthetic Microbiology SYNMIKRO, Philipps University, Marburg35043, Germany
| | - Martina Preiner
- Microcosm Earth Center, Research Group for Geochemical Protozymes, Max Planck Institute for Terrestrial Microbiology and Philipps University, Marburg35032, Germany
| | - William F. Martin
- Institute of Molecular Evolution, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf40225, Germany
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3
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Balci B, O'Neill RD, Shepard EM, Pagnier A, Marlott A, Mock MT, Broderick WE, Broderick JB. Semisynthetic maturation of [FeFe]-hydrogenase using [Fe 2(μ-SH) 2(CN) 2(CO) 4] 2-: key roles for HydF and GTP. Chem Commun (Camb) 2023. [PMID: 37376915 DOI: 10.1039/d3cc02169f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
Here we describe maturation of the [FeFe]-hydrogenase from its [4Fe-4S]-bound precursor state by using the synthetic complex [Fe2(μ-SH)2(CN)2(CO)4]2- together with HydF and components of the glycine cleavage system, but in the absence of the maturases HydE and HydG. This semisynthetic and fully-defined maturation provides new insights into the nature of H-cluster biosynthesis.
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Affiliation(s)
- Batuhan Balci
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Roark D O'Neill
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Eric M Shepard
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Adrien Pagnier
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Alexander Marlott
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Michael T Mock
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - William E Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Joan B Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
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4
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Pagnier A, Balci B, Shepard EM, Yang H, Warui DM, Impano S, Booker SJ, Hoffman BM, Broderick WE, Broderick JB. [FeFe]-Hydrogenase: Defined Lysate-Free Maturation Reveals a Key Role for Lipoyl-H-Protein in DTMA Ligand Biosynthesis. Angew Chem Int Ed Engl 2022; 61:e202203413. [PMID: 35319808 PMCID: PMC9117470 DOI: 10.1002/anie.202203413] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Indexed: 11/09/2022]
Abstract
Maturation of [FeFe]-hydrogenase (HydA) involves synthesis of a CO, CN- , and dithiomethylamine (DTMA)-coordinated 2Fe subcluster that is inserted into HydA to make the active hydrogenase. This process requires three maturation enzymes: the radical S-adenosyl-l-methionine (SAM) enzymes HydE and HydG, and the GTPase HydF. In vitro maturation with purified maturation enzymes has been possible only when clarified cell lysate was added, with the lysate presumably providing essential components for DTMA synthesis and delivery. Here we report maturation of [FeFe]-hydrogenase using a fully defined system that includes components of the glycine cleavage system (GCS), but no cell lysate. Our results reveal for the first time an essential role for the aminomethyl-lipoyl-H-protein of the GCS in hydrogenase maturation and the synthesis of the DTMA ligand of the H-cluster. In addition, we show that ammonia is the source of the bridgehead nitrogen of DTMA.
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Affiliation(s)
- Adrien Pagnier
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Batuhan Balci
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Eric M Shepard
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Hao Yang
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Douglas M Warui
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - Stella Impano
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Squire J Booker
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - William E Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Joan B Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA
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5
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Pagnier A, Balci B, Shepard EM, Yang H, Warui DM, Impano S, Booker SJ, Hoffman BM, Broderick WE, Broderick JB. [FeFe]‐Hydrogenase: Defined Lysate‐Free Maturation Reveals a Key Role for Lipoyl‐H‐Protein in DTMA Ligand Biosynthesis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Adrien Pagnier
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Batuhan Balci
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Eric M. Shepard
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Hao Yang
- Department of Chemistry Northwestern University Evanston IL 60208 USA
| | - Douglas M. Warui
- Department of Chemistry The Pennsylvania State University University Park PA 16802 USA
| | - Stella Impano
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Squire J. Booker
- Department of Chemistry The Pennsylvania State University University Park PA 16802 USA
- Howard Hughes Medical Institute Chevy Chase MD 20815 USA
| | - Brian M. Hoffman
- Department of Chemistry Northwestern University Evanston IL 60208 USA
| | - William E. Broderick
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Joan B. Broderick
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
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6
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Britt RD, Tao L, Rao G, Chen N, Wang LP. Proposed Mechanism for the Biosynthesis of the [FeFe] Hydrogenase H-Cluster: Central Roles for the Radical SAM Enzymes HydG and HydE. ACS BIO & MED CHEM AU 2022; 2:11-21. [PMID: 35187536 PMCID: PMC8855341 DOI: 10.1021/acsbiomedchemau.1c00035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/08/2021] [Accepted: 10/11/2021] [Indexed: 01/05/2023]
Abstract
Radical S-adenosylmethionine (radical SAM or rSAM) enzymes use their S-adenosylmethionine cofactor bound to a unique Fe of a [4Fe-4S] cluster to generate the "hot" 5'-deoxyadenosyl radical, which drives highly selective radical reactions via specific interactions with a given rSAM enzyme's substrate. This Perspective focuses on the two rSAM enzymes involved in the biosynthesis of the organometallic H-cluster of [FeFe] hydrogenases. We present here a detailed sequential model initiated by HydG, which lyses a tyrosine substrate via a 5'-deoxyadenosyl H atom abstraction from those amino acid's amino group, initially producing dehydroglycine and an oxidobenzyl radical. In this model, two successive radical cascade reactions lead ultimately to the formation of HydG's product, a mononuclear Fe organometallic complex: [Fe(II)(CN)(CO)2(cysteinate)]-, with the iron originating from a unique "dangler" Fe coordinated by a cysteine ligand providing a sulfur bridge to another [4Fe-4S] auxiliary cluster in the enzyme. In turn, in this model, [Fe(II)(CN)(CO)2(cysteinate)]- is the substrate for HydE, the second rSAM enzyme in the biosynthetic pathway, which activates this mononuclear organometallic unit for dimerization, forming a [Fe2S2(CO)4(CN)2] precursor to the [2Fe] H component of the H-cluster, requiring only the completion of the bridging azadithiolate (SCH2NHCH2S) ligand. This model is built upon a foundation of data that incorporates cell-free synthesis, isotope sensitive spectroscopies, and the selective use of synthetic complexes substituting for intermediates in the enzymatic "assembly line". We discuss controversies pertaining to this model and some remaining open issues to be addressed by future work.
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Affiliation(s)
- R David Britt
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Lizhi Tao
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Guodong Rao
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Nanhao Chen
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Lee-Ping Wang
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
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7
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Rao G, Chen N, Marchiori DA, Wang LP, Britt RD. Accumulation and Pulse Electron Paramagnetic Resonance Spectroscopic Investigation of the 4-Oxidobenzyl Radical Generated in the Radical S-Adenosyl-l-methionine Enzyme HydG. Biochemistry 2022; 61:107-116. [PMID: 34989236 DOI: 10.1021/acs.biochem.1c00619] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The radical S-adenosyl-l-methionine (SAM) enzyme HydG cleaves tyrosine to generate CO and CN- ligands of the [FeFe] hydrogenase H-cluster, accompanied by the formation of a 4-oxidobenzyl radical (4-OB•), which is the precursor to the HydG p-cresol byproduct. Native HydG only generates a small amount of 4-OB•, limiting detailed electron paramagnetic resonance (EPR) spectral characterization beyond our initial EPR lineshape study employing various tyrosine isotopologues. Here, we show that the concentration of trapped 4-OB• is significantly increased in reactions using HydG variants, in which the "dangler Fe" to which CO and CN- bind is missing or substituted by a redox-inert Zn2+ ion. This allows for the detailed characterization of 4-OB• using high-field EPR and electron nuclear double resonance spectroscopy to extract its g-values and 1H/13C hyperfine couplings. These results are compared to density functional theory-predicted values of several 4-OB• models with different sizes and protonation states, with a best fit to the deprotonated radical anion configuration of 4-OB•. Overall, our results depict a clearer electronic structure of the transient 4-OB• radical and provide new insights into the radical SAM chemistry of HydG.
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Affiliation(s)
- Guodong Rao
- Department of Chemistry, University of California Davis, Davis, California 95616, United States
| | - Nanhao Chen
- Department of Chemistry, University of California Davis, Davis, California 95616, United States
| | - David A Marchiori
- Department of Chemistry, University of California Davis, Davis, California 95616, United States
| | - Lee-Ping Wang
- Department of Chemistry, University of California Davis, Davis, California 95616, United States
| | - R David Britt
- Department of Chemistry, University of California Davis, Davis, California 95616, United States
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8
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Birrell JA, Rodríguez-Maciá P, Reijerse EJ, Martini MA, Lubitz W. The catalytic cycle of [FeFe] hydrogenase: A tale of two sites. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214191] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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9
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Britt RD, Rauchfuss TB. Biosynthesis of the [FeFe] hydrogenase H-cluster via a synthetic [Fe(II)(CN)(CO) 2(cysteinate)] - complex. Dalton Trans 2021; 50:12386-12391. [PMID: 34545884 DOI: 10.1039/d1dt02258j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The H-cluster of [Fe-Fe] hydrogenase consists of a [4Fe]H subcluster linked by the sulfur of a cysteine residue to an organometallic [2Fe]H subcluster that utilizes terminal CO and CN ligands to each Fe along with a bridging CO and a bridging SCH2NHCH2S azadithiolate (adt) to catalyze proton reduction or hydrogen oxidation. Three Fe-S "maturase" proteins, HydE, HydF, and HydG, are responsible for the biosynthesis of the [2Fe]H subcluster and its incorporation into the hydrogenase enzyme to form this catalytically active H-cluster. We have proposed that HydG is a bifunctional enzyme that uses S-adenosylmethione (SAM) bound to a [4Fe-4S] cluster to lyse tyrosine via a transient 5'-deoxyadenosyl radical to produce CO and CN ligands to a unique cysteine-chelated Fe(II) that is linked to a second [4Fe-4S] cluster via the cysteine sulfur. In this "synthon model", after two cycles of tyrosine lysis, the product of HydG is completed: a [Fe(CN)(CO)2(cysteinate)]- organometallic unit that is vectored directly into the synthesis of the [2Fe]H sub-cluster. However our HydG-centric synthon model is not universally accepted, so further validation is important. In this Frontiers article, we discuss recent results using a synthetic "Syn-B" complex that donates [Fe(CN)(CO)2(cysteinate)]- units that match our proposed HydG product. Can Syn-B activate hydrogenase in the absence of HydG and its tyrosine substrate? If so, since Syn-B can be synthesized with specific magnetic nuclear isotopes and with chemical substitutions, its use could allow its enzymatic conversions on the route to the H-cluster to be monitored and modeled in fresh detail.
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Affiliation(s)
- R David Britt
- Department of Chemistry, University of California Davis, Davis, CA 95616, USA.
| | - Thomas B Rauchfuss
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
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10
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Shepard EM, Impano S, Duffus BR, Pagnier A, Duschene KS, Betz JN, Byer AS, Galambas A, McDaniel EC, Watts H, McGlynn SE, Peters JW, Broderick WE, Broderick JB. HydG, the "dangler" iron, and catalytic production of free CO and CN -: implications for [FeFe]-hydrogenase maturation. Dalton Trans 2021; 50:10405-10422. [PMID: 34240096 PMCID: PMC9154046 DOI: 10.1039/d1dt01359a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The organometallic H-cluster of the [FeFe]-hydrogenase consists of a [4Fe-4S] cubane bridged via a cysteinyl thiolate to a 2Fe subcluster ([2Fe]H) containing CO, CN-, and dithiomethylamine (DTMA) ligands. The H-cluster is synthesized by three dedicated maturation proteins: the radical SAM enzymes HydE and HydG synthesize the non-protein ligands, while the GTPase HydF serves as a scaffold for assembly of [2Fe]H prior to its delivery to the [FeFe]-hydrogenase containing the [4Fe-4S] cubane. HydG uses l-tyrosine as a substrate, cleaving it to produce p-cresol as well as the CO and CN- ligands to the H-cluster, although there is some question as to whether these are formed as free diatomics or as part of a [Fe(CO)2(CN)] synthon. Here we show that Clostridium acetobutylicum (C.a.) HydG catalyzes formation of multiple equivalents of free CO at rates comparable to those for CN- formation. Free CN- is also formed in excess molar equivalents over protein. A g = 8.9 EPR signal is observed for C.a. HydG reconstituted to load the 5th "dangler" iron of the auxiliary [4Fe-4S][FeCys] cluster and is assigned to this "dangler-loaded" cluster state. Free CO and CN- formation and the degree of activation of [FeFe]-hydrogenase all occur regardless of dangler loading, but are increased 10-35% in the dangler-loaded HydG; this indicates the dangler iron is not essential to this process but may affect relevant catalysis. During HydG turnover in the presence of myoglobin, the g = 8.9 signal remains unchanged, indicating that a [Fe(CO)2(CN)(Cys)] synthon is not formed at the dangler iron. Mutation of the only protein ligand to the dangler iron, H272, to alanine nearly completely abolishes both free CO formation and hydrogenase activation, however results show this is not due solely to the loss of the dangler iron. In experiments with wild type and H272A HydG, and with different degrees of dangler loading, we observe a consistent correlation between free CO/CN- formation and hydrogenase activation. Taken in full, our results point to free CO/CN-, but not an [Fe(CO)2(CN)(Cys)] synthon, as essential species in hydrogenase maturation.
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Affiliation(s)
- Eric M Shepard
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Stella Impano
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Benjamin R Duffus
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Adrien Pagnier
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Kaitlin S Duschene
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Jeremiah N Betz
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Amanda S Byer
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Amanda Galambas
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Elizabeth C McDaniel
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Hope Watts
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Shawn E McGlynn
- Earth-Life Science Institute, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - John W Peters
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99163, USA
| | - William E Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Joan B Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA.
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11
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Li A, Yang J, Lü S, Gui MS, Yan P, Gao F, Du LB, Yang Q, Li YL. Synthesis, characterization and electrochemical properties of diiron azadithiolate complexes Fe2[(μ-SCH2)2NCH2CCH](CO)5L (L = CO or monophosphines). Polyhedron 2021. [DOI: 10.1016/j.poly.2020.115007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Impano S, Yang H, Shepard EM, Swimley R, Pagnier A, Broderick WE, Hoffman BM, Broderick JB. S-Adenosyl-l-ethionine is a Catalytically Competent Analog of S-Adenosyl-l-methione (SAM) in the Radical SAM Enzyme HydG. Angew Chem Int Ed Engl 2021; 60:4666-4672. [PMID: 33935588 PMCID: PMC8081114 DOI: 10.1002/anie.202014337] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Indexed: 01/02/2023]
Abstract
Radical S-adenosyl-l-methionine (SAM) enzymes initiate biological radical reactions with the 5'-deoxyadenosyl radical (5'-dAdo•). A [4Fe-4S]+ cluster reductively cleaves SAM to form the Ω organometallic intermediate in which the 5'-deoxyadenosyl moiety is directly bound to the unique iron of the [4Fe-4S] cluster, with subsequent liberation of 5'-dAdo•. Here we present synthesis of the SAM analog S-adenosyl-l-ethionine (SAE) and show SAE is a mechanistically-equivalent SAM-alternative for HydG, both supporting enzymatic turnover of substrate tyrosine and forming the organometallic intermediate Ω. Photolysis of SAE bound to HydG forms an ethyl radical trapped in the active site. The ethyl radical withstands prolonged storage at 77 K and its EPR signal is only partially lost upon annealing at 100 K, making it significantly less reactive than the methyl radical formed by SAM photolysis. Upon annealing above 77K, the ethyl radical adds to the [4Fe-4S]2+ cluster, generating an ethyl-[4Fe-4S]3+ organometallic species termed ΩE.
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Affiliation(s)
- Stella Impano
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
| | - Hao Yang
- Department of Chemistry, Northwestern University, Evanston, IL. USA 60208
| | - Eric M Shepard
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
| | - Ryan Swimley
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
| | - Adrien Pagnier
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
| | - William E Broderick
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
| | - Brian M Hoffman
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
| | - Joan B Broderick
- Department of Chemistry & Biochemistry, ontana State University, ozeman, MT. USA. 59717
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13
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Impano S, Yang H, Shepard EM, Swimley R, Pagnier A, Broderick WE, Hoffman BM, Broderick JB. S
‐Adenosyl‐
l
‐ethionine is a Catalytically Competent Analog of
S
‐Adenosyl‐
l
‐methionine (SAM) in the Radical SAM Enzyme HydG. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Stella Impano
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Hao Yang
- Department of Chemistry Northwestern University Evanston IL 60208 USA
| | - Eric M. Shepard
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Ryan Swimley
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Adrien Pagnier
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - William E. Broderick
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
| | - Brian M. Hoffman
- Department of Chemistry Northwestern University Evanston IL 60208 USA
| | - Joan B. Broderick
- Department of Chemistry & Biochemistry Montana State University Bozeman MT 59717 USA
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14
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Zaffaroni R, Orth N, Ivanović‐Burmazović I, Reek JNH. Hydrogenase Mimics in M 12 L 24 Nanospheres to Control Overpotential and Activity in Proton-Reduction Catalysis. Angew Chem Int Ed Engl 2020; 59:18485-18489. [PMID: 32614491 PMCID: PMC7589440 DOI: 10.1002/anie.202008298] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Indexed: 12/17/2022]
Abstract
Hydrogenase enzymes are excellent proton reduction catalysts and therefore provide clear blueprints for the development of nature-inspired synthetic analogues. Mimicking their catalytic center is straightforward but mimicking the protein matrix around the active site and all its functions remains challenging. Synthetic models lack this precisely controlled second coordination sphere that provides substrate preorganization and catalyst stability and, as a result, their performances are far from those of the natural enzyme. In this contribution, we report a strategy to easily introduce a specific yet customizable second coordination sphere around synthetic hydrogenase models by encapsulation inside M12 L24 cages and, at the same time, create a proton-rich nano-environment by co-encapsulation of ammonium salts, effectively providing substrate preorganization and intermediates stabilization. We show that catalyst encapsulation in these nanocages reduces the catalytic overpotential for proton reduction by 250 mV as compared to the uncaged catalyst, while the proton-rich nano-environment created around the catalyst ensures that high catalytic rates are maintained.
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Affiliation(s)
- Riccardo Zaffaroni
- Homogeneous, Supramolecular and Bio-Inspired Catalysisvan't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
| | - Nicole Orth
- Department of Chemistry and PharmacyFriedrich-Alexander-Universitaet ErlangenEgerlandstrasse 391058ErlangenGermany
| | - Ivana Ivanović‐Burmazović
- Department of Chemistry and PharmacyFriedrich-Alexander-Universitaet ErlangenEgerlandstrasse 391058ErlangenGermany
| | - Joost N. H. Reek
- Homogeneous, Supramolecular and Bio-Inspired Catalysisvan't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098 XHAmsterdamThe Netherlands
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15
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Zaffaroni R, Orth N, Ivanović‐Burmazović I, Reek JNH. Hydrogenase Mimics in M
12
L
24
Nanospheres to Control Overpotential and Activity in Proton‐Reduction Catalysis. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Riccardo Zaffaroni
- Homogeneous, Supramolecular and Bio-Inspired Catalysis van't Hoff Institute for Molecular Sciences University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Nicole Orth
- Department of Chemistry and Pharmacy Friedrich-Alexander-Universitaet Erlangen Egerlandstrasse 3 91058 Erlangen Germany
| | - Ivana Ivanović‐Burmazović
- Department of Chemistry and Pharmacy Friedrich-Alexander-Universitaet Erlangen Egerlandstrasse 3 91058 Erlangen Germany
| | - Joost N. H. Reek
- Homogeneous, Supramolecular and Bio-Inspired Catalysis van't Hoff Institute for Molecular Sciences University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
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16
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Britt RD, Rao G, Tao L. Biosynthesis of the catalytic H-cluster of [FeFe] hydrogenase: the roles of the Fe-S maturase proteins HydE, HydF, and HydG. Chem Sci 2020; 11:10313-10323. [PMID: 34123177 PMCID: PMC8162317 DOI: 10.1039/d0sc04216a] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/11/2020] [Indexed: 11/22/2022] Open
Abstract
[FeFe] hydrogenases carry out the redox interconversion of protons and molecular hydrogen (2H+ + 2e- ⇌ H2) at a complex Fe-S active site known as the H-cluster. The H-cluster consists of a [4Fe-4S] subcluster, denoted here as [4Fe]H, linked via a cysteine sulfur to an interesting organometallic [2Fe]H subcluster thought to be the subsite where the catalysis occurs. This [2Fe]H subcluster consists of two Fe atoms, linked with a bridging CO and a bridging SCH2NHCH2S azadithiolate (adt), with additional terminal CO and CN ligands bound to each Fe. Synthesizing such a complex organometallic unit is a fascinating problem in biochemistry, complicated by the toxic nature of both the CO and CN- species and the relative fragility of the azadithiolate bridge. It has been known for a number of years that this complex biosynthesis is carried out by a set of three essential Fe-S proteins, HydE, HydF, and HydG. HydF is a GTPase, while HydE and HydG are both members of the large family of radical S-adenosylmethionine (rSAM) enzymes. In this perspective we describe the history of research and discovery concerning these three Fe-S "maturase" proteins and describe recent evidence for a sequential biosynthetic pathway beginning with the synthesis of a mononuclear organometallic [Fe(ii)(CO)2CN(cysteine)] complex by the rSAM enzyme HydG and its subsequent activation by the second rSAM enzyme HydE to form a highly reactive Fe(i)(CO)2(CN)S species. In our model a pair of these Fe(i)(CO)2(CN)S units condense to form the [Fe(CO)2(CN)S]2 diamond core of the [2Fe]H cluster, requiring only the installation of the central CH2NHCH2 portion of the azadithiolate bridge, whose atoms are all sourced from the amino acid serine. This final step likely occurs with an interplay of HydE and HydF, the details of which yet remain to be elucidated.
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Affiliation(s)
- R David Britt
- Department of Chemistry, University of California, Davis Davis CA 95616 USA
| | - Guodong Rao
- Department of Chemistry, University of California, Davis Davis CA 95616 USA
| | - Lizhi Tao
- Department of Chemistry, University of California, Davis Davis CA 95616 USA
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17
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Németh B, Land H, Magnuson A, Hofer A, Berggren G. The maturase HydF enables [FeFe] hydrogenase assembly via transient, cofactor-dependent interactions. J Biol Chem 2020; 295:11891-11901. [PMID: 32620553 PMCID: PMC7450098 DOI: 10.1074/jbc.ra119.011419] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 06/25/2020] [Indexed: 12/24/2022] Open
Abstract
[FeFe] hydrogenases have attracted extensive attention in the field of renewable energy research because of their remarkable efficiency for H2 gas production. H2 formation is catalyzed by a biologically unique hexanuclear iron cofactor denoted the H-cluster. The assembly of this cofactor requires a dedicated maturation machinery including HydF, a multidomain [4Fe4S] cluster protein with GTPase activity. HydF is responsible for harboring and delivering a precatalyst to the apo-hydrogenase, but the details of this process are not well understood. Here, we utilize gas-phase electrophoretic macromolecule analysis to show that a HydF dimer forms a transient interaction complex with the hydrogenase and that the formation of this complex depends on the cofactor content on HydF. Moreover, Fourier transform infrared, electron paramagnetic resonance, and UV-visible spectroscopy studies of mutants of HydF show that the isolated iron-sulfur cluster domain retains the capacity for binding the precatalyst in a reversible fashion and is capable of activating apo-hydrogenase in in vitro assays. These results demonstrate the central role of the iron-sulfur cluster domain of HydF in the final stages of H-cluster assembly, i.e. in binding and delivering the precatalyst.
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Affiliation(s)
- Brigitta Németh
- Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Henrik Land
- Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Ann Magnuson
- Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Anders Hofer
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Gustav Berggren
- Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
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18
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Németh B, Senger M, Redman HJ, Ceccaldi P, Broderick J, Magnuson A, Stripp ST, Haumann M, Berggren G. [FeFe]-hydrogenase maturation: H-cluster assembly intermediates tracked by electron paramagnetic resonance, infrared, and X-ray absorption spectroscopy. J Biol Inorg Chem 2020; 25:777-788. [PMID: 32661785 PMCID: PMC7399679 DOI: 10.1007/s00775-020-01799-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/09/2020] [Indexed: 11/25/2022]
Abstract
[FeFe]-hydrogenase enzymes employ a unique organometallic cofactor for efficient and reversible hydrogen conversion. This so-called H-cluster consists of a [4Fe-4S] cubane cysteine linked to a diiron complex coordinated by carbon monoxide and cyanide ligands and an azadithiolate ligand (adt = NH(CH2S)2)·[FeFe]-hydrogenase apo-protein binding only the [4Fe-4S] sub-complex can be fully activated in vitro by the addition of a synthetic diiron site precursor complex ([2Fe]adt). Elucidation of the mechanism of cofactor assembly will aid in the design of improved hydrogen processing synthetic catalysts. We combined electron paramagnetic resonance, Fourier-transform infrared, and X-ray absorption spectroscopy to characterize intermediates of H-cluster assembly as initiated by mixing of the apo-protein (HydA1) from the green alga Chlamydomonas reinhardtii with [2Fe]adt. The three methods consistently show rapid formation of a complete H-cluster in the oxidized, CO-inhibited state (Hox-CO) already within seconds after the mixing. Moreover, FTIR spectroscopy support a model in which Hox-CO formation is preceded by a short-lived Hred'-CO-like intermediate. Accumulation of Hox-CO was followed by CO release resulting in the slower conversion to the catalytically active state (Hox) as well as formation of reduced states of the H-cluster.
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Affiliation(s)
- Brigitta Németh
- Department of Chemistry, Ångström Laboratory, Molecular Biomimetics, Uppsala University, 75120, Uppsala, Sweden
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA
| | - Moritz Senger
- Physics Department, Molecular Biophysics, Freie Universität Berlin, 14195, Berlin, Germany
- Department of Chemistry, Ångström Laboratory, Physical Chemistry, Uppsala University, 75120, Uppsala, Sweden
| | - Holly J Redman
- Department of Chemistry, Ångström Laboratory, Molecular Biomimetics, Uppsala University, 75120, Uppsala, Sweden
| | - Pierre Ceccaldi
- Department of Chemistry, Ångström Laboratory, Molecular Biomimetics, Uppsala University, 75120, Uppsala, Sweden
| | - Joan Broderick
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA
| | - Ann Magnuson
- Department of Chemistry, Ångström Laboratory, Molecular Biomimetics, Uppsala University, 75120, Uppsala, Sweden
| | - Sven T Stripp
- Physics Department, Molecular Biophysics, Freie Universität Berlin, 14195, Berlin, Germany
| | - Michael Haumann
- Physics Department, Biophysics of Metalloenzymes, Freie Universität Berlin, 14195, Berlin, Germany
| | - Gustav Berggren
- Department of Chemistry, Ångström Laboratory, Molecular Biomimetics, Uppsala University, 75120, Uppsala, Sweden.
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19
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20
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Tao L, Pattenaude SA, Joshi S, Begley TP, Rauchfuss TB, Britt RD. Radical SAM Enzyme HydE Generates Adenosylated Fe(I) Intermediates En Route to the [FeFe]-Hydrogenase Catalytic H-Cluster. J Am Chem Soc 2020; 142:10841-10848. [PMID: 32434327 PMCID: PMC7440672 DOI: 10.1021/jacs.0c03802] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The H-cluster of [FeFe]-hydrogenase consists of a [4Fe-4S]H-subcluster linked by a cysteinyl bridge to a unique organometallic [2Fe]H-subcluster assigned as the site of interconversion between protons and molecular hydrogen. This [2Fe]H-subcluster is assembled by a set of Fe-S maturase enzymes HydG, HydE and HydF. Here we show that the HydG product [FeII(Cys)(CO)2(CN)] synthon is the substrate of the radical SAM enzyme HydE, with the generated 5'-deoxyadenosyl radical attacking the cysteine S to form a C5'-S bond concomitant with reduction of the central low-spin Fe(II) to the Fe(I) oxidation state. This leads to the cleavage of the cysteine C3-S bond, producing a mononuclear [FeI(CO)2(CN)S] species that serves as the precursor to the dinuclear Fe(I)Fe(I) center of the [2Fe]H-subcluster. This work unveils the role played by HydE in the enzymatic assembly of the H-cluster and expands the scope of radical SAM enzyme chemistry.
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Affiliation(s)
- Lizhi Tao
- Department of Chemistry, University of California at Davis, Davis, California 95616, United States
| | - Scott A Pattenaude
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Sumedh Joshi
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Tadhg P Begley
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Thomas B Rauchfuss
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - R David Britt
- Department of Chemistry, University of California at Davis, Davis, California 95616, United States
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21
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Mészáros LS, Ceccaldi P, Lorenzi M, Redman HJ, Pfitzner E, Heberle J, Senger M, Stripp ST, Berggren G. Spectroscopic investigations under whole-cell conditions provide new insight into the metal hydride chemistry of [FeFe]-hydrogenase. Chem Sci 2020; 11:4608-4617. [PMID: 34122916 PMCID: PMC8159234 DOI: 10.1039/d0sc00512f] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Hydrogenases are among the fastest H2 evolving catalysts known to date and have been extensively studied under in vitro conditions. Here, we report the first mechanistic investigation of an [FeFe]-hydrogenase under whole-cell conditions. Functional [FeFe]-hydrogenase from the green alga Chlamydomonas reinhardtii is generated in genetically modified Escherichia coli cells by addition of a synthetic cofactor to the growth medium. The assembly and reactivity of the resulting semi-synthetic enzyme was monitored using whole-cell electron paramagnetic resonance and Fourier-transform Infrared difference spectroscopy as well as scattering scanning near-field optical microscopy. Through a combination of gas treatments, pH titrations, and isotope editing we were able to corroborate the formation of a number of proposed catalytic intermediates in living cells, supporting their physiological relevance. Moreover, a previously incompletely characterized catalytic intermediate is reported herein, attributed to the formation of a protonated metal hydride species.
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Affiliation(s)
- Lívia S Mészáros
- Molecular Biomimetics, Dept. of Chemistry - Ångström Laboratory, Uppsala University Lägerhyddsvägen 1 SE-75120 Uppsala Sweden
| | - Pierre Ceccaldi
- Molecular Biomimetics, Dept. of Chemistry - Ångström Laboratory, Uppsala University Lägerhyddsvägen 1 SE-75120 Uppsala Sweden
| | - Marco Lorenzi
- Molecular Biomimetics, Dept. of Chemistry - Ångström Laboratory, Uppsala University Lägerhyddsvägen 1 SE-75120 Uppsala Sweden
| | - Holly J Redman
- Molecular Biomimetics, Dept. of Chemistry - Ångström Laboratory, Uppsala University Lägerhyddsvägen 1 SE-75120 Uppsala Sweden
| | - Emanuel Pfitzner
- Institute of Experimental Physics, Experimental Molecular Biophysics, Freie Universität Berlin Arnimallee 14 Berlin DE-14195 Germany
| | - Joachim Heberle
- Institute of Experimental Physics, Experimental Molecular Biophysics, Freie Universität Berlin Arnimallee 14 Berlin DE-14195 Germany
| | - Moritz Senger
- Institute of Experimental Physics, Experimental Molecular Biophysics, Freie Universität Berlin Arnimallee 14 Berlin DE-14195 Germany
| | - Sven T Stripp
- Institute of Experimental Physics, Experimental Molecular Biophysics, Freie Universität Berlin Arnimallee 14 Berlin DE-14195 Germany
| | - Gustav Berggren
- Molecular Biomimetics, Dept. of Chemistry - Ångström Laboratory, Uppsala University Lägerhyddsvägen 1 SE-75120 Uppsala Sweden
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22
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Adenosylation reactions catalyzed by the radical S-adenosylmethionine superfamily enzymes. Curr Opin Chem Biol 2020; 55:86-95. [DOI: 10.1016/j.cbpa.2020.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/22/2019] [Accepted: 01/15/2020] [Indexed: 01/23/2023]
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23
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Rao G, Tao L, Britt RD. Serine is the molecular source of the NH(CH 2) 2 bridgehead moiety of the in vitro assembled [FeFe] hydrogenase H-cluster. Chem Sci 2019; 11:1241-1247. [PMID: 34123248 PMCID: PMC8148037 DOI: 10.1039/c9sc05900h] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The active site of [FeFe] hydrogenase, the H-cluster, consists of a canonical [4Fe–4S]H subcluster linked to a unique binuclear [2Fe]H subcluster containing three CO, two CN− and a bridging azadithiolate (adt, NH(CH2S−)2) ligand. While it is known that all five diatomic ligands are derived from tyrosine, there has been little knowledge as to the formation and installation of the adt ligand. Here, by using a combination of a cell-free in vitro maturation approach with pulse electronic paramagnetic resonance spectroscopy, we discover that serine donates the nitrogen atom and the CH2 group to the assembly of the adt ligand. More specifically, both CH2 groups in adt are sourced from the C3 methylene of serine. The CH2NHCH2 bridgehead moiety of the [FeFe] hydrogenase H-cluster is derived from serine as revealed by isotope labeling and EPR spectroscopy.![]()
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Affiliation(s)
- Guodong Rao
- Department of Chemistry, University of California Davis CA 95616 USA
| | - Lizhi Tao
- Department of Chemistry, University of California Davis CA 95616 USA
| | - R David Britt
- Department of Chemistry, University of California Davis CA 95616 USA
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24
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Sayler R, Stich TA, Joshi S, Cooper N, Shaw JT, Begley TP, Tantillo DJ, Britt RD. Trapping and Electron Paramagnetic Resonance Characterization of the 5'dAdo • Radical in a Radical S-Adenosyl Methionine Enzyme Reaction with a Non-Native Substrate. ACS CENTRAL SCIENCE 2019; 5:1777-1785. [PMID: 31807679 PMCID: PMC6891858 DOI: 10.1021/acscentsci.9b00706] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Indexed: 05/03/2023]
Abstract
S-Adenosyl methionine (SAM) is employed as a [4Fe-4S]-bound cofactor in the superfamily of radical SAM (rSAM) enzymes, in which one-electron reduction of the [4Fe-4S]-SAM moiety leads to homolytic cleavage of the S-adenosyl methionine to generate the 5'-deoxyadenosyl radical (5'dAdo•), a potent H-atom abstractor. HydG, a member of this rSAM family, uses the 5'dAdo• radical to lyse its substrate, tyrosine, producing CO and CN that bind to a unique Fe site of a second HydG Fe-S cluster, ultimately producing a mononuclear organometallic Fe-l-cysteine-(CO)2CN complex as an intermediate in the bioassembly of the catalytic H-cluster of [Fe-Fe] hydrogenase. Here we report the use of non-native tyrosine substrate analogues to further probe the initial radical chemistry of HydG. One such non-native substrate is 4-hydroxy phenyl propanoic acid (HPPA) which lacks the amino group of tyrosine, replacing the CαH-NH2 with a CH2 at the C2 position. Electron paramagnetic resonance (EPR) studies show the generation of a strong and relatively stable radical in the HydG reaction with natural abundance and 13C2-HPPA, with appreciable spin density localized at C2. These results led us to try parallel experiments with the more oxidized non-native substrate coumaric acid, which has a C2=C3 alkene substitution relative to HPPA's single bond. Interestingly, the HydG reaction with the cis-p-coumaric acid isomer led to the trapping of a new radical EPR signal, and EPR studies using cis-p-coumaric acid along with isotopically labeled SAM reveal that we have for the first time trapped and characterized the 5'dAdo• radical in an actual rSAM enzyme reaction, here by using this specific non-native substrate cis-p-coumaric acid. Density functional theory energetics calculations show that the cis-p-coumaric acid has approximately the same C-H bond dissociation free energy as 5'dAdo•, providing a possible explanation for our ability to trap an appreciable fraction of 5'dAdo• in this specific rSAM reaction. The radical's EPR line shape and its changes with SAM isotopic substitution are nearly identical to those of a 5'dAdo• radical recently generated by cryophotolysis of a prereduced [4Fe-4S]-SAM center in another rSAM enzyme, pyruvate formate-lyase activating enzyme, further supporting our assignment that we have indeed trapped and characterized the 5'dAdo• radical in a radical SAM enzymatic reaction by appropriate tuning of the relative radical free energies via the judicious selection of a non-native substrate.
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Affiliation(s)
- Richard
I. Sayler
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United States
| | - Troy A. Stich
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United States
| | - Sumedh Joshi
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Nicole Cooper
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United States
| | - Jared T. Shaw
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United States
| | - Tadhg P. Begley
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Dean J. Tantillo
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United States
| | - R. David Britt
- Department
of Chemistry, University of California,
Davis, Davis, California 95616, United States
- E-mail: . Phone: (530) 752
6377
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25
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The binuclear cluster of [FeFe] hydrogenase is formed with sulfur donated by cysteine of an [Fe(Cys)(CO) 2(CN)] organometallic precursor. Proc Natl Acad Sci U S A 2019; 116:20850-20855. [PMID: 31570604 DOI: 10.1073/pnas.1913324116] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The enzyme [FeFe]-hydrogenase (HydA1) contains a unique 6-iron cofactor, the H-cluster, that has unusual ligands to an Fe-Fe binuclear subcluster: CN-, CO, and an azadithiolate (adt) ligand that provides 2 S bridges between the 2 Fe atoms. In cells, the H-cluster is assembled by a collection of 3 maturases: HydE and HydF, whose roles aren't fully understood, and HydG, which has been shown to construct a [Fe(Cys)(CO)2(CN)] organometallic precursor to the binuclear cluster. Here, we report the in vitro assembly of the H-cluster in the absence of HydG, which is functionally replaced by adding a synthetic [Fe(Cys)(CO)2(CN)] carrier in the maturation reaction. The synthetic carrier and the HydG-generated analog exhibit similar infrared spectra. The carrier allows HydG-free maturation to HydA1, whose activity matches that of the native enzyme. Maturation with 13CN-containing carrier affords 13CN-labeled enzyme as verified by electron paramagnetic resonance (EPR)/electron nuclear double-resonance spectra. This synthetic surrogate approach complements existing biochemical strategies and greatly facilitates the understanding of pathways involved in the assembly of the H-cluster. As an immediate demonstration, we clarify that Cys is not the source of the carbon and nitrogen atoms in the adt ligand using pulse EPR to target the magnetic couplings introduced via a 13C3,15N-Cys-labeled synthetic carrier. Parallel mass-spectrometry experiments show that the Cys backbone is converted to pyruvate, consistent with a cysteine role in donating S in forming the adt bridge. This mechanistic scenario is confirmed via maturation with a seleno-Cys carrier to form HydA1-Se, where the incorporation of Se was characterized by extended X-ray absorption fine structure spectroscopy.
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26
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H-cluster assembly intermediates built on HydF by the radical SAM enzymes HydE and HydG. J Biol Inorg Chem 2019; 24:783-792. [PMID: 31493152 DOI: 10.1007/s00775-019-01709-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 08/13/2019] [Indexed: 12/12/2022]
Abstract
[FeFe]-hydrogenase catalyzes the reversible reduction of protons to H2 at a complex metallocofactor site, the H-cluster. Biosynthesis of this active-site H-cluster requires three maturation enzymes: the radical S-adenosylmethionine enzymes HydE and HydG synthesize the nonprotein ligands, while the GTPase HydF provides a scaffold for assembly of the 2Fe subcluster of the H-cluster ([2Fe]H) prior to its transfer to hydrogenase. To delineate the assembly and delivery steps for the 2Fe precursor cluster coordinated to HydF ([2Fe]F), we have heterologously expressed HydF in the presence of HydE alone (HydFE) or HydG alone (HydFG), and characterized the resulting purified HydFE and HydFG using UV-visible, EPR, and FTIR spectroscopies and biochemical assays. The iron-sulfur clusters on HydF are modified by co-expression with HydE or HydG, as evidenced by the changes in the visible, EPR, and FTIR spectral features. Further, biochemical assays show that HydFE is capable of activating HydAΔEFG to a limited extent (~ 1% of WT) even though the normal source of CO and CN- ligands of [2Fe]H (HydG) was absent. Activation assays performed with HydFG, in contrast, exhibit no ability to mature HydAΔEFG. It appears that in the case of HydFE, trace diatomics from the cellular environment are incorporated into a [2Fe]F-like precursor on HydF in the absence of HydG. We conclude that the product of HydE, presumably the dithiomethylamine ligand of [2Fe]H, is absolutely essential to the activation process, while the diatomic products of HydG can be provided from alternate sources.
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27
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Bai Y, Chen T, Happe T, Lu Y, Sawyer A. Iron-sulphur cluster biogenesis via the SUF pathway. Metallomics 2019; 10:1038-1052. [PMID: 30019043 DOI: 10.1039/c8mt00150b] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Iron-sulphur (Fe-S) clusters are versatile cofactors, which are essential for key metabolic processes in cells, such as respiration and photosynthesis, and which may have also played a crucial role in establishing life on Earth. They can be found in almost all living organisms, from unicellular prokaryotes and archaea to multicellular animals and plants, and exist in diverse forms. This review focuses on the most ancient Fe-S cluster assembly system, the sulphur utilization factor (SUF) mechanism, which is crucial in bacteria for cell survival under stress conditions such as oxidation and iron starvation, and which is also present in the chloroplasts of green microalgae and plants, where it is responsible for plastidial Fe-S protein maturation. We explain the SUF Fe-S cluster assembly process, the proteins involved, their regulation and provide evolutionary insights. We specifically focus on examples from Fe-S cluster synthesis in the model organisms Escherichia coli and Arabidopsis thaliana and discuss in an in vivo context the assembly of the [FeFe]-hydrogenase H-cluster from Chlamydomonas reinhardtii.
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Affiliation(s)
- Y Bai
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
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28
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Baffert C, Kpebe A, Avilan L, Brugna M. Hydrogenases and H 2 metabolism in sulfate-reducing bacteria of the Desulfovibrio genus. Adv Microb Physiol 2019; 74:143-189. [PMID: 31126530 DOI: 10.1016/bs.ampbs.2019.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hydrogen metabolism plays a central role in sulfate-reducing bacteria of the Desulfovibrio genus and is based on hydrogenases that catalyze the reversible conversion of protons into dihydrogen. These metabolically versatile microorganisms possess a complex hydrogenase system composed of several enzymes of both [FeFe]- and [NiFe]-type that can vary considerably from one Desulfovibrio species to another. This review covers the molecular and physiological aspects of hydrogenases and H2 metabolism in Desulfovibrio but focuses particularly on our model bacterium Desulfovibrio fructosovorans. The search of hydrogenase genes in more than 30 sequenced genomes provides an overview of the distribution of these enzymes in Desulfovibrio. Our discussion will consider the significance of the involvement of electron-bifurcation in H2 metabolism.
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Affiliation(s)
- Carole Baffert
- Aix-Marseille University, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Arlette Kpebe
- Aix-Marseille University, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Luisana Avilan
- Aix-Marseille University, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Myriam Brugna
- Aix-Marseille University, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille, France
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29
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Wen N, Zhang L, Lin JD, Feng YN, Cao J, Wen CL, Wei Y. Diiron models for active site of FeFe-hydrogenase armed with one or two chlorine butynyl groups: Synthesis, structures and electrochemistry. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.11.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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30
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Wu Y, Wu R, Mandalapu D, Ji X, Chen T, Ding W, Zhang Q. Radical SAM-dependent adenosylation catalyzed by l-tyrosine lyases. Org Biomol Chem 2019; 17:1809-1812. [DOI: 10.1039/c8ob02906g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Tyrosine analogues containing an olefin moiety can be adenosylated by l-tyrosine lyases.
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Affiliation(s)
- Yujie Wu
- State Key Laboratory of Cryospheric Sciences
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering
- Northwest Institute of Eco-environment and Resource
- Chinese Academy of Sciences
- Lanzhou 730000
| | - Runze Wu
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | | | - Xinjian Ji
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Tuo Chen
- State Key Laboratory of Cryospheric Sciences
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering
- Northwest Institute of Eco-environment and Resource
- Chinese Academy of Sciences
- Lanzhou 730000
| | - Wei Ding
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Qi Zhang
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
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31
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Clostridial whole cell and enzyme systems for hydrogen production: current state and perspectives. Appl Microbiol Biotechnol 2018; 103:567-575. [PMID: 30446778 DOI: 10.1007/s00253-018-9514-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/06/2018] [Accepted: 11/09/2018] [Indexed: 10/27/2022]
Abstract
Strictly anaerobic bacteria of the Clostridium genus have attracted great interest as potential cell factories for molecular hydrogen production purposes. In addition to being a useful approach to this process, dark fermentation has the advantage of using the degradation of cheap agricultural residues and industrial wastes for molecular hydrogen production. However, many improvements are still required before large-scale hydrogen production from clostridial metabolism is possible. Here we review the literature on the basic biological processes involved in clostridial hydrogen production, and present the main advances obtained so far in order to enhance the hydrogen productivity, as well as suggesting some possible future prospects.
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32
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Scott AG, Szilagyi RK, Mulder DW, Ratzloff MW, Byer AS, King PW, Broderick WE, Shepard EM, Broderick JB. Compositional and structural insights into the nature of the H-cluster precursor on HydF. Dalton Trans 2018; 47:9521-9535. [PMID: 29964288 DOI: 10.1039/c8dt01654b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Assembly of an active [FeFe]-hydrogenase requires dedicated maturation enzymes that generate the active-site H-cluster: the radical SAM enzymes HydE and HydG synthesize the unusual non-protein ligands - carbon monoxide, cyanide, and dithiomethylamine - while the GTPase HydF serves as a scaffold for assembly of the 2Fe subcluster containing these ligands. In the current study, enzymatically cluster-loaded HydF ([2Fe]F) is produced by co-expression with HydE and HydG in an Escherichia coli host followed by isolation and examination by FTIR and EPR spectroscopy. FTIR reveals the presence of well-defined terminal CO and CN- ligands; however, unlike in the [FeFe]-hydrogenase, no bridging CO is observed. Exposure of this loaded HydF to exogenous CO or H2 produces no significant changes to the FTIR spectrum, indicating that, unlike in the [FeFe]-hydrogenase, the 2Fe cluster in loaded HydF is coordinatively saturated and relatively unreactive. EPR spectroscopy reveals the presence of both [4Fe-4S] and [2Fe-2S] clusters on this loaded HydF, but provides no direct evidence for these being linked to the [2Fe]F. Using the chemical reactivity and FTIR data, a large collection of computational models were evaluated. Their scaled quantum chemical vibrational spectra allowed us to score various [2Fe]F structures in terms of their ability to reproduce the diatomic stretching frequencies observed in the FTIR experimental spectra. Collectively, the results provide new insights that support the presence of a diamagnetic, but spin-polarized FeI-FeI oxidation state for the [2Fe]F precursor cluster that is coordinated by 4 CO and 2 CN- ligands, and bridged to an adjacent iron-sulfur cluster through one of the CN- ligands.
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Affiliation(s)
- Anna G Scott
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA.
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33
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Zanello P. Structure and electrochemistry of proteins harboring iron-sulfur clusters of different nuclearities. Part II. [4Fe-4S] and [3Fe-4S] iron-sulfur proteins. J Struct Biol 2018; 202:250-263. [DOI: 10.1016/j.jsb.2018.01.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 01/11/2018] [Accepted: 01/29/2018] [Indexed: 01/27/2023]
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34
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A [4Fe-4S]-Fe(CO)(CN)-L-cysteine intermediate is the first organometallic precursor in [FeFe] hydrogenase H-cluster bioassembly. Nat Chem 2018; 10:555-560. [PMID: 29632334 PMCID: PMC6380689 DOI: 10.1038/s41557-018-0026-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 02/14/2018] [Indexed: 12/27/2022]
Abstract
Biosynthesis of the [FeFe] hydrogenase active site (the 'H-cluster') requires the interplay of multiple proteins and small molecules. Among them, the radical S-adenosylmethionine enzyme HydG, a tyrosine lyase, has been proposed to generate a complex that contains an Fe(CO)2(CN) moiety that is eventually incorporated into the H-cluster. Here we describe the characterization of an intermediate in the HydG reaction: a [4Fe-4S][(Cys)Fe(CO)(CN)] species, 'Complex A', in which a CO, a CN- and a cysteine (Cys) molecule bind to the unique 'dangler' Fe site of the auxiliary [5Fe-4S] cluster of HydG. The identification of this intermediate-the first organometallic precursor to the H-cluster-validates the previously hypothesized HydG reaction cycle and provides a basis for elucidating the biosynthetic origin of other moieties of the H-cluster.
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35
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Esmieu C, Raleiras P, Berggren G. From protein engineering to artificial enzymes - biological and biomimetic approaches towards sustainable hydrogen production. SUSTAINABLE ENERGY & FUELS 2018; 2:724-750. [PMID: 31497651 PMCID: PMC6695573 DOI: 10.1039/c7se00582b] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 01/31/2018] [Indexed: 06/09/2023]
Abstract
Hydrogen gas is used extensively in industry today and is often put forward as a suitable energy carrier due its high energy density. Currently, the main source of molecular hydrogen is fossil fuels via steam reforming. Consequently, novel production methods are required to improve the sustainability of hydrogen gas for industrial processes, as well as paving the way for its implementation as a future solar fuel. Nature has already developed an elaborate hydrogen economy, where the production and consumption of hydrogen gas is catalysed by hydrogenase enzymes. In this review we summarize efforts on engineering and optimizing these enzymes for biological hydrogen gas production, with an emphasis on their inorganic cofactors. Moreover, we will describe how our understanding of these enzymes has been applied for the preparation of bio-inspired/-mimetic systems for efficient and sustainable hydrogen production.
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Affiliation(s)
- C Esmieu
- Department of Chemistry , Ångström Laboratory , Uppsala University , Box 523 , SE-75120 Uppsala , Sweden .
| | - P Raleiras
- Department of Chemistry , Ångström Laboratory , Uppsala University , Box 523 , SE-75120 Uppsala , Sweden .
| | - G Berggren
- Department of Chemistry , Ångström Laboratory , Uppsala University , Box 523 , SE-75120 Uppsala , Sweden .
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36
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Mészáros LS, Németh B, Esmieu C, Ceccaldi P, Berggren G. In Vivo EPR Characterization of Semi-Synthetic [FeFe] Hydrogenases. Angew Chem Int Ed Engl 2018; 57:2596-2599. [PMID: 29334424 PMCID: PMC6282530 DOI: 10.1002/anie.201710740] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 12/18/2018] [Indexed: 01/18/2023]
Abstract
EPR spectroscopy reveals the formation of two different semi-synthetic hydrogenases in vivo. [FeFe] hydrogenases are metalloenzymes that catalyze the interconversion of molecular hydrogen and protons. The reaction is catalyzed by the H-cluster, consisting of a canonical iron-sulfur cluster and an organometallic [2Fe] subsite. It was recently shown that the enzyme can be reconstituted with synthetic cofactors mimicking the composition of the [2Fe] subsite, resulting in semi-synthetic hydrogenases. Herein, we employ EPR spectroscopy to monitor the formation of two such semi-synthetic enzymes in whole cells. The study provides the first spectroscopic characterization of semi-synthetic hydrogenases in vivo, and the observation of two different oxidized states of the H-cluster under intracellular conditions. Moreover, these findings underscore how synthetic chemistry can be a powerful tool for manipulation and examination of the hydrogenase enzyme under in vivo conditions.
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Affiliation(s)
- Lívia S. Mészáros
- Department of Chemistry—Uppsala UniversityLägerhyddsvägen 175120UppsalaSweden
| | - Brigitta Németh
- Department of Chemistry—Uppsala UniversityLägerhyddsvägen 175120UppsalaSweden
| | - Charlène Esmieu
- Department of Chemistry—Uppsala UniversityLägerhyddsvägen 175120UppsalaSweden
| | - Pierre Ceccaldi
- Department of Chemistry—Uppsala UniversityLägerhyddsvägen 175120UppsalaSweden
| | - Gustav Berggren
- Department of Chemistry—Uppsala UniversityLägerhyddsvägen 175120UppsalaSweden
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37
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Mészáros LS, Németh B, Esmieu C, Ceccaldi P, Berggren G. In Vivo EPR Characterization of Semi-Synthetic [FeFe] Hydrogenases. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201710740] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Lívia S. Mészáros
- Department of Chemistry-; Uppsala University; Lägerhyddsvägen 1 75120 Uppsala Sweden
| | - Brigitta Németh
- Department of Chemistry-; Uppsala University; Lägerhyddsvägen 1 75120 Uppsala Sweden
| | - Charlène Esmieu
- Department of Chemistry-; Uppsala University; Lägerhyddsvägen 1 75120 Uppsala Sweden
| | - Pierre Ceccaldi
- Department of Chemistry-; Uppsala University; Lägerhyddsvägen 1 75120 Uppsala Sweden
| | - Gustav Berggren
- Department of Chemistry-; Uppsala University; Lägerhyddsvägen 1 75120 Uppsala Sweden
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38
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Zaffaroni R, Detz RJ, van der Vlugt JI, Reek JNH. A Functional Hydrogenase Mimic Chemisorbed onto Fluorine-Doped Tin Oxide Electrodes: A Strategy towards Water Splitting Devices. CHEMSUSCHEM 2018; 11:209-218. [PMID: 29077275 PMCID: PMC5814736 DOI: 10.1002/cssc.201701757] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 10/26/2017] [Indexed: 06/07/2023]
Abstract
A diiron benzenedithiolate hydrogen-evolving catalyst immobilized onto fluorine-doped tin oxide (FTO) electrodes is prepared, characterized, and studied in the context of the development of water splitting devices based on molecular components. FTO was chosen as the preferred electrode material owing to its conductive properties and electrochemical stability. An FTO nanocrystalline layer is also used to greatly improve the surface area of commercially available FTO while preserving the properties of the material. Electrodes bearing a covalently anchored diiron catalyst are shown to be competent for electrocatalytic hydrogen evolution from acidic aqueous media at relatively low overpotential (500 mV) with a faradaic efficiency close to unity. Compared with bulk solution catalysts, the catalyst immobilized onto the electrode surface operates at roughly 160 mV lower overpotentials, yet with similar rates.
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Affiliation(s)
- Riccardo Zaffaroni
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
| | - Remko J. Detz
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
| | - Jarl Ivar van der Vlugt
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
| | - Joost N. H. Reek
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041098XHAmsterdamThe Netherlands
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39
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Chongdar N, Birrell JA, Pawlak K, Sommer C, Reijerse EJ, Rüdiger O, Lubitz W, Ogata H. Unique Spectroscopic Properties of the H-Cluster in a Putative Sensory [FeFe] Hydrogenase. J Am Chem Soc 2018; 140:1057-1068. [PMID: 29251926 DOI: 10.1021/jacs.7b11287] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sensory type [FeFe] hydrogenases are predicted to play a role in transcriptional regulation by detecting the H2 level of the cellular environment. These hydrogenases contain the hydrogenase domain with distinct modifications in the active site pocket, followed by a Per-Arnt-Sim (PAS) domain. As yet, neither the physiological function nor the biochemical or spectroscopic properties of these enzymes have been explored. Here, we present the characterization of an artificially maturated, putative sensory [FeFe] hydrogenase from Thermotoga maritima (HydS). This enzyme shows lower hydrogen conversion activity than prototypical [FeFe] hydrogenases and a reduced inhibition by CO. Using FTIR spectroelectrochemistry and EPR spectroscopy, three redox states of the active site were identified. The spectroscopic signatures of the most oxidized state closely resemble those of the Hox state from the prototypical [FeFe] hydrogenases, while the FTIR spectra of both singly and doubly reduced states show large differences. The FTIR bands of both the reduced states are strongly red-shifted relative to the Hox state, indicating reduction at the diiron site, but with retention of the bridging CO ligand. The unique functional and spectroscopic features of HydS are discussed with regard to the possible role of altered amino acid residues influencing the electronic properties of the H-cluster.
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Affiliation(s)
- Nipa Chongdar
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - Krzysztof Pawlak
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - Constanze Sommer
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - Edward J Reijerse
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany
| | - Hideaki Ogata
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D45470 Mülheim an der Ruhr, Germany.,Institute of Low Temperature Science, Hokkaido University , Kita19 Nishi8, Kita-ku, 060-0819 Sapporo, Japan
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40
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Shepard EM, Byer AS, Broderick JB. Iron-Sulfur Cluster States of the Hydrogenase Maturase HydF. Biochemistry 2017; 56:4733-4734. [PMID: 28853860 DOI: 10.1021/acs.biochem.7b00735] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Eric M Shepard
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Amanda S Byer
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Joan B Broderick
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
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41
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Artz JH, Zadvornyy OA, Mulder DW, King PW, Peters JW. Structural Characterization of Poised States in the Oxygen Sensitive Hydrogenases and Nitrogenases. Methods Enzymol 2017; 595:213-259. [PMID: 28882202 DOI: 10.1016/bs.mie.2017.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The crystallization of FeS cluster-containing proteins has been challenging due to their oxygen sensitivity, and yet these enzymes are involved in many critical catalytic reactions. The last few years have seen a wealth of innovative experiments designed to elucidate not just structural but mechanistic insights into FeS cluster enzymes. Here, we focus on the crystallization of hydrogenases, which catalyze the reversible reduction of protons to hydrogen, and nitrogenases, which reduce dinitrogen to ammonia. A specific focus is given to the different experimental parameters and strategies that are used to trap distinct enzyme states, specifically, oxidants, reductants, and gas treatments. Other themes presented here include the recent use of Cryo-EM, and how coupling various spectroscopies to crystallization is opening up new approaches for structural and mechanistic analysis.
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Affiliation(s)
- Jacob H Artz
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - Oleg A Zadvornyy
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - David W Mulder
- National Renewable Energy Laboratory, Biosciences Center, Golden, CO, United States
| | - Paul W King
- National Renewable Energy Laboratory, Biosciences Center, Golden, CO, United States
| | - John W Peters
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States.
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42
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Rodríguez-Maciá P, Reijerse E, Lubitz W, Birrell JA, Rüdiger O. Spectroscopic Evidence of Reversible Disassembly of the [FeFe] Hydrogenase Active Site. J Phys Chem Lett 2017; 8:3834-3839. [PMID: 28759237 DOI: 10.1021/acs.jpclett.7b01608] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
[FeFe] hydrogenases are extremely active and efficient H2-converting biocatalysts. Their active site comprises a unique [2Fe] subcluster bonded to a canonical [4Fe-4S] cluster. The [2Fe] subsite can be introduced into hydrogenases lacking an assembled H-cluster through incubation with a synthesized [2Fe]H precursor, which initially produces the CO-inhibited state of the enzyme. We present FTIR spectroelectrochemical studies on the CO-inhibited state of the [FeFe] hydrogenase from Desulfovibrio desulfuricans, DdHydAB. At very negative potentials, disassembly of the H-cluster and dissociation of the [2Fe] subcluster is observed. Subsequently raising the potential allows cofactor rebinding and H-cluster reassembly. This demonstrates how the stability of the [2Fe]-[4Fe-4S] intercluster bond depends on the applied potential and the presence of an inhibiting CO ligand on the [2Fe] subcluster. These results provide insight into the mechanisms of CO inhibition and H-cluster assembly in [FeFe] hydrogenases. A fundamental understanding of these properties will provide clues for designing better H2-converting catalysts.
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Affiliation(s)
- Patricia Rodríguez-Maciá
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Edward Reijerse
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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43
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Shepard EM, Byer AS, Aggarwal P, Betz JN, Scott AG, Shisler KA, Usselman RJ, Eaton GR, Eaton SS, Broderick JB. Electron Spin Relaxation and Biochemical Characterization of the Hydrogenase Maturase HydF: Insights into [2Fe-2S] and [4Fe-4S] Cluster Communication and Hydrogenase Activation. Biochemistry 2017; 56:3234-3247. [PMID: 28525271 PMCID: PMC5490485 DOI: 10.1021/acs.biochem.7b00169] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Nature utilizes [FeFe]-hydrogenase enzymes to catalyze the interconversion between H2 and protons and electrons. Catalysis occurs at the H-cluster, a carbon monoxide-, cyanide-, and dithiomethylamine-coordinated 2Fe subcluster bridged via a cysteine to a [4Fe-4S] cluster. Biosynthesis of this unique metallocofactor is accomplished by three maturase enzymes denoted HydE, HydF, and HydG. HydE and HydG belong to the radical S-adenosylmethionine superfamily of enzymes and synthesize the nonprotein ligands of the H-cluster. These enzymes interact with HydF, a GTPase that acts as a scaffold or carrier protein during 2Fe subcluster assembly. Prior characterization of HydF demonstrated the protein exists in both dimeric and tetrameric states and coordinates both [4Fe-4S]2+/+ and [2Fe-2S]2+/+ clusters [Shepard, E. M., Byer, A. S., Betz, J. N., Peters, J. W., and Broderick, J. B. (2016) Biochemistry 55, 3514-3527]. Herein, electron paramagnetic resonance (EPR) is utilized to characterize the [2Fe-2S]+ and [4Fe-4S]+ clusters bound to HydF. Examination of spin relaxation times using pulsed EPR in HydF samples exhibiting both [4Fe-4S]+ and [2Fe-2S]+ cluster EPR signals supports a model in which the two cluster types either are bound to widely separated sites on HydF or are not simultaneously bound to a single HydF species. Gel filtration chromatographic analyses of HydF spectroscopic samples strongly suggest the [2Fe-2S]+ and [4Fe-4S]+ clusters are coordinated to the dimeric form of the protein. Lastly, we examined the 2Fe subcluster-loaded form of HydF and showed the dimeric state is responsible for [FeFe]-hydrogenase activation. Together, the results indicate a specific role for the HydF dimer in the H-cluster biosynthesis pathway.
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Affiliation(s)
- Eric M Shepard
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Amanda S Byer
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Priyanka Aggarwal
- Department of Chemistry and Biochemistry, University of Denver , Denver, Colorado 80208, United States
| | - Jeremiah N Betz
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Anna G Scott
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Krista A Shisler
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Robert J Usselman
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Gareth R Eaton
- Department of Chemistry and Biochemistry, University of Denver , Denver, Colorado 80208, United States
| | - Sandra S Eaton
- Department of Chemistry and Biochemistry, University of Denver , Denver, Colorado 80208, United States
| | - Joan B Broderick
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
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Caserta G, Pecqueur L, Adamska-Venkatesh A, Papini C, Roy S, Artero V, Atta M, Reijerse E, Lubitz W, Fontecave M. Structural and functional characterization of the hydrogenase-maturation HydF protein. Nat Chem Biol 2017; 13:779-784. [DOI: 10.1038/nchembio.2385] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 03/06/2017] [Indexed: 11/09/2022]
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Galazzo L, Maso L, De Rosa E, Bortolus M, Doni D, Acquasaliente L, De Filippis V, Costantini P, Carbonera D. Identifying conformational changes with site-directed spin labeling reveals that the GTPase domain of HydF is a molecular switch. Sci Rep 2017; 7:1714. [PMID: 28490758 PMCID: PMC5431965 DOI: 10.1038/s41598-017-01886-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 04/05/2017] [Indexed: 11/17/2022] Open
Abstract
[FeFe]-hydrogenases catalyse the reduction of protons to hydrogen at a complex 2Fe[4Fe4S] center called H-cluster. The assembly of this active site is a multistep process involving three proteins, HydE, HydF and HydG. According to the current models, HydF has the key double role of scaffold, upon which the final H-cluster precursor is assembled, and carrier to transfer it to the target hydrogenase. The X-ray structure of HydF indicates that the protein is a homodimer with both monomers carrying two functional domains: a C-terminal FeS cluster-binding domain, where the precursor is assembled, and a N-terminal GTPase domain, whose exact contribution to cluster biogenesis and hydrogenase activation is still elusive. We previously obtained several hints suggesting that the binding of GTP to HydF could be involved in the interactions of this scaffold protein with the other maturases and with the hydrogenase itself. In this work, by means of site directed spin labeling coupled to EPR/PELDOR spectroscopy, we explored the conformational changes induced in a recombinant HydF protein by GTP binding, and provide the first clue that the HydF GTPase domain could be involved in the H-cluster assembly working as a molecular switch similarly to other known small GTPases.
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Affiliation(s)
- Laura Galazzo
- Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35131, Padova, Italy
| | - Lorenzo Maso
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy
| | - Edith De Rosa
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy
| | - Marco Bortolus
- Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35131, Padova, Italy
| | - Davide Doni
- Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35131, Padova, Italy
| | - Laura Acquasaliente
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via F. Marzolo 5, 35131, Padova, Italy
| | - Vincenzo De Filippis
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via F. Marzolo 5, 35131, Padova, Italy
| | - Paola Costantini
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy.
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35131, Padova, Italy.
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Li RX, Liu XF, Liu T, Yin YB, Zhou Y, Mei SK, Yan J. Electrocatalytic properties of [FeFe]-hydrogenases models and visible-light-driven hydrogen evolution efficiency promotion with porphyrin functionalized graphene nanocomposite. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.03.216] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Li Z, Xiao Z, Xu F, Zeng X, Liu X. Enhancement in catalytic proton reduction by an internal base in a diiron pentacarbonyl complex: its synthesis, characterisation, inter-conversion and electrochemical investigation. Dalton Trans 2017; 46:1864-1871. [DOI: 10.1039/c6dt04409c] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
An internal base bound to one of the diiron undergoes dissociation under a CO atmosphere and the freed base group as a proton relay enhances the catalysis of proton reduction.
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Affiliation(s)
- Zhimei Li
- School of Chemistry
- Nanchang University
- Nanchang 330031
- China
| | - Zhiyin Xiao
- College of Biological
- Chemical Sciences and Engineering
- Jiaxing University
- Jiaxing 314001
- China
| | - Fenfen Xu
- School of Chemistry
- Nanchang University
- Nanchang 330031
- China
| | - Xianghua Zeng
- College of Biological
- Chemical Sciences and Engineering
- Jiaxing University
- Jiaxing 314001
- China
| | - Xiaoming Liu
- College of Biological
- Chemical Sciences and Engineering
- Jiaxing University
- Jiaxing 314001
- China
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Megarity CF, Esselborn J, Hexter SV, Wittkamp F, Apfel UP, Happe T, Armstrong FA. Electrochemical Investigations of the Mechanism of Assembly of the Active-Site H-Cluster of [FeFe]-Hydrogenases. J Am Chem Soc 2016; 138:15227-15233. [PMID: 27776209 DOI: 10.1021/jacs.6b09366] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Protein film electrochemistry (PFE) has been used to study the assembly of the complex 6Fe active site of [FeFe]-hydrogenases (known as the H-cluster) from its precursors-the [4Fe-4S] domain that is already coordinated within the host, and the 2Fe domain that is presented as a synthetic water-soluble complex stabilized by an additional CO. Not only does PFE allow control of redox states via the electrode potential but also the immobilized state of the enzyme facilitates control of extremely low concentrations of the 2Fe complex. Results for two enzymes, CrHydA1 from Chlamydomonas reinhardtii and CpI from Clostridium pasteurianum, are very similar, despite large differences in size and structure. Assembly begins with very tight binding of the 34-valence electron 2Fe complex to the apo-[4Fe-4S] enzyme, well before the rate-determining step. The precursor is trapped under highly reducing conditions (<-0.5 V vs SHE) that prevent fusion of the [4Fe-4S] and 2Fe domains (via cysteine-S) since the immediate product would be too electron-rich. Relaxing this condition allows conversion to the active H-cluster. The intramolecular steps are relevant to the final stage of biological H-cluster maturation.
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Affiliation(s)
- Clare F Megarity
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford , South Parks Road, Oxford OX1 3QR, United Kingdom
| | | | - Suzannah V Hexter
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford , South Parks Road, Oxford OX1 3QR, United Kingdom
| | | | | | | | - Fraser A Armstrong
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford , South Parks Road, Oxford OX1 3QR, United Kingdom
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Birrell JA, Wrede K, Pawlak K, Rodriguez-Maciá P, Rüdiger O, Reijerse EJ, Lubitz W. Artificial Maturation of the Highly Active Heterodimeric [FeFe] Hydrogenase from Desulfovibrio desulfuricans
ATCC 7757. Isr J Chem 2016. [DOI: 10.1002/ijch.201600035] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- James A. Birrell
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Kathrin Wrede
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Krzysztof Pawlak
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Patricia Rodriguez-Maciá
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Edward J. Reijerse
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
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50
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Caserta G, Adamska-Venkatesh A, Pecqueur L, Atta M, Artero V, Roy S, Reijerse E, Lubitz W, Fontecave M. Chemical assembly of multiple metal cofactors: The heterologously expressed multidomain [FeFe]-hydrogenase from Megasphaera elsdenii. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1734-1740. [PMID: 27421233 DOI: 10.1016/j.bbabio.2016.07.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/03/2016] [Accepted: 07/10/2016] [Indexed: 10/21/2022]
Abstract
[FeFe]-hydrogenases are unique and fascinating enzymes catalyzing the reversible reduction of protons into hydrogen. These metalloenzymes display extremely large catalytic reaction rates at very low overpotential values and are, therefore, studied as potential catalysts for bioelectrodes of electrolyzers and fuel cells. Since they contain multiple metal cofactors whose biosynthesis depends on complex protein machineries, their preparation is difficult. As a consequence still few have been purified to homogeneity allowing spectroscopic and structural characterization. As part of a program aiming at getting easy access to new hydrogenases we report here a methodology based on a purely chemical assembly of their metal cofactors. This methodology is applied to the preparation and characterization of the hydrogenase from the fermentative anaerobic rumen bacterium Megasphaera elsdenii, which has only been incompletely characterized in the past.
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Affiliation(s)
- Giorgio Caserta
- Laboratoire de Chimie des Processus Biologiques, Collège de France, Université Pierre et Marie Curie, CNRS UMR 8229, 11 place Marcelin Berthelot, 75005 Paris, France
| | | | - Ludovic Pecqueur
- Laboratoire de Chimie des Processus Biologiques, Collège de France, Université Pierre et Marie Curie, CNRS UMR 8229, 11 place Marcelin Berthelot, 75005 Paris, France
| | - Mohamed Atta
- Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA/BIG, CNRS, 17 rue des martyrs, 38000 Grenoble, France
| | - Vincent Artero
- Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA/BIG, CNRS, 17 rue des martyrs, 38000 Grenoble, France
| | - Souvik Roy
- Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA/BIG, CNRS, 17 rue des martyrs, 38000 Grenoble, France
| | - Edward Reijerse
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Wolfgang Lubitz
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, Collège de France, Université Pierre et Marie Curie, CNRS UMR 8229, 11 place Marcelin Berthelot, 75005 Paris, France.
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