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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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Genome-Scale Mining of Acetogens of the Genus Clostridium Unveils Distinctive Traits in [FeFe]- and [NiFe]-Hydrogenase Content and Maturation. Microbiol Spectr 2022; 10:e0101922. [PMID: 35735976 PMCID: PMC9431212 DOI: 10.1128/spectrum.01019-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Knowledge of the organizational and functional properties of hydrogen metabolism is pivotal to the construction of a framework supportive of a hydrogen-fueled low-carbon economy. Hydrogen metabolism relies on the mechanism of action of hydrogenases. In this study, we investigated the genomes of several industrially relevant acetogens of the genus Clostridium (C. autoethanogenum, C. ljungdahlii, C. carboxidivorans, C. drakei, C. scatologenes, C. coskatii, C. ragsdalei, C. sp. AWRP) to systematically identify their intriguingly diversified hydrogenases’ repertoire. An entirely computational annotation pipeline unveiled common and strain-specific traits in the functional content of [NiFe]- and [FeFe]-hydrogenases. Hydrogenases were identified and categorized into functionally distinct classes by the combination of sequence homology, with respect to a database of curated nonredundant hydrogenases, with the analysis of sequence patterns characteristic of the mode of action of [FeFe]- and [NiFe]-hydrogenases. The inspection of the genes in the neighborhood of the catalytic subunits unveiled a wide agreement between their genomic arrangement and the gene organization templates previously developed for the predicted hydrogenase classes. Subunits’ characterization of the identified hydrogenases allowed us to glean some insights on the redox cofactor-binding determinants in the diaphorase subunits of the electron-bifurcating [FeFe]-hydrogenases. Finally, the reliability of the inferred hydrogenases was corroborated by the punctual analysis of the maturation proteins necessary for the biosynthesis of [NiFe]- and [FeFe]-hydrogenases. IMPORTANCE Mastering hydrogen metabolism can support a sustainable carbon-neutral economy. Of the many microorganisms metabolizing hydrogen, acetogens of the genus Clostridium are appealing, with some of them already in usage as industrial workhorses. Having provided detailed information on the hydrogenase content of an unprecedented number of clostridial acetogens at the gene level, our study represents a valuable knowledge base to deepen our understanding of hydrogenases’ functional specificity and/or redundancy and to develop a large array of biotechnological processes. We also believe our study could serve as a basis for future strain-engineering approaches, acting at the hydrogenases’ level or at the level of their maturation proteins. On the other side, the wealth of functional elements discussed in relation to the identified hydrogenases is worthy of further investigation by biochemical and structural studies to ultimately lead to the usage of these enzymes as valuable catalysts.
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Redman HJ, Huang P, Haumann M, Cheah MH, Berggren G. Lewis acid protection turns cyanide containing [FeFe]-hydrogenase mimics into proton reduction catalysts. Dalton Trans 2022; 51:4634-4643. [PMID: 35212328 PMCID: PMC8939051 DOI: 10.1039/d1dt03896f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Sustainable sources of hydrogen are a vital component of the envisioned energy transition. Understanding and mimicking the [FeFe]-hydrogenase provides a route to achieving this goal. In this study we re-visit a molecular mimic of the hydrogenase, the propyl dithiolate bridged complex [Fe2(μ-pdt)(CO)4(CN)2]2−, in which the cyanide ligands are tuned via Lewis acid interactions. This system provides a rare example of a cyanide containing [FeFe]-hydrogenase mimic capable of catalytic proton reduction, as demonstrated by cyclic voltammetry. EPR, FTIR, UV-vis and X-ray absorption spectroscopy are employed to characterize the species produced by protonation, and reduction or oxidation of the complex. The results reveal that biologically relevant iron-oxidation states can be generated, potentially including short-lived mixed valent Fe(i)Fe(ii) species. We propose that catalysis is initiated by protonation of the diiron complex and the resulting di-ferrous bridging hydride species can subsequently follow two different pathways to promote H2 gas formation depending on the applied reduction potential. Mimicking the hydrogen-bonding interactions of the [FeFe]-hydrogenase active-site using Lewis acids transforms an otherwise unstable cyanide containing hydrogenase mimic into a proton reduction catalyst.![]()
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Affiliation(s)
- Holly J Redman
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
| | - Ping Huang
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
| | - Michael Haumann
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Mun Hon Cheah
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
| | - Gustav Berggren
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
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4
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Smutná T, Dohnálková A, Sutak R, Narayanasamy RK, Tachezy J, Hrdý I. A cytosolic ferredoxin-independent hydrogenase possibly mediates hydrogen uptake in Trichomonas vaginalis. Curr Biol 2021; 32:124-135.e5. [PMID: 34762819 DOI: 10.1016/j.cub.2021.10.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/30/2021] [Accepted: 10/22/2021] [Indexed: 11/16/2022]
Abstract
Trichomonads, represented by the highly prevalent sexually transmitted human parasite Trichomonas vaginalis, are anaerobic eukaryotes with hydrogenosomes in the place of the standard mitochondria. Hydrogenosomes form indispensable FeS-clusters, synthesize ATP, and release molecular hydrogen as a waste product. Hydrogen formation is catalyzed by [FeFe] hydrogenase, the hallmark enzyme of all hydrogenosomes found in various eukaryotic anaerobes. Eukaryotic hydrogenases were originally thought to be exclusively localized within organelles, but today few eukaryotic anaerobes are known that possess hydrogenase in their cytosol. We identified a thus-far unknown hydrogenase in T. vaginalis cytosol that cannot use ferredoxin as a redox partner but can use cytochrome b5 as an electron acceptor. Trichomonads overexpressing the cytosolic hydrogenase, while maintaining the carbon flux through hydrogenosomes, show decreased excretion of hydrogen and increased excretion of methylated alcohols, suggesting that the cytosolic hydrogenase uses the hydrogen gas as a source of reducing power for the reactions occurring in the cytoplasm and thus accounts for the overall redox balance. This is the first evidence of hydrogen uptake in a eukaryote, although further work is needed to confirm it. Assembly of the catalytic center of [FeFe] hydrogenases (H-cluster) requires the activity of three dedicated maturases, and these proteins in T. vaginalis are exclusively localized in hydrogenosomes, where they participate in the maturation of organellar hydrogenases. Despite the different subcellular localization of cytosolic hydrogenase and maturases, the H-cluster is present in the cytosolic enzyme, suggesting the existence of an alternative mechanism of H-cluster assembly.
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Affiliation(s)
- Tamara Smutná
- Charles University, Faculty of Science, Department of Parasitology, BIOCEV, Vestec 252 50, Czech Republic
| | - Alena Dohnálková
- Charles University, Faculty of Science, Department of Parasitology, BIOCEV, Vestec 252 50, Czech Republic
| | - Róbert Sutak
- Charles University, Faculty of Science, Department of Parasitology, BIOCEV, Vestec 252 50, Czech Republic
| | - Ravi Kumar Narayanasamy
- Charles University, Faculty of Science, Department of Parasitology, BIOCEV, Vestec 252 50, Czech Republic
| | - Jan Tachezy
- Charles University, Faculty of Science, Department of Parasitology, BIOCEV, Vestec 252 50, Czech Republic
| | - Ivan Hrdý
- Charles University, Faculty of Science, Department of Parasitology, BIOCEV, Vestec 252 50, Czech Republic.
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5
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Espina G, Atalah J, Blamey JM. Extremophilic Oxidoreductases for the Industry: Five Successful Examples With Promising Projections. Front Bioeng Biotechnol 2021; 9:710035. [PMID: 34458243 PMCID: PMC8387880 DOI: 10.3389/fbioe.2021.710035] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 06/30/2021] [Indexed: 11/29/2022] Open
Abstract
In a global context where the development of more environmentally conscious technologies is an urgent need, the demand for enzymes for industrial processes is on the rise. Compared to conventional chemical catalysts, the implementation of biocatalysis presents important benefits including higher selectivity, increased sustainability, reduction in operating costs and low toxicity, which translate into cleaner production processes, lower environmental impact as well as increasing the safety of the operating staff. Most of the currently available commercial enzymes are of mesophilic origin, displaying optimal activity in narrow ranges of conditions, which limits their actual application under industrial settings. For this reason, enzymes from extremophilic microorganisms stand out for their specific characteristics, showing higher stability, activity and robustness than their mesophilic counterparts. Their unique structural adaptations allow them to resist denaturation at high temperatures and salinity, remain active at low temperatures, function at extremely acidic or alkaline pHs and high pressure, and participate in reactions in organic solvents and unconventional media. Because of the increased interest to replace chemical catalysts, the global enzymes market is continuously growing, with hydrolases being the most prominent type of enzymes, holding approximately two-third share, followed by oxidoreductases. The latter enzymes catalyze electron transfer reactions and are one of the most abundant classes of enzymes within cells. They hold a significant industrial potential, especially those from extremophiles, as their applications are multifold. In this article we aim to review the properties and potential applications of five different types of extremophilic oxidoreductases: laccases, hydrogenases, glutamate dehydrogenases (GDHs), catalases and superoxide dismutases (SODs). This selection is based on the extensive experience of our research group working with these particular enzymes, from the discovery up to the development of commercial products available for the research market.
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Affiliation(s)
| | | | - Jenny M. Blamey
- Fundación Biociencia, Santiago, Chile
- Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
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6
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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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7
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Li S, Chen W, Hu X, Feng F. Self-Assembly of Albumin and [FeFe]-Hydrogenase Mimics for Photocatalytic Hydrogen Evolution. ACS APPLIED BIO MATERIALS 2020; 3:2482-2488. [DOI: 10.1021/acsabm.0c00194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shuyi Li
- Key Laboratory of High Performance Polymer Material and Technology of Ministry of Education, Department of Polymer Science & Engineering, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Weijian Chen
- Key Laboratory of High Performance Polymer Material and Technology of Ministry of Education, Department of Polymer Science & Engineering, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Xiantao Hu
- Key Laboratory of High Performance Polymer Material and Technology of Ministry of Education, Department of Polymer Science & Engineering, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Fude Feng
- Key Laboratory of High Performance Polymer Material and Technology of Ministry of Education, Department of Polymer Science & Engineering, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
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8
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Muraki N, Ishii K, Uchiyama S, Itoh SG, Okumura H, Aono S. Structural characterization of HypX responsible for CO biosynthesis in the maturation of NiFe-hydrogenase. Commun Biol 2019; 2:385. [PMID: 31646188 PMCID: PMC6802093 DOI: 10.1038/s42003-019-0631-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 09/20/2019] [Indexed: 12/20/2022] Open
Abstract
Several accessory proteins are required for the assembly of the metal centers in hydrogenases. In NiFe-hydrogenases, CO and CN- are coordinated to the Fe in the NiFe dinuclear cluster of the active center. Though these diatomic ligands are biosynthesized enzymatically, detail mechanisms of their biosynthesis remain unclear. Here, we report the structural characterization of HypX responsible for CO biosynthesis to assemble the active site of NiFe hydrogenase. CoA is constitutionally bound in HypX. Structural characterization of HypX suggests that the formyl-group transfer will take place from N10-formyl-THF to CoA to form formyl-CoA in the N-terminal domain of HypX, followed by decarbonylation of formyl-CoA to produce CO in the C-terminal domain though the direct experimental results are not available yet. The conformation of CoA accommodated in the continuous cavity connecting the N- and C-terminal domains will interconvert between the extended and the folded conformations for HypX catalysis.
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Affiliation(s)
- Norifumi Muraki
- Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Department of Structural Molecular Science, The Graduate University for Advanced Studies, 38 Nishogo-naka, Myodaiji-cho, Okazaki 444-8585 Japan
| | - Kentaro Ishii
- Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
| | - Susumu Uchiyama
- Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Satoru G. Itoh
- Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Department of Structural Molecular Science, The Graduate University for Advanced Studies, 38 Nishogo-naka, Myodaiji-cho, Okazaki 444-8585 Japan
| | - Hisashi Okumura
- Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Department of Structural Molecular Science, The Graduate University for Advanced Studies, 38 Nishogo-naka, Myodaiji-cho, Okazaki 444-8585 Japan
| | - Shigetoshi Aono
- Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787 Japan
- Department of Structural Molecular Science, The Graduate University for Advanced Studies, 38 Nishogo-naka, Myodaiji-cho, Okazaki 444-8585 Japan
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9
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Ciofi-Baffoni S, Nasta V, Banci L. Protein networks in the maturation of human iron-sulfur proteins. Metallomics 2019; 10:49-72. [PMID: 29219157 DOI: 10.1039/c7mt00269f] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The biogenesis of iron-sulfur (Fe-S) proteins in humans is a multistage process occurring in different cellular compartments. The mitochondrial iron-sulfur cluster (ISC) assembly machinery composed of at least 17 proteins assembles mitochondrial Fe-S proteins. A cytosolic iron-sulfur assembly (CIA) machinery composed of at least 13 proteins has been more recently identified and shown to be responsible for the Fe-S cluster incorporation into cytosolic and nuclear Fe-S proteins. Cytosolic and nuclear Fe-S protein maturation requires not only the CIA machinery, but also the components of the mitochondrial ISC assembly machinery. An ISC export machinery, composed of a protein transporter located in the mitochondrial inner membrane, has been proposed to act in mediating the export process of a still unknown component that is required for the CIA machinery. Several functional and molecular aspects of the protein networks operative in the three machineries are still largely obscure. This Review focuses on the Fe-S protein maturation processes in humans with the specific aim of providing a molecular picture of the currently known protein-protein interaction networks. The human ISC and CIA machineries are presented, and the ISC export machinery is discussed with respect to possible molecules being the substrates of the mitochondrial protein transporter.
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Affiliation(s)
- Simone Ciofi-Baffoni
- Magnetic Resonance Center-CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy.
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10
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Bortolus M, Costantini P, Doni D, Carbonera D. Overview of the Maturation Machinery of the H-Cluster of [FeFe]-Hydrogenases with a Focus on HydF. Int J Mol Sci 2018; 19:E3118. [PMID: 30314343 PMCID: PMC6212873 DOI: 10.3390/ijms19103118] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/04/2018] [Accepted: 10/06/2018] [Indexed: 01/01/2023] Open
Abstract
Hydrogen production in nature is performed by hydrogenases. Among them, [FeFe]-hydrogenases have a peculiar active site, named H-cluster, that is made of two parts, synthesized in different pathways. The cubane sub-cluster requires the normal iron-sulfur cluster maturation machinery. The [2Fe] sub-cluster instead requires a dedicated set of maturase proteins, HydE, HydF, and HydG that work to assemble the cluster and deliver it to the apo-hydrogenase. In particular, the delivery is performed by HydF. In this review, we will perform an overview of the latest knowledge on the maturation machinery of the H-cluster, focusing in particular on HydF.
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Affiliation(s)
- Marco Bortolus
- Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35131 Padova, Italy.
| | - Paola Costantini
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131 Padova, Italy.
| | - Davide Doni
- 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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11
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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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12
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Wittkamp F, Senger M, Stripp ST, Apfel UP. [FeFe]-Hydrogenases: recent developments and future perspectives. Chem Commun (Camb) 2018; 54:5934-5942. [DOI: 10.1039/c8cc01275j] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
[FeFe]-Hydrogenases are the most efficient enzymes for catalytic hydrogen turnover.
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Affiliation(s)
- F. Wittkamp
- Faculty of Chemistry and Biochemistry
- Ruhr-Universität Bochum
- 44801 Bochum
- Germany
| | - M. Senger
- Department of Physics
- Freie Universität Berlin
- 1495 Berlin
- Germany
| | - S. T. Stripp
- Department of Physics
- Freie Universität Berlin
- 1495 Berlin
- Germany
| | - U.-P. Apfel
- Faculty of Chemistry and Biochemistry
- Ruhr-Universität Bochum
- 44801 Bochum
- Germany
- Fraunhofer UMSICHT
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13
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Meyer RL, Zhandosova AD, Biser TM, Heilweil EJ, Stromberg CJ. Photochemical Dynamics of a Trimethyl-Phosphine Derivatized [FeFe]-Hydrogenase Model Compound. Chem Phys 2018; 512. [PMID: 30983684 DOI: 10.1016/j.chemphys.2017.12.014] [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] [Indexed: 10/18/2022]
Abstract
Though there have been many studies on photosensitizers coupled to model complexes of the [FeFe]-hydrogenases, few have looked at how the models react upon exposure to light. To extract photoreaction information, ultrafast time-resolved UV/visible pump, IR probe spectroscopy was performed on Fe2(μ-S2C2H4)(CO)4(PMe3)2 (2b) dissolved in heptane and acetonitrile and the photochemical dynamics were determined. Excitation with 532 and 355 nm light produces bleaches and new absorptions that decay to half their original intensity with time constants of 300 ± 120 ps and 380 ± 210 ps in heptane and acetonitrile, respectively. These features persist to the microsecond timescale. The dynamics of 2b are assigned to formation of an initial set of photoproducts, which were a mixture of excited-state tricarbonyl isomers. These isomers decay into another set of long-lived photoproducts in which approximately half the excited-state tricarbonyl isomers recombine with CO to form another complex mixture of tricarbonyl and tetracarbonyl isomers.
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Affiliation(s)
- Rachel L Meyer
- Department of Chemistry and Physics, Hood College, 401 Rosemont Ave., Frederick, MD, 21701-8524, USA.,Department of Chemistry, University of Rochester, RC Box 270216, Rochester, NY 14627
| | - Annette D Zhandosova
- Department of Chemistry and Physics, Hood College, 401 Rosemont Ave., Frederick, MD, 21701-8524, USA.,Touro College of Osteopathic Medicine, 230 West 125 St., New York, NY 10027
| | - Tara M Biser
- Department of Chemistry and Physics, Hood College, 401 Rosemont Ave., Frederick, MD, 21701-8524, USA.,Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe St., Baltimore, MD 21205
| | - Edwin J Heilweil
- Radiation Physics Division, Physical Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899-8443, USA
| | - Christopher J Stromberg
- Department of Chemistry and Physics, Hood College, 401 Rosemont Ave., Frederick, MD, 21701-8524, USA
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14
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Bhattacharya P, Prokopchuk DE, Mock MT. Exploring the role of pendant amines in transition metal complexes for the reduction of N2 to hydrazine and ammonia. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.07.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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15
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Morra S, Valetti F, Gilardi G. [FeFe]-hydrogenases as biocatalysts in bio-hydrogen production. RENDICONTI LINCEI 2016. [DOI: 10.1007/s12210-016-0584-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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16
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Dinis P, Wieckowski BM, Roach PL. Metallocofactor assembly for [FeFe]-hydrogenases. Curr Opin Struct Biol 2016; 41:90-97. [PMID: 27344601 DOI: 10.1016/j.sbi.2016.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 06/05/2016] [Accepted: 06/06/2016] [Indexed: 11/27/2022]
Abstract
Hydrogenases are a potential source of environmentally benign bioenergy, using complex cofactors to catalyze the reversible reduction of protons to form hydrogen. The most active subclass, the [FeFe]-hydrogenases, is dependent on a metallocofactor, the H cluster, that consists of a two iron subcluster ([2Fe]H) bridging to a classical cubane cluster ([4Fe-4S]H). The ligands coordinating to the diiron subcluster include an azadithiolate, three carbon monoxides, and two cyanides. To assemble this complex cofactor, three maturase enzymes, HydG, HydE and HydF are required. The biosynthesis of the diatomic ligands proceeds by an unusual fragmentation mechanism, and structural studies in combination with spectroscopic analysis have started to provide insights into the HydG mediated assembly of a [2Fe]H subcluster precursor.
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Affiliation(s)
- Pedro Dinis
- Chemistry and the Institute for Life Sciences, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK
| | - Beata M Wieckowski
- Chemistry and the Institute for Life Sciences, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK
| | - Peter L Roach
- Chemistry and the Institute for Life Sciences, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK.
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17
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Rohac R, Amara P, Benjdia A, Martin L, Ruffié P, Favier A, Berteau O, Mouesca JM, Fontecilla-Camps JC, Nicolet Y. Carbon–sulfur bond-forming reaction catalysed by the radical SAM enzyme HydE. Nat Chem 2016; 8:491-500. [DOI: 10.1038/nchem.2490] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 02/25/2016] [Indexed: 11/09/2022]
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18
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Sicoli G, Mouesca JM, Zeppieri L, Amara P, Martin L, Barra AL, Fontecilla-Camps JC, Gambarelli S, Nicolet Y. Fine-tuning of a radical-based reaction by radical S-adenosyl-L-methionine tryptophan lyase. Science 2016; 351:1320-3. [DOI: 10.1126/science.aad8995] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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19
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Wang F, Wen M, Feng K, Liang WJ, Li XB, Chen B, Tung CH, Wu LZ. Amphiphilic polymeric micelles as microreactors: improving the photocatalytic hydrogen production of the [FeFe]-hydrogenase mimic in water. Chem Commun (Camb) 2016; 52:457-60. [DOI: 10.1039/c5cc07499a] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An amphiphilic polymeric micelle is utilized as a microreactor to load a hydrophobic [FeFe]-hydrogenase mimic for photocatalytic hydrogen production in water.
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Affiliation(s)
- Feng Wang
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Min Wen
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Ke Feng
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Wen-Jing Liang
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Xu-Bing Li
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Bin Chen
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Chen-Ho Tung
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
| | - Li-Zhu Wu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials
- Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences
- The Chinese Academy of Sciences
- Beijing 100190
- P. R. China
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20
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CO and CN- syntheses by [FeFe]-hydrogenase maturase HydG are catalytically differentiated events. Proc Natl Acad Sci U S A 2015; 113:104-9. [PMID: 26699472 DOI: 10.1073/pnas.1515842113] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The synthesis and assembly of the active site [FeFe] unit of [FeFe]-hydrogenases require at least three maturases. The radical S-adenosyl-l-methionine HydG, the best characterized of these proteins, is responsible for the synthesis of the hydrogenase CO and CN(-) ligands from tyrosine-derived dehydroglycine (DHG). We speculated that CN(-) and the CO precursor (-):CO2H may be generated through an elimination reaction. We tested this hypothesis with both wild type and HydG variants defective in second iron-sulfur cluster coordination by measuring the in vitro production of CO, CN(-), and (-):CO2H-derived formate. We indeed observed formate production under these conditions. We conclude that HydG is a multifunctional enzyme that produces DHG, CN(-), and CO at three well-differentiated catalytic sites. We also speculate that homocysteine, cysteine, or a related ligand could be involved in Fe(CO)x(CN)y transfer to the HydF carrier/scaffold.
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21
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Raugei S, Helm ML, Hammes-Schiffer S, Appel AM, O’Hagan M, Wiedner ES, Bullock RM. Experimental and Computational Mechanistic Studies Guiding the Rational Design of Molecular Electrocatalysts for Production and Oxidation of Hydrogen. Inorg Chem 2015; 55:445-60. [DOI: 10.1021/acs.inorgchem.5b02262] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Simone Raugei
- Center for Molecular Electrocatalysis,
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, K2−12, Richland, Washington 99352, United States
| | - Monte L. Helm
- Center for Molecular Electrocatalysis,
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, K2−12, Richland, Washington 99352, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, University of Illinois at Urbana—Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Aaron M. Appel
- Center for Molecular Electrocatalysis,
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, K2−12, Richland, Washington 99352, United States
| | - Molly O’Hagan
- Center for Molecular Electrocatalysis,
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, K2−12, Richland, Washington 99352, United States
| | - Eric S. Wiedner
- Center for Molecular Electrocatalysis,
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, K2−12, Richland, Washington 99352, United States
| | - R. Morris Bullock
- Center for Molecular Electrocatalysis,
Physical Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, K2−12, Richland, Washington 99352, United States
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22
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Morra S, Maurelli S, Chiesa M, Mulder DW, Ratzloff MW, Giamello E, King PW, Gilardi G, Valetti F. The effect of a C298D mutation in CaHydA [FeFe]-hydrogenase: Insights into the protein-metal cluster interaction by EPR and FTIR spectroscopic investigation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:98-106. [PMID: 26482707 DOI: 10.1016/j.bbabio.2015.10.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 10/01/2015] [Accepted: 10/15/2015] [Indexed: 01/17/2023]
Abstract
A conserved cysteine located in the signature motif of the catalytic center (H-cluster) of [FeFe]-hydrogenases functions in proton transfer. This residue corresponds to C298 in Clostridium acetobutylicum CaHydA. Despite the chemical and structural difference, the mutant C298D retains fast catalytic activity, while replacement with any other amino acid causes significant activity loss. Given the proximity of C298 to the H-cluster, the effect of the C298D mutation on the catalytic center was studied by continuous wave (CW) and pulse electron paramagnetic resonance (EPR) and by Fourier transform infrared (FTIR) spectroscopies. Comparison of the C298D mutant with the wild type CaHydA by CW and pulse EPR showed that the electronic structure of the center is not altered. FTIR spectroscopy confirmed that absorption peak values observed in the mutant are virtually identical to those observed in the wild type, indicating that the H-cluster is not generally affected by the mutation. Significant differences were observed only in the inhibited state Hox-CO: the vibrational modes assigned to the COexo and Fed-CO in this state are shifted to lower values in C298D, suggesting different interaction of these ligands with the protein moiety when C298 is changed to D298. More relevant to the catalytic cycle, the redox equilibrium between the Hox and Hred states is modified by the mutation, causing a prevalence of the oxidized state. This work highlights how the interactions between the protein environment and the H-cluster, a dynamic closely interconnected system, can be engineered and studied in the perspective of designing bio-inspired catalysts and mimics.
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Affiliation(s)
- Simone Morra
- Department of Life Sciences and Systems Biology, University of Torino, Torino 10133, Italy
| | - Sara Maurelli
- Department of Chemistry, University of Torino, Torino 10133, Italy
| | - Mario Chiesa
- Department of Chemistry, University of Torino, Torino 10133, Italy
| | - David W Mulder
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Michael W Ratzloff
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Elio Giamello
- Department of Chemistry, University of Torino, Torino 10133, Italy
| | - Paul W King
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Gianfranco Gilardi
- Department of Life Sciences and Systems Biology, University of Torino, Torino 10133, Italy
| | - Francesca Valetti
- Department of Life Sciences and Systems Biology, University of Torino, Torino 10133, Italy.
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23
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Cysteine as a ligand platform in the biosynthesis of the FeFe hydrogenase H cluster. Proc Natl Acad Sci U S A 2015; 112:11455-60. [PMID: 26324916 DOI: 10.1073/pnas.1508440112] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Hydrogenases catalyze the redox interconversion of protons and H2, an important reaction for a number of metabolic processes and for solar fuel production. In FeFe hydrogenases, catalysis occurs at the H cluster, a metallocofactor comprising a [4Fe-4S]H subcluster coupled to a [2Fe]H subcluster bound by CO, CN(-), and azadithiolate ligands. The [2Fe]H subcluster is assembled by the maturases HydE, HydF, and HydG. HydG is a member of the radical S-adenosyl-L-methionine family of enzymes that transforms Fe and L-tyrosine into an [Fe(CO)2(CN)] synthon that is incorporated into the H cluster. Although it is thought that the site of synthon formation in HydG is the "dangler" Fe of a [5Fe] cluster, many mechanistic aspects of this chemistry remain unresolved including the full ligand set of the synthon, how the dangler Fe initially binds to HydG, and how the synthon is released at the end of the reaction. To address these questions, we herein show that L-cysteine (Cys) binds the auxiliary [4Fe-4S] cluster of HydG and further chelates the dangler Fe. We also demonstrate that a [4Fe-4S]aux[CN] species is generated during HydG catalysis, a process that entails the loss of Cys and the [Fe(CO)2(CN)] fragment; on this basis, we suggest that Cys likely completes the coordination sphere of the synthon. Thus, through spectroscopic analysis of HydG before and after the synthon is formed, we conclude that Cys serves as the ligand platform on which the synthon is built and plays a role in both Fe(2+) binding and synthon release.
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24
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Darmon JM, Kumar N, Hulley EB, Weiss CJ, Raugei S, Bullock RM, Helm ML. Increasing the rate of hydrogen oxidation without increasing the overpotential: a bio-inspired iron molecular electrocatalyst with an outer coordination sphere proton relay. Chem Sci 2015; 6:2737-2745. [PMID: 29142678 PMCID: PMC5654417 DOI: 10.1039/c5sc00398a] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 03/04/2015] [Indexed: 02/04/2023] Open
Abstract
Oxidation of hydrogen (H2) to protons and electrons for energy production in fuel cells is currently catalyzed by platinum, but its low abundance and high cost present drawbacks to widespread adoption. Precisely controlled proton removal from the active site is critical in hydrogenase enzymes in nature that catalyze H2 oxidation using earth-abundant metals (iron and nickel). Here we report a synthetic iron complex, (CpC5F4N)Fe(PEtN(CH2)3NMe2 PEt)(Cl), that serves as a precatalyst for the oxidation of H2, with turnover frequencies of 290 s-1 in fluorobenzene, under 1 atm of H2 using 1,4-diazabicyclo[2.2.2]octane (DABCO) as the exogenous base. The inclusion of a properly tuned outer coordination sphere proton relay results in a cooperative effect between the primary, secondary and outer coordination spheres for moving protons, increasing the rate of H2 oxidation without increasing the overpotential when compared with the analogous complex featuring a single pendant base. This finding emphasizes the key role of pendant amines in mimicking the functionality of the proton pathway in the hydrogenase enzymes.
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Affiliation(s)
- Jonathan M Darmon
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
| | - Neeraj Kumar
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
| | - Elliott B Hulley
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
| | - Charles J Weiss
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
| | - Simone Raugei
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
| | - R Morris Bullock
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
| | - Monte L Helm
- Center for Molecular Electrocatalysis , Physical Sciences Division , Pacific Northwest National Laboratory , P.O. Box 999, K2-57 , Richland , Washington 99352 , USA .
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25
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Betz JN, Boswell NW, Fugate CJ, Holliday GL, Akiva E, Scott AG, Babbitt PC, Peters JW, Shepard EM, Broderick JB. [FeFe]-hydrogenase maturation: insights into the role HydE plays in dithiomethylamine biosynthesis. Biochemistry 2015; 54:1807-18. [PMID: 25654171 DOI: 10.1021/bi501205e] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
HydE and HydG are radical S-adenosyl-l-methionine enzymes required for the maturation of [FeFe]-hydrogenase (HydA) and produce the nonprotein organic ligands characteristic of its unique catalytic cluster. The catalytic cluster of HydA (the H-cluster) is a typical [4Fe-4S] cubane bridged to a 2Fe-subcluster that contains two carbon monoxides, three cyanides, and a bridging dithiomethylamine as ligands. While recent studies have shed light on the nature of diatomic ligand biosynthesis by HydG, little information exists on the function of HydE. Herein, we present biochemical, spectroscopic, bioinformatic, and molecular modeling data that together map the active site and provide significant insight into the role of HydE in H-cluster biosynthesis. Electron paramagnetic resonance and UV-visible spectroscopic studies demonstrate that reconstituted HydE binds two [4Fe-4S] clusters and copurifies with S-adenosyl-l-methionine. Incorporation of deuterium from D2O into 5'-deoxyadenosine, the cleavage product of S-adenosyl-l-methionine, coupled with molecular docking experiments suggests that the HydE substrate contains a thiol functional group. This information, along with HydE sequence similarity and genome context networks, has allowed us to redefine the presumed mechanism for HydE away from BioB-like sulfur insertion chemistry; these data collectively suggest that the source of the sulfur atoms in the dithiomethylamine bridge of the H-cluster is likely derived from HydE's thiol containing substrate.
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Affiliation(s)
- Jeremiah N Betz
- Department of Chemistry & Biochemistry, Montana State University , Bozeman, Montana 59717, United States
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26
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Tsaousis AD, Nyvltová E, Sutak R, Hrdy I, Tachezy J. A nonmitochondrial hydrogen production in Naegleria gruberi. Genome Biol Evol 2015; 6:792-9. [PMID: 24682152 PMCID: PMC4007538 DOI: 10.1093/gbe/evu065] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Naegleria gruberi is a free-living heterotrophic aerobic amoeba well known for its ability to transform from an amoeba to a flagellate form. The genome of N. gruberi has been recently published, and in silico predictions demonstrated that Naegleria has the capacity for both aerobic respiration and anaerobic biochemistry to produce molecular hydrogen in its mitochondria. This finding was considered to have fundamental implications on the evolution of mitochondrial metabolism and of the last eukaryotic common ancestor. However, no actual experimental data have been shown to support this hypothesis. For this reason, we have decided to investigate the anaerobic metabolism of the mitochondrion of N. gruberi. Using in vivo biochemical assays, we have demonstrated that N. gruberi has indeed a functional [FeFe]-hydrogenase, an enzyme that is attributed to anaerobic organisms. Surprisingly, in contrast to the published predictions, we have demonstrated that hydrogenase is localized exclusively in the cytosol, while no hydrogenase activity was associated with mitochondria of the organism. In addition, cytosolic localization displayed for HydE, a marker component of hydrogenase maturases. Naegleria gruberi, an obligate aerobic organism and one of the earliest eukaryotes, is producing hydrogen, a function that raises questions on the purpose of this pathway for the lifestyle of the organism and potentially on the evolution of eukaryotes.
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Affiliation(s)
- Anastasios D Tsaousis
- Department of Parasitology, Faculty of Science, Charles University in Prague, Czech Republic
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27
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Paul VD, Lill R. Biogenesis of cytosolic and nuclear iron-sulfur proteins and their role in genome stability. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1528-39. [PMID: 25583461 DOI: 10.1016/j.bbamcr.2014.12.018] [Citation(s) in RCA: 170] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 12/08/2014] [Accepted: 12/12/2014] [Indexed: 01/09/2023]
Abstract
Iron-sulfur (Fe-S) clusters are versatile protein cofactors that require numerous components for their synthesis and insertion into apoproteins. In eukaryotes, maturation of cytosolic and nuclear Fe-S proteins is accomplished by cooperation of the mitochondrial iron-sulfur cluster (ISC) assembly and export machineries, and the cytosolic iron-sulfur protein assembly (CIA) system. Currently, nine CIA proteins are known to specifically assist the two major steps of the biogenesis reaction. They are essential for cell viability and conserved from yeast to man. The essential character of this biosynthetic process is explained by the involvement of Fe-S proteins in central processes of life, e.g., protein translation and numerous steps of nuclear DNA metabolism such as DNA replication and repair. Malfunctioning of these latter Fe-S enzymes leads to genome instability, a hallmark of cancer. This review is focused on the maturation and biological function of cytosolic and nuclear Fe-S proteins, a topic of central interest for both basic and medical research. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
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Affiliation(s)
- Viktoria Désirée Paul
- Institut für Zytobiologie und Zytopathologie, Philipps-Universität Marburg, Robert-Koch-Straße 6, 35032 Marburg, Germany
| | - Roland Lill
- Institut für Zytobiologie und Zytopathologie, Philipps-Universität Marburg, Robert-Koch-Straße 6, 35032 Marburg, Germany; LOEWE Zentrum für Synthetische Mikrobiologie SynMikro, Hans-Meerwein-Str., 35043 Marburg, Germany.
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28
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Byer AS, Shepard EM, Peters JW, Broderick JB. Radical S-adenosyl-L-methionine chemistry in the synthesis of hydrogenase and nitrogenase metal cofactors. J Biol Chem 2014; 290:3987-94. [PMID: 25477518 DOI: 10.1074/jbc.r114.578161] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nitrogenase, [FeFe]-hydrogenase, and [Fe]-hydrogenase enzymes perform catalysis at metal cofactors with biologically unusual non-protein ligands. The FeMo cofactor of nitrogenase has a MoFe7S9 cluster with a central carbon, whereas the H-cluster of [FeFe]-hydrogenase contains a 2Fe subcluster coordinated by cyanide and CO ligands as well as dithiomethylamine; the [Fe]-hydrogenase cofactor has CO and guanylylpyridinol ligands at a mononuclear iron site. Intriguingly, radical S-adenosyl-L-methionine enzymes are vital for the assembly of all three of these diverse cofactors. This minireview presents and discusses the current state of knowledge of the radical S-adenosylmethionine enzymes required for synthesis of these remarkable metal cofactors.
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Affiliation(s)
- Amanda S Byer
- From the Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717
| | - Eric M Shepard
- From the Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717
| | - John W Peters
- From the Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717
| | - Joan B Broderick
- From the Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717
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29
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Shepard EM, Mus F, Betz JN, Byer AS, Duffus BR, Peters JW, Broderick JB. [FeFe]-hydrogenase maturation. Biochemistry 2014; 53:4090-104. [PMID: 24878200 DOI: 10.1021/bi500210x] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Hydrogenases are metalloenzymes that catalyze the reversible reduction of protons at unusual metal centers. This Current Topic discusses recent advances in elucidating the steps involved in the biosynthesis of the complex metal cluster at the [FeFe]-hydrogenase (HydA) active site, known as the H-cluster. The H-cluster is composed of a 2Fe subcluster that is anchored within the active site by a bridging cysteine thiolate to a [4Fe-4S] cubane. The 2Fe subcluster contains carbon monoxide, cyanide, and bridging dithiolate ligands. H-cluster biosynthesis is now understood to occur stepwise; standard iron-sulfur cluster assembly machinery builds the [4Fe-4S] cubane of the H-cluster, while three specific maturase enzymes known as HydE, HydF, and HydG assemble the 2Fe subcluster. HydE and HydG are both radical S-adenosylmethionine enzymes that interact with an iron-sulfur cluster binding GTPase scaffold, HydF, during the construction of the 2Fe subcluster moiety. In an unprecedented biochemical reaction, HydG cleaves tyrosine and decomposes the resulting dehydroglycine into carbon monoxide and cyanide ligands. The role of HydE in the biosynthetic pathway remains undefined, although it is hypothesized to be critical for the synthesis of the bridging dithiolate. HydF is the site where the complete 2Fe subcluster is formed and ultimately delivered to the immature hydrogenase protein in the final step of [FeFe]-hydrogenase maturation. This work addresses the roles of and interactions among HydE, HydF, HydG, and HydA in the formation of the mature [FeFe]-hydrogenase.
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Affiliation(s)
- Eric M Shepard
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
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30
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Broderick JB, Duffus B, Duschene KS, Shepard EM. Radical S-adenosylmethionine enzymes. Chem Rev 2014; 114:4229-317. [PMID: 24476342 PMCID: PMC4002137 DOI: 10.1021/cr4004709] [Citation(s) in RCA: 584] [Impact Index Per Article: 58.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Joan B. Broderick
- Department of Chemistry and
Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Benjamin
R. Duffus
- Department of Chemistry and
Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Kaitlin S. Duschene
- Department of Chemistry and
Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Eric M. Shepard
- Department of Chemistry and
Biochemistry, Montana State University, Bozeman, Montana 59717, United States
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31
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Happe T, Hemschemeier A. Metalloprotein mimics – old tools in a new light. Trends Biotechnol 2014; 32:170-6. [DOI: 10.1016/j.tibtech.2014.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 02/07/2014] [Accepted: 02/07/2014] [Indexed: 01/03/2023]
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32
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Affiliation(s)
- Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Hideaki Ogata
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Edward Reijerse
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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33
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Morris RH. Estimating the Acidity of Transition Metal Hydride and Dihydrogen Complexes by Adding Ligand Acidity Constants. J Am Chem Soc 2014; 136:1948-59. [DOI: 10.1021/ja410718r] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Robert H. Morris
- Department of Chemistry, University of Toronto, 80 Saint
George Street, Toronto, Ontario M5S 3H6, Canada
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34
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Engineering Hydrogenases for H2 Production: Bolts and Goals. MICROBIAL BIOENERGY: HYDROGEN PRODUCTION 2014. [DOI: 10.1007/978-94-017-8554-9_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Bullock RM, Appel AM, Helm ML. Production of hydrogen by electrocatalysis: making the H–H bond by combining protons and hydrides. Chem Commun (Camb) 2014; 50:3125-43. [DOI: 10.1039/c3cc46135a] [Citation(s) in RCA: 213] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Electrocatalytic production of hydrogen by nickel complexes is reviewed, with an emphasis on heterocoupling of protons and hydrides.
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Affiliation(s)
- R. Morris Bullock
- Center for Molecular Electrocatalysis (efrc.pnnl.gov)
- Physical Sciences Division
- Pacific Northwest National Laboratory
- , USA
| | - Aaron M. Appel
- Center for Molecular Electrocatalysis (efrc.pnnl.gov)
- Physical Sciences Division
- Pacific Northwest National Laboratory
- , USA
| | - Monte L. Helm
- Center for Molecular Electrocatalysis (efrc.pnnl.gov)
- Physical Sciences Division
- Pacific Northwest National Laboratory
- , USA
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36
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Netz DJA, Mascarenhas J, Stehling O, Pierik AJ, Lill R. Maturation of cytosolic and nuclear iron-sulfur proteins. Trends Cell Biol 2013; 24:303-12. [PMID: 24314740 DOI: 10.1016/j.tcb.2013.11.005] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 11/25/2022]
Abstract
Eukaryotic cells contain numerous cytosolic and nuclear iron-sulfur (Fe/S) proteins that perform key functions in metabolic catalysis, iron regulation, protein translation, DNA synthesis, and DNA repair. Synthesis of Fe/S clusters and their insertion into apoproteins are essential for viability and are conserved in eukaryotes. The process is catalyzed in two major steps by the CIA (cytosolic iron-sulfur protein assembly) machinery encompassing nine known proteins. First, a [4Fe-4S] cluster is assembled on a scaffold complex. This step requires a sulfur-containing compound from mitochondria and reducing equivalents from an electron transfer chain. Second, the Fe/S cluster is transferred from the scaffold to specific apoproteins by the CIA targeting complex. This review summarizes our molecular knowledge on CIA protein function during the assembly process.
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Affiliation(s)
- Daili J A Netz
- Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Strasse 6, 35032 Marburg, Germany
| | - Judita Mascarenhas
- Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Strasse 6, 35032 Marburg, Germany
| | - Oliver Stehling
- Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Strasse 6, 35032 Marburg, Germany
| | - Antonio J Pierik
- Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Strasse 6, 35032 Marburg, Germany
| | - Roland Lill
- Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Strasse 6, 35032 Marburg, Germany; Max-Planck-Institut für Terrestrische Mikrobiologie, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany; LOEWE (Landes-Offensive zur Entwicklung Wissenschaftlich-Ökonomischer Exzellenz) Zentrum für Synthetische Mikrobiologie (SynMikro), Hans-Meerwein-Strasse, 35043 Marburg, Germany.
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37
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Jian JX, Liu Q, Li ZJ, Wang F, Li XB, Li CB, Liu B, Meng QY, Chen B, Feng K, Tung CH, Wu LZ. Chitosan confinement enhances hydrogen photogeneration from a mimic of the diiron subsite of [FeFe]-hydrogenase. Nat Commun 2013; 4:2695. [DOI: 10.1038/ncomms3695] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 10/01/2013] [Indexed: 01/01/2023] Open
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Kuchenreuther JM, Myers WK, Stich TA, George SJ, NejatyJahromy Y, Swartz JR, Britt RD. A Radical Intermediate in Tyrosine Scission to the CO and CN- Ligands of FeFe Hydrogenase. Science 2013; 342:472-5. [DOI: 10.1126/science.1241859] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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McCullagh M, Voth GA. Unraveling the Role of the Protein Environment for [FeFe]-Hydrogenase: A New Application of Coarse-Graining. J Phys Chem B 2013; 117:4062-71. [DOI: 10.1021/jp402441s] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Martin McCullagh
- Department of Chemistry,
James Franck Institute, Institute
for Biophysical Dynamics, and Computation Institute, The University of Chicago, Chicago, Illinois 60637,
United States
| | - Gregory A. Voth
- Department of Chemistry,
James Franck Institute, Institute
for Biophysical Dynamics, and Computation Institute, The University of Chicago, Chicago, Illinois 60637,
United States
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40
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Winkler M, Esselborn J, Happe T. Molecular basis of [FeFe]-hydrogenase function: an insight into the complex interplay between protein and catalytic cofactor. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:974-85. [PMID: 23507618 DOI: 10.1016/j.bbabio.2013.03.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 02/21/2013] [Accepted: 03/08/2013] [Indexed: 12/20/2022]
Abstract
The precise electrochemical features of metal cofactors that convey the functions of redox enzymes are essentially determined by the specific interaction pattern between cofactor and enclosing protein environment. However, while biophysical techniques allow a detailed understanding of the features characterizing the cofactor itself, knowledge about the contribution of the protein part is much harder to obtain. [FeFe]-hydrogenases are an interesting class of enzymes that catalyze both, H2 oxidation and the reduction of protons to molecular hydrogen with significant efficiency. The active site of these proteins consists of an unusual prosthetic group (H-cluster) with six iron and six sulfur atoms. While H-cluster architecture and catalytic states during the different steps of H2 turnover have been thoroughly investigated during the last 20 years, possible functional contributions from the polypeptide framework were only assumed according to the level of conservancy and X-ray structure analyses. Due to the recent development of simpler and more efficient expression systems the role of single amino acids can now be experimentally investigated. This article summarizes, compares and categorizes the results of recent investigations based on site directed and random mutagenesis according to their informative value about structure function relationships in [FeFe]-hydrogenases. This article is part of a Special Issue entitled: Metals in Bioenergetics and Biomimetics Systems.
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Affiliation(s)
- Martin Winkler
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, Bochum, Germany
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41
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Expression of Shewanella oneidensis MR-1 [FeFe]-hydrogenase genes in Anabaena sp. strain PCC 7120. Appl Environ Microbiol 2012; 78:8579-86. [PMID: 23023750 DOI: 10.1128/aem.01959-12] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
H(2) generated from renewable resources holds promise as an environmentally innocuous fuel that releases only energy and water when consumed. In biotechnology, photoautotrophic oxygenic diazotrophs could produce H(2) from water and sunlight using the cells' endogenous nitrogenases. However, nitrogenases have low turnover numbers and require large amounts of ATP. [FeFe]-hydrogenases found in other organisms can have 1,000-fold higher turnover numbers and no specific requirement for ATP but are very O(2) sensitive. Certain filamentous cyanobacteria protect nitrogenase from O(2) by sequestering the enzyme within internally micro-oxic, differentiated cells called heterocysts. We heterologously expressed the [FeFe]-hydrogenase operon from Shewanella oneidensis MR-1 in Anabaena sp. strain PCC 7120 using the heterocyst-specific promoter P(hetN). Active [FeFe]-hydrogenase was detected in and could be purified from aerobically grown Anabaena sp. strain PCC 7120, but only when the organism was grown under nitrate-depleted conditions that elicited heterocyst formation. These results suggest that the heterocysts protected the [FeFe]-hydrogenase against inactivation by O(2).
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The [4Fe-4S]-cluster coordination of [FeFe]-hydrogenase maturation protein HydF as revealed by EPR and HYSCORE spectroscopies. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:2149-57. [PMID: 22985598 DOI: 10.1016/j.bbabio.2012.09.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/31/2012] [Accepted: 09/07/2012] [Indexed: 11/23/2022]
Abstract
[FeFe] hydrogenases are key enzymes for bio(photo)production of molecular hydrogen, and several efforts are underway to understand how their complex active site is assembled. This site contains a [4Fe-4S]-2Fe cluster and three conserved maturation proteins are required for its biosynthesis. Among them, HydF has a double task of scaffold, in which the dinuclear iron precursor is chemically modified by the two other maturases, and carrier to transfer this unit to a hydrogenase containing a preformed [4Fe-4S]-cluster. This dual role is associated with the capability of HydF to bind and dissociate an iron-sulfur center, due to the presence of the conserved FeS-cluster binding sequence CxHx(46-53)HCxxC. The recently solved three-dimensional structure of HydF from Thermotoga neapolitana described the domain containing the three cysteines which are supposed to bind the FeS cluster, and identified the position of two conserved histidines which could provide the fourth iron ligand. The functional role of two of these cysteines in the activation of [FeFe]-hydrogenases has been confirmed by site-specific mutagenesis. On the other hand, the contribution of the three cysteines to the FeS cluster coordination sphere is still to be demonstrated. Furthermore, the potential role of the two histidines in [FeFe]-hydrogenase maturation has never been addressed, and their involvement as fourth ligand for the cluster coordination is controversial. In this work we combined site-specific mutagenesis with EPR (electron paramagnetic resonance) and HYSCORE (hyperfine sublevel correlation spectroscopy) to assign a role to these conserved residues, in both cluster coordination and hydrogenase maturation/activation, in HydF proteins from different microorganisms.
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Vallese F, Berto P, Ruzzene M, Cendron L, Sarno S, De Rosa E, Giacometti GM, Costantini P. Biochemical analysis of the interactions between the proteins involved in the [FeFe]-hydrogenase maturation process. J Biol Chem 2012; 287:36544-55. [PMID: 22932901 DOI: 10.1074/jbc.m112.388900] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
[FeFe]-hydrogenases are iron-sulfur proteins characterized by a complex active site, the H-cluster, whose assembly requires three conserved maturases. HydE and HydG are radical S-adenosylmethionine enzymes that chemically modify a H-cluster precursor on HydF, a GTPase with a dual role of scaffold on which this precursor is synthesized, and carrier to transfer it to the hydrogenase. Coordinate structural and functional relationships between HydF and the two other maturases are crucial for the H-cluster assembly. However, to date only qualitative analysis of this protein network have been provided. In this work we showed that the interactions of HydE and HydG with HydF are distinct events, likely occurring in a precise functional order driven by different kinetic properties, independently of the HydF GTPase activity, which is instead involved in the dissociation of the maturases from the scaffold. We also found that HydF is able to interact with the hydrogenase only when co-expressed with the two other maturases, indicating that under these conditions it harbors per se all the structural elements needed to transfer the H-cluster precursor, thus completing the maturation process. These results open new working perspectives aimed at improving the knowledge of how these complex metalloenzymes are biosynthesized.
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Affiliation(s)
- Francesca Vallese
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131 Padua, Italy
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