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Clowez S, Godaux D, Cardol P, Wollman FA, Rappaport F. The involvement of hydrogen-producing and ATP-dependent NADPH-consuming pathways in setting the redox poise in the chloroplast of Chlamydomonas reinhardtii in anoxia. J Biol Chem 2015; 290:8666-76. [PMID: 25691575 DOI: 10.1074/jbc.m114.632588] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Photosynthetic microalgae are exposed to changing environmental conditions. In particular, microbes found in ponds or soils often face hypoxia or even anoxia, and this severely impacts their physiology. Chlamydomonas reinhardtii is one among such photosynthetic microorganisms recognized for its unusual wealth of fermentative pathways and the extensive remodeling of its metabolism upon the switch to anaerobic conditions. As regards the photosynthetic electron transfer, this remodeling encompasses a strong limitation of the electron flow downstream of photosystem I. Here, we further characterize the origin of this limitation. We show that it stems from the strong reducing pressure that builds up upon the onset of anoxia, and this pressure can be relieved either by the light-induced synthesis of ATP, which promotes the consumption of reducing equivalents, or by the progressive activation of the hydrogenase pathway, which provides an electron transfer pathway alternative to the CO2 fixation cycle.
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Affiliation(s)
- Sophie Clowez
- From the Institut de Biologie Physico-Chimique, UMR 7141 CNRS-UPMC, 13 Rue P et M Curie, 75005 Paris, France, and
| | - Damien Godaux
- the Laboratoire de Génétique et Physiologie des Microalgues, Phytosystems, Department of Life Sciences, Institute of Botany, 27 Bld. du Rectorat, University of Liège, B-4000 Liège, Belgium
| | - Pierre Cardol
- the Laboratoire de Génétique et Physiologie des Microalgues, Phytosystems, Department of Life Sciences, Institute of Botany, 27 Bld. du Rectorat, University of Liège, B-4000 Liège, Belgium
| | - Francis-André Wollman
- From the Institut de Biologie Physico-Chimique, UMR 7141 CNRS-UPMC, 13 Rue P et M Curie, 75005 Paris, France, and
| | - Fabrice Rappaport
- From the Institut de Biologie Physico-Chimique, UMR 7141 CNRS-UPMC, 13 Rue P et M Curie, 75005 Paris, France, and
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102
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Siebel JF, Adamska-Venkatesh A, Weber K, Rumpel S, Reijerse E, Lubitz W. Hybrid [FeFe]-hydrogenases with modified active sites show remarkable residual enzymatic activity. Biochemistry 2015; 54:1474-83. [PMID: 25633077 DOI: 10.1021/bi501391d] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
[FeFe]-hydrogenases are to date the only enzymes for which it has been demonstrated that the native inorganic binuclear cofactor of the active site Fe2(adt)(CO)3(CN)2 (adt = azadithiolate = [S-CH2-NH-CH2-S](2-)) can be synthesized on the laboratory bench and subsequently inserted into the unmaturated enzyme to yield fully functional holo-enzyme (Berggren, G. et al. (2013) Nature 499, 66-70; Esselborn, J. et al. (2013) Nat. Chem. Biol. 9, 607-610). In the current study, we exploit this procedure to introduce non-native cofactors into the enzyme. Mimics of the binuclear subcluster with a modified bridging dithiolate ligand (thiodithiolate, N-methylazadithiolate, dimethyl-azadithiolate) and three variants containing only one CN(-) ligand were inserted into the active site of the enzyme. We investigated the activity of these variants for hydrogen oxidation as well as proton reduction and their structural accommodation within the active site was analyzed using Fourier transform infrared spectroscopy. Interestingly, the monocyanide variant with the azadithiolate bridge showed ∼50% of the native enzyme activity. This would suggest that the CN(-) ligands are not essential for catalytic activity, but rather serve to anchor the binuclear subsite inside the protein pocket through hydrogen bonding. The inserted artificial cofactors with a propanedithiolate and an N-methylazadithiolate bridge as well as their monocyanide variants also showed residual activity. However, these activities were less than 1% of the native enzyme. Our findings indicate that even small changes in the dithiolate bridge of the binuclear subsite lead to a rather strong decrease of the catalytic activity. We conclude that both the Brønsted base function and the conformational flexibility of the native azadithiolate amine moiety are essential for the high catalytic activity of the native enzyme.
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Affiliation(s)
- Judith F Siebel
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D-45470 Muelheim an der Ruhr, Germany
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X-ray crystallographic and EPR spectroscopic analysis of HydG, a maturase in [FeFe]-hydrogenase H-cluster assembly. Proc Natl Acad Sci U S A 2015; 112:1362-7. [PMID: 25605932 DOI: 10.1073/pnas.1417252112] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Hydrogenases use complex metal cofactors to catalyze the reversible formation of hydrogen. In [FeFe]-hydrogenases, the H-cluster cofactor includes a diiron subcluster containing azadithiolate, three CO, and two CN(-) ligands. During the assembly of the H cluster, the radical S-adenosyl methionine (SAM) enzyme HydG lyses the substrate tyrosine to yield the diatomic ligands. These diatomic products form an enzyme-bound Fe(CO)x(CN)y synthon that serves as a precursor for eventual H-cluster assembly. To further elucidate the mechanism of this complex reaction, we report the crystal structure and EPR analysis of HydG. At one end of the HydG (βα)8 triosephosphate isomerase (TIM) barrel, a canonical [4Fe-4S] cluster binds SAM in close proximity to the proposed tyrosine binding site. At the opposite end of the active-site cavity, the structure reveals the auxiliary Fe-S cluster in two states: one monomer contains a [4Fe-5S] cluster, and the other monomer contains a [5Fe-5S] cluster consisting of a [4Fe-4S] cubane bridged by a μ2-sulfide ion to a mononuclear Fe(2+) center. This fifth iron is held in place by a single highly conserved protein-derived ligand: histidine 265. EPR analysis confirms the presence of the [5Fe-5S] cluster, which on incubation with cyanide, undergoes loss of the labile iron to yield a [4Fe-4S] cluster. We hypothesize that the labile iron of the [5Fe-5S] cluster is the site of Fe(CO)x(CN)y synthon formation and that the limited bonding between this iron and HydG may facilitate transfer of the intact synthon to its cognate acceptor for subsequent H-cluster assembly.
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104
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Lanz ND, Booker SJ. Auxiliary iron-sulfur cofactors in radical SAM enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1316-34. [PMID: 25597998 DOI: 10.1016/j.bbamcr.2015.01.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/15/2014] [Accepted: 01/06/2015] [Indexed: 11/19/2022]
Abstract
A vast number of enzymes are now known to belong to a superfamily known as radical SAM, which all contain a [4Fe-4S] cluster ligated by three cysteine residues. The remaining, unligated, iron ion of the cluster binds in contact with the α-amino and α-carboxylate groups of S-adenosyl-l-methionine (SAM). This binding mode facilitates inner-sphere electron transfer from the reduced form of the cluster into the sulfur atom of SAM, resulting in a reductive cleavage of SAM to methionine and a 5'-deoxyadenosyl radical. The 5'-deoxyadenosyl radical then abstracts a target substrate hydrogen atom, initiating a wide variety of radical-based transformations. A subset of radical SAM enzymes contains one or more additional iron-sulfur clusters that are required for the reactions they catalyze. However, outside of a subset of sulfur insertion reactions, very little is known about the roles of these additional clusters. This review will highlight the most recent advances in the identification and characterization of radical SAM enzymes that harbor auxiliary iron-sulfur clusters. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
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Affiliation(s)
- Nicholas D Lanz
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States
| | - Squire J Booker
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States; Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, United States.
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105
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Nicolet Y, Pagnier A, Zeppieri L, Martin L, Amara P, Fontecilla-Camps JC. Crystal Structure of HydG fromCarboxydothermus hydrogenoformans: A Trifunctional [FeFe]-Hydrogenase Maturase. Chembiochem 2014; 16:397-402. [DOI: 10.1002/cbic.201402661] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Indexed: 11/10/2022]
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106
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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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107
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Scoma A, Durante L, Bertin L, Fava F. Acclimation to hypoxia in Chlamydomonas reinhardtii: can biophotolysis be the major trigger for long-term H2 production? THE NEW PHYTOLOGIST 2014; 204:890-900. [PMID: 25103459 DOI: 10.1111/nph.12964] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 07/04/2014] [Indexed: 05/10/2023]
Abstract
In anaerobiosis, the microalga Chlamydomonas reinhardtii is able to produce H2 gas. Electrons mainly derive from mobilization of internal reserves or from water through biophotolysis. However, the exact mechanisms triggering this process are still unclear. Our hypothesis was that, once a proper redox state has been achieved, H2 production is eventually observed. To avoid nutrient depletion, which would result in enhanced fermentative pathways, we aimed to induce long-lasting H2 production solely through a photosynthesis : respiration equilibrium. Thus, growing cells were incubated in Tris Acetate Phosphate (TAP) medium under low light and high chlorophyll content. After a 250-h acclimation phase, a 350-h H2 production phase was observed. The light-to-H2 conversion efficiency was comparable to that given in some reports operating under sulphur starvation. Electron sources were found to be water, through biophotolysis, and proteins, particularly through photofermentation. Nonetheless, a substantial contribution from acetate could not be ruled out. In addition, photosystem II (PSII) inhibition by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) showed that it actively contributed to maintaining a redox balance during cell acclimation. In appropriate conditions, PSII may represent the major source of reducing power to feed the H2 evolution process, by inducing and maintaining an ideal excess of reducing power.
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Affiliation(s)
- Alberto Scoma
- Department of Civil, Chemical, Environmental and Materials Engineering (DICAM), School of Engineering and Architecture, Alma Mater Studiorum, University of Bologna, Via U. Terracini 28, I-40131, Bologna, Italy
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108
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Peters JW, Schut GJ, Boyd ES, Mulder DW, Shepard EM, Broderick JB, King PW, Adams MWW. [FeFe]- and [NiFe]-hydrogenase diversity, mechanism, and maturation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1350-69. [PMID: 25461840 DOI: 10.1016/j.bbamcr.2014.11.021] [Citation(s) in RCA: 268] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/10/2014] [Accepted: 11/16/2014] [Indexed: 11/29/2022]
Abstract
The [FeFe]- and [NiFe]-hydrogenases catalyze the formal interconversion between hydrogen and protons and electrons, possess characteristic non-protein ligands at their catalytic sites and thus share common mechanistic features. Despite the similarities between these two types of hydrogenases, they clearly have distinct evolutionary origins and likely emerged from different selective pressures. [FeFe]-hydrogenases are widely distributed in fermentative anaerobic microorganisms and likely evolved under selective pressure to couple hydrogen production to the recycling of electron carriers that accumulate during anaerobic metabolism. In contrast, many [NiFe]-hydrogenases catalyze hydrogen oxidation as part of energy metabolism and were likely key enzymes in early life and arguably represent the predecessors of modern respiratory metabolism. Although the reversible combination of protons and electrons to generate hydrogen gas is the simplest of chemical reactions, the [FeFe]- and [NiFe]-hydrogenases have distinct mechanisms and differ in the fundamental chemistry associated with proton transfer and control of electron flow that also help to define catalytic bias. A unifying feature of these enzymes is that hydrogen activation itself has been restricted to one solution involving diatomic ligands (carbon monoxide and cyanide) bound to an Fe ion. On the other hand, and quite remarkably, the biosynthetic mechanisms to produce these ligands are exclusive to each type of enzyme. Furthermore, these mechanisms represent two independent solutions to the formation of complex bioinorganic active sites for catalyzing the simplest of chemical reactions, reversible hydrogen oxidation. As such, the [FeFe]- and [NiFe]-hydrogenases are arguably the most profound case of convergent evolution. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
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Affiliation(s)
- John W Peters
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA.
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Eric S Boyd
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT 59717, USA
| | - David W Mulder
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Eric M Shepard
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Joan B Broderick
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Paul W King
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
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109
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110
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Chernev P, Lambertz C, Brünje A, Leidel N, Sigfridsson KGV, Kositzki R, Hsieh CH, Yao S, Schiwon R, Driess M, Limberg C, Happe T, Haumann M. Hydride Binding to the Active Site of [FeFe]-Hydrogenase. Inorg Chem 2014; 53:12164-77. [DOI: 10.1021/ic502047q] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Petko Chernev
- Institute for Experimental
Physics, Free University Berlin, 14195 Berlin, Germany
| | - Camilla Lambertz
- Institute for Biochemistry of Plants, Department
of Photobiotechnology, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Annika Brünje
- Institute for Biochemistry of Plants, Department
of Photobiotechnology, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Nils Leidel
- Institute for Experimental
Physics, Free University Berlin, 14195 Berlin, Germany
| | | | - Ramona Kositzki
- Institute for Experimental
Physics, Free University Berlin, 14195 Berlin, Germany
| | - Chung-Hung Hsieh
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Shenglai Yao
- Department of Chemistry, Technical University Berlin, 10623 Berlin, Germany
| | - Rafael Schiwon
- Department of Chemistry, Humboldt University Berlin, 12489 Berlin, Germany
| | - Matthias Driess
- Department of Chemistry, Technical University Berlin, 10623 Berlin, Germany
| | - Christian Limberg
- Department of Chemistry, Humboldt University Berlin, 12489 Berlin, Germany
| | - Thomas Happe
- Institute for Biochemistry of Plants, Department
of Photobiotechnology, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Michael Haumann
- Institute for Experimental
Physics, Free University Berlin, 14195 Berlin, Germany
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111
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Yang W, Catalanotti C, D'Adamo S, Wittkopp TM, Ingram-Smith CJ, Mackinder L, Miller TE, Heuberger AL, Peers G, Smith KS, Jonikas MC, Grossman AR, Posewitz MC. Alternative acetate production pathways in Chlamydomonas reinhardtii during dark anoxia and the dominant role of chloroplasts in fermentative acetate production. THE PLANT CELL 2014; 26:4499-518. [PMID: 25381350 PMCID: PMC4277214 DOI: 10.1105/tpc.114.129965] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 07/15/2014] [Accepted: 10/15/2014] [Indexed: 05/18/2023]
Abstract
Chlamydomonas reinhardtii insertion mutants disrupted for genes encoding acetate kinases (EC 2.7.2.1) (ACK1 and ACK2) and a phosphate acetyltransferase (EC 2.3.1.8) (PAT2, but not PAT1) were isolated to characterize fermentative acetate production. ACK1 and PAT2 were localized to chloroplasts, while ACK2 and PAT1 were shown to be in mitochondria. Characterization of the mutants showed that PAT2 and ACK1 activity in chloroplasts plays a dominant role (relative to ACK2 and PAT1 in mitochondria) in producing acetate under dark, anoxic conditions and, surprisingly, also suggested that Chlamydomonas has other pathways that generate acetate in the absence of ACK activity. We identified a number of proteins associated with alternative pathways for acetate production that are encoded on the Chlamydomonas genome. Furthermore, we observed that only modest alterations in the accumulation of fermentative products occurred in the ack1, ack2, and ack1 ack2 mutants, which contrasts with the substantial metabolite alterations described in strains devoid of other key fermentation enzymes.
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Affiliation(s)
- Wenqiang Yang
- Carnegie Institution for Science, Department of Plant Biology, Stanford, California 94305
| | - Claudia Catalanotti
- Carnegie Institution for Science, Department of Plant Biology, Stanford, California 94305
| | - Sarah D'Adamo
- Colorado School of Mines, Department of Chemistry and Geochemistry, Golden, Colorado 80401
| | - Tyler M Wittkopp
- Carnegie Institution for Science, Department of Plant Biology, Stanford, California 94305 Stanford University, Department of Biology, Stanford, California 94305
| | - Cheryl J Ingram-Smith
- Clemson University, Department of Genetics and Biochemistry, Clemson, South Carolina 29634
| | - Luke Mackinder
- Carnegie Institution for Science, Department of Plant Biology, Stanford, California 94305
| | - Tarryn E Miller
- Colorado School of Mines, Department of Chemistry and Geochemistry, Golden, Colorado 80401
| | - Adam L Heuberger
- Colorado State University, Proteomics and Metabolomics Facility, Fort Collins, Colorado 80523
| | - Graham Peers
- Colorado State University, Department of Biology, Fort Collins, Colorado 80523
| | - Kerry S Smith
- Clemson University, Department of Genetics and Biochemistry, Clemson, South Carolina 29634
| | - Martin C Jonikas
- Carnegie Institution for Science, Department of Plant Biology, Stanford, California 94305
| | - Arthur R Grossman
- Carnegie Institution for Science, Department of Plant Biology, Stanford, California 94305
| | - Matthew C Posewitz
- Colorado School of Mines, Department of Chemistry and Geochemistry, Golden, Colorado 80401
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112
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Duffus BR, Ghose S, Peters JW, Broderick JB. Reversible H atom abstraction catalyzed by the radical S-adenosylmethionine enzyme HydG. J Am Chem Soc 2014; 136:13086-9. [PMID: 25099480 PMCID: PMC4183638 DOI: 10.1021/ja504618y] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The organometallic H-cluster at the active site of [FeFe]-hydrogenases is synthesized by three accessory proteins, two of which are radical S-adenosylmethionine enzymes (HydE, HydG) and one of which is a GTPase (HydF). In this work we probed the specific role of H atom abstraction in HydG-catalyzed carbon monoxide and cyanide production from tyrosine. The isotope distributions of 5'-deoxyadenosine and p-cresol were evaluated using deuterium-labeled tyrosine substrates in H2O and D2O. The observation of multiply deuterated 5'-deoxyadenosine and deuterated S-adenosylmethionine when the reaction is carried out in D2O provides evidence for a 5'-deoxyadenosyl radical-mediated abstraction of a hydrogen atom from a solvent-exchangeable position as a reversible event.
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Affiliation(s)
- Benjamin R Duffus
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
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113
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Akhtar MK, Jones PR. Cofactor engineering for enhancing the flux of metabolic pathways. Front Bioeng Biotechnol 2014; 2:30. [PMID: 25221776 PMCID: PMC4147997 DOI: 10.3389/fbioe.2014.00030] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/12/2014] [Indexed: 11/24/2022] Open
Abstract
The manufacture of a diverse array of chemicals is now possible with biologically engineered strains, an approach that is greatly facilitated by the emergence of synthetic biology. This is principally achieved through pathway engineering in which enzyme activities are coordinated within a genetically amenable host to generate the product of interest. A great deal of attention is typically given to the quantitative levels of the enzymes with little regard to their overall qualitative states. This highly constrained approach fails to consider other factors that may be necessary for enzyme functionality. In particular, enzymes with physically bound cofactors, otherwise known as holoenzymes, require careful evaluation. Herein, we discuss the importance of cofactors for biocatalytic processes and show with empirical examples why the synthesis and integration of cofactors for the formation of holoenzymes warrant a great deal of attention within the context of pathway engineering.
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Affiliation(s)
- M Kalim Akhtar
- Department of Biochemical Engineering, University College London , London , UK
| | - Patrik R Jones
- Department of Life Sciences, Imperial College London , London , UK
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114
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Cammack R, Balk J. Iron-sulfur Clusters. BINDING, TRANSPORT AND STORAGE OF METAL IONS IN BIOLOGICAL CELLS 2014. [DOI: 10.1039/9781849739979-00333] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Iron-sulfur clusters are universally distributed groups occurring in iron-sulfur proteins. They have a wide range of cellular functions which reflect the chemistry of the clusters. Some clusters are involved in electron transport and energy transduction in photosynthesis and respiration. Others can bind substrates and participate in enzyme catalysis. Regulatory functions have also been documented for clusters that respond to oxygen partial pressure and iron availability. Finally, there are some for which no function has been defined; they may act as stabilizing structures, for example, in enzymes involved in nucleic acid metabolism. The clusters are constructed intracellularly and inserted into proteins, which can then be transported to intracellular targets, in some cases, across membranes. Three different types of iron-sulfur cluster assembly machinery have evolved in prokaryotes: NIF, ISC and SUF. Each system involves a scaffold protein on which the cluster is constructed (encoded by genes nifU, iscU, sufU or sufB) and a cysteine desulfurase (encoded by nifS, iscS or sufS) which provides the sulfide sulfur. In eukaryotic cells, clusters are formed in the mitochondria for the many iron-sulfur proteins in this organelle. The mitochondrial biosynthesis pathway is linked to the cytoplasmic iron-sulfur assembly system (CIA) for the maturation of cytoplasmic and nuclear iron-sulfur proteins. In plant cells, a SUF-type system is used for cluster assembly in the plastids. Many accessory proteins are involved in cluster transfer before insertion into the appropriate sites in Fe-S proteins.
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Affiliation(s)
- Richard Cammack
- King's College London, Department of Biochemistry, 150 Stamford Street London SE1 9NH UK
| | - Janneke Balk
- John Innes Centre and University of East Anglia Norwich Research Park, Colney Lane Norwich NR4 7UH UK
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115
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Broderick JB, Byer AS, Duschene KS, Duffus BR, Betz JN, Shepard EM, Peters JW. H-cluster assembly during maturation of the [FeFe]-hydrogenase. J Biol Inorg Chem 2014; 19:747-57. [PMID: 24972661 DOI: 10.1007/s00775-014-1168-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 06/03/2014] [Indexed: 11/28/2022]
Abstract
The organometallic H-cluster at the active site of the [FeFe]-hydrogenase serves as the site of reversible binding and reduction of protons to produce H2. The H-cluster is unique in biology, and consists of a 2Fe subcluster tethered to a typical [4Fe-4S] cluster by a single cysteine ligand. The remaining ligands to the 2Fe subcluster include three carbon monoxides, two cyanides, and a dithiomethylamine. This mini-review will focus on the significant advances in recent years in understanding the pathway for H-cluster biosynthesis, as well as the structures, roles, and mechanisms of the three enzymes directly involved.
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Affiliation(s)
- Joan B Broderick
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT, 59717, USA,
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116
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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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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: 576] [Impact Index Per Article: 57.6] [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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118
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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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119
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Wecker MSA, Ghirardi ML. High-throughput biosensor discriminates between different algal H2 -photoproducing strains. Biotechnol Bioeng 2014; 111:1332-40. [PMID: 24578287 DOI: 10.1002/bit.25206] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/15/2014] [Accepted: 01/28/2014] [Indexed: 12/24/2022]
Abstract
A number of species of microalgae and cyanobacteria photosynthetically produce H2 gas by coupling water oxidation with the reduction of protons to molecular hydrogen, generating renewable energy from sunlight and water. Photosynthetic H2 production, however, is transitory, and there is considerable interest in increasing and extending it for commercial applications. Here we report a Petri-plate version of our previous, microplate-based assay that detects photosynthetic H2 production by algae. The assay consists of an agar overlay of H2 -sensing Rhodobacter capsulatus bacteria carrying a green fluorescent protein that responds to H2 produced by single algal colonies in the bottom agar layer. The assay distinguishes between algal strains that photoproduce H2 at different levels under high light intensities, and it does so in a simple, inexpensive, and high-throughput manner. The assay will be useful for screening both natural populations and mutant libraries for strains having increased H2 production, and useful for identifying various genetic factors that physiologically or genetically alter algal hydrogen production.
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120
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D'Adamo S, Jinkerson RE, Boyd ES, Brown SL, Baxter BK, Peters JW, Posewitz MC. Evolutionary and biotechnological implications of robust hydrogenase activity in halophilic strains of Tetraselmis. PLoS One 2014; 9:e85812. [PMID: 24465722 PMCID: PMC3897525 DOI: 10.1371/journal.pone.0085812] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 12/02/2013] [Indexed: 11/19/2022] Open
Abstract
Although significant advances in H2 photoproduction have recently been realized in fresh water algae (e.g. Chlamydomonas reinhardtii), relatively few studies have focused on H2 production and hydrogenase adaptations in marine or halophilic algae. Salt water organisms likely offer several advantages for biotechnological H2 production due to the global abundance of salt water, decreased H2 and O2 solubility in saline and hypersaline systems, and the ability of extracellular NaCl levels to influence metabolism. We screened unialgal isolates obtained from hypersaline ecosystems in the southwest United States and identified two distinct halophilic strains of the genus Tetraselmis (GSL1 and QNM1) that exhibit both robust fermentative and photo H2-production activities. The influence of salinity (3.5%, 5.5% and 7.0% w/v NaCl) on H2 production was examined during anoxic acclimation, with the greatest in vivo H2-production rates observed at 7.0% NaCl. These Tetraselmis strains maintain robust hydrogenase activity even after 24 h of anoxic acclimation and show increased hydrogenase activity relative to C. reinhardtii after extended anoxia. Transcriptional analysis of Tetraselmis GSL1 enabled sequencing of the cDNA encoding the FeFe-hydrogenase structural enzyme (HYDA) and its maturation proteins (HYDE, HYDEF and HYDG). In contrast to freshwater Chlorophyceae, the halophilic Tetraselmis GSL1 strain likely encodes a single HYDA and two copies of HYDE, one of which is fused to HYDF. Phylogenetic analyses of HYDA and concatenated HYDA, HYDE, HYDF and HYDG in Tetraselmis GSL1 fill existing knowledge gaps in the evolution of algal hydrogenases and indicate that the algal hydrogenases sequenced to date are derived from a common ancestor. This is consistent with recent hypotheses that suggest fermentative metabolism in the majority of eukaryotes is derived from a common base set of enzymes that emerged early in eukaryotic evolution with subsequent losses in some organisms.
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Affiliation(s)
- Sarah D'Adamo
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, Colorado, United States of America
| | - Robert E. Jinkerson
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, Colorado, United States of America
| | - Eric S. Boyd
- Department of Microbiology and the Thermal Biology Institute, Montana State University, Bozeman, Montana, United States of America
| | - Susan L. Brown
- Center for Marine Microbial Ecology and Diversity, University of Hawaii, Honolulu, Hawaii, United States of America
| | - Bonnie K. Baxter
- Department of Biology and the Great Salt Lake Institute, Westminster College, Salt Lake City, Utah, United States of America
| | - John W. Peters
- Department of Microbiology and the Thermal Biology Institute, Montana State University, Bozeman, Montana, United States of America
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, United States of America
| | - Matthew C. Posewitz
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, Colorado, United States of America
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Kuchenreuther JM, Shiigi SA, Swartz JR. Cell-free synthesis of the H-cluster: a model for the in vitro assembly of metalloprotein metal centers. Methods Mol Biol 2014; 1122:49-72. [PMID: 24639253 DOI: 10.1007/978-1-62703-794-5_5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many organometallic cofactors are highly complex and require multiple accessory proteins for both their assembly and transfer to a target protein. A cell-free system in which the biosynthetic pathway for a prosthetic group has been fully or even partially reconstructed enables investigations of the reaction sequence as well as the cofactor itself. As a model for the in vitro assembly of protein-bound metal centers, we describe a procedure for the cell-free synthesis of the H-cluster in the context of producing purified and active [FeFe] hydrogenase samples for spectroscopic studies. In general terms, this in vitro system is a combination of non-purified accessory proteins, exogenous substrates, and purified hydrogenase apoprotein. We also describe methods for making the required components used in the cell-free system. Specifically, these procedures include anaerobic expression of heterologous metalloproteins in Escherichia coli, anaerobic cell lysate production, and anaerobic metalloprotein purification using Strep-Tactin(®) chromatography.
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Affiliation(s)
- Jon M Kuchenreuther
- Department of Chemical Engineering, Stanford University, 381 North South Mall, Stanford, CA, 94305-5025, USA,
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122
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Zimorski V, Martin WF. Subcellular targeting of proteins and pathways during evolution. THE NEW PHYTOLOGIST 2014; 201:1-2. [PMID: 24274788 DOI: 10.1111/nph.12566] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- Verena Zimorski
- Institute of Molecular Evolution, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - William F Martin
- Institute of Molecular Evolution, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
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123
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Sun X, Perera S, Haas N, Lefebvre PA, Silflow CD. Using an RSP3 reporter gene system to investigate molecular regulation of hydrogenase expression in Chlamydomonas reinhardtii. ALGAL RES 2013. [DOI: 10.1016/j.algal.2013.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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124
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Leger MM, Gawryluk RMR, Gray MW, Roger AJ. Evidence for a hydrogenosomal-type anaerobic ATP generation pathway in Acanthamoeba castellanii. PLoS One 2013; 8:e69532. [PMID: 24086244 PMCID: PMC3785491 DOI: 10.1371/journal.pone.0069532] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 06/13/2013] [Indexed: 11/18/2022] Open
Abstract
Diverse, distantly-related eukaryotic lineages have adapted to low-oxygen environments, and possess mitochondrion-related organelles that have lost the capacity to generate adenosine triphosphate (ATP) through oxidative phosphorylation. A subset of these organelles, hydrogenosomes, has acquired a set of characteristic ATP generation enzymes commonly found in anaerobic bacteria. The recipient of these enzymes could not have survived prior to their acquisition had it not still possessed the electron transport chain present in the ancestral mitochondrion. In the divergence of modern hydrogenosomes from mitochondria, a transitional organelle must therefore have existed that possessed both an electron transport chain and an anaerobic ATP generation pathway. Here, we report a modern analog of this organelle in the habitually aerobic opportunistic pathogen, Acanthamoeba castellanii. This organism possesses a complete set of enzymes comprising a hydrogenosome-like ATP generation pathway, each of which is predicted to be targeted to mitochondria. We have experimentally confirmed the mitochondrial localizations of key components of this pathway using tandem mass spectrometry. This evidence is the first supported by localization and proteome data of a mitochondrion possessing both an electron transport chain and hydrogenosome-like energy metabolism enzymes. Our work provides insight into the first steps that might have occurred in the course of the emergence of modern hydrogenosomes.
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Affiliation(s)
- Michelle M. Leger
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Ryan M. R. Gawryluk
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Michael W. Gray
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Andrew J. Roger
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
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Hemschemeier A, Casero D, Liu B, Benning C, Pellegrini M, Happe T, Merchant SS. Copper response regulator1-dependent and -independent responses of the Chlamydomonas reinhardtii transcriptome to dark anoxia. THE PLANT CELL 2013; 25:3186-211. [PMID: 24014546 PMCID: PMC3809527 DOI: 10.1105/tpc.113.115741] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Anaerobiosis is a stress condition for aerobic organisms and requires extensive acclimation responses. We used RNA-Seq for a whole-genome view of the acclimation of Chlamydomonas reinhardtii to anoxic conditions imposed simultaneously with transfer to the dark. Nearly 1.4 × 10(3) genes were affected by hypoxia. Comparing transcript profiles from early (hypoxic) with those from late (anoxic) time points indicated that cells activate oxidative energy generation pathways before employing fermentation. Probable substrates include amino acids and fatty acids (FAs). Lipid profiling of the C. reinhardtii cells revealed that they degraded FAs but also accumulated triacylglycerols (TAGs). In contrast with N-deprived cells, the TAGs in hypoxic cells were enriched in desaturated FAs, suggesting a distinct pathway for TAG accumulation. To distinguish transcriptional responses dependent on copper response regulator1 (CRR1), which is also involved in hypoxic gene regulation, we compared the transcriptomes of crr1 mutants and complemented strains. In crr1 mutants, ~40 genes were aberrantly regulated, reaffirming the importance of CRR1 for the hypoxic response, but indicating also the contribution of additional signaling strategies to account for the remaining differentially regulated transcripts. Based on transcript patterns and previous results, we conclude that nitric oxide-dependent signaling cascades operate in anoxic C. reinhardtii cells.
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Affiliation(s)
- Anja Hemschemeier
- Ruhr Universität Bochum, Fakultät für Biologie und Biotechnologie, Arbeitsgruppe Photobiotechnologie, 44801 Bochum, Germany
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Lin HD, Liu BH, Kuo TT, Tsai HC, Feng TY, Huang CC, Chien LF. Knockdown of PsbO leads to induction of HydA and production of photobiological H2 in the green alga Chlorella sp. DT. BIORESOURCE TECHNOLOGY 2013; 143:154-62. [PMID: 23792754 DOI: 10.1016/j.biortech.2013.05.101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 05/26/2013] [Accepted: 05/27/2013] [Indexed: 05/09/2023]
Abstract
Green algae are able to convert solar energy to H2 via the photosynthetic electron transport pathway under certain conditions. Algal hydrogenase (HydA, encoded by HYDA) is in charge of catalyzing the reaction: 2H(+)+2e(-)↔H2 but usually inhibited by O2, a byproduct of photosynthesis. The aim of this study was to knockdown PsbO (encoded by psbO), a subunit concerned with O2 evolution, so that it would lead to HydA induction. The alga, Chlorella sp. DT, was then transformed with short interference RNA antisense-psbO (siRNA-psbO) fragments. The algal mutants were selected by checking for the existence of siRNA-psbO fragments in their genomes and the low amount of PsbO proteins. The HYDA transcription and the HydA expression were observed in the PsbO-knockdown mutants. Under semi-aerobic condition, PsbO-knockdown mutants could photobiologically produce H2 which increased by as much as 10-fold in comparison to the wild type.
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Affiliation(s)
- Hsin-Di Lin
- Department of Life Sciences, National Chung Hsing University, Taichung 402, Taiwan
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128
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Esselborn J, Lambertz C, Adamska-Venkates A, Simmons T, Berggren G, Noth J, Siebel J, Hemschemeier A, Artero V, Reijerse E, Fontecave M, Lubitz W, Happe T. Spontaneous activation of [FeFe]-hydrogenases by an inorganic [2Fe] active site mimic. Nat Chem Biol 2013; 9:607-609. [PMID: 23934246 DOI: 10.1038/nchembio.1311] [Citation(s) in RCA: 262] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 07/01/2013] [Indexed: 01/01/2023]
Abstract
Hydrogenases catalyze the formation of hydrogen. The cofactor ('H-cluster') of [FeFe]-hydrogenases consists of a [4Fe-4S] cluster bridged to a unique [2Fe] subcluster whose biosynthesis in vivo requires hydrogenase-specific maturases. Here we show that a chemical mimic of the [2Fe] subcluster can reconstitute apo-hydrogenase to full activity, independent of helper proteins. The assembled H-cluster is virtually indistinguishable from the native cofactor. This procedure will be a powerful tool for developing new artificial H₂-producing catalysts.
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Affiliation(s)
- Julian Esselborn
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44801 Bochum, Germany
| | - Camilla Lambertz
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44801 Bochum, Germany
| | - Agnieszka Adamska-Venkates
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Trevor Simmons
- Laboratoire de Chimie et Biologie des Métaux (CEA / Université Grenoble 1 / CNRS), 17 rue des Martyrs, F-38054 Grenoble cedex 9, France
| | - Gustav Berggren
- Laboratoire de Chimie et Biologie des Métaux (CEA / Université Grenoble 1 / CNRS), 17 rue des Martyrs, F-38054 Grenoble cedex 9, France
| | - Jens Noth
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44801 Bochum, Germany
| | - Judith Siebel
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Anja Hemschemeier
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44801 Bochum, Germany
| | - Vincent Artero
- Laboratoire de Chimie et Biologie des Métaux (CEA / Université Grenoble 1 / CNRS), 17 rue des Martyrs, F-38054 Grenoble cedex 9, France
| | - Edward Reijerse
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Marc Fontecave
- Laboratoire de Chimie et Biologie des Métaux (CEA / Université Grenoble 1 / CNRS), 17 rue des Martyrs, F-38054 Grenoble cedex 9, France.,Collège de France, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Wolfgang Lubitz
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Thomas Happe
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44801 Bochum, Germany
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Ghysels B, Godaux D, Matagne RF, Cardol P, Franck F. Function of the chloroplast hydrogenase in the microalga Chlamydomonas: the role of hydrogenase and state transitions during photosynthetic activation in anaerobiosis. PLoS One 2013; 8:e64161. [PMID: 23717558 PMCID: PMC3662714 DOI: 10.1371/journal.pone.0064161] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 04/10/2013] [Indexed: 01/12/2023] Open
Abstract
Like a majority of photosynthetic microorganisms, the green unicellular alga Chlamydomonas reinhardtii may encounter O2 deprived conditions on a regular basis. In response to anaerobiosis or in a respiration defective context, the photosynthetic electron transport chain of Chlamydomonas is remodeled by a state transition process to a conformation that favours the photoproduction of ATP at the expense of reductant synthesis. In some unicellular green algae including Chlamydomonas, anoxia also triggers the induction of a chloroplast-located, oxygen sensitive hydrogenase, which accepts electrons from reduced ferredoxin to convert protons into molecular hydrogen. Although microalgal hydrogen evolution has received much interest for its biotechnological potential, its physiological role remains unclear. By using specific Chlamydomonas mutants, we demonstrate that the state transition ability and the hydrogenase function are both critical for induction of photosynthesis in anoxia. These two processes are thus important for survival of the cells when they are transiently placed in an anaerobic environment.
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Affiliation(s)
- Bart Ghysels
- Laboratory of Bioenergetics, Institute of Plant Biology B22, University of Liège, Liège, Belgium
| | - Damien Godaux
- Laboratory of Genetics of Microorganisms, Institute of Plant Biology B22, University of Liège, Liège, Belgium
| | - René F. Matagne
- Laboratory of Genetics of Microorganisms, Institute of Plant Biology B22, University of Liège, Liège, Belgium
| | - Pierre Cardol
- Laboratory of Genetics of Microorganisms, Institute of Plant Biology B22, University of Liège, Liège, Belgium
| | - Fabrice Franck
- Laboratory of Bioenergetics, Institute of Plant Biology B22, University of Liège, Liège, Belgium
- * E-mail:
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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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Zubáčová Z, Novák L, Bublíková J, Vacek V, Fousek J, Rídl J, Tachezy J, Doležal P, Vlček Č, Hampl V. The mitochondrion-like organelle of Trimastix pyriformis contains the complete glycine cleavage system. PLoS One 2013; 8:e55417. [PMID: 23516392 PMCID: PMC3596361 DOI: 10.1371/journal.pone.0055417] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 12/22/2012] [Indexed: 11/19/2022] Open
Abstract
All eukaryotic organisms contain mitochondria or organelles that evolved from the same endosymbiotic event like classical mitochondria. Organisms inhabiting low oxygen environments often contain mitochondrial derivates known as hydrogenosomes, mitosomes or neutrally as mitochondrion-like organelles. The detailed investigation has shown unexpected evolutionary plasticity in the biochemistry and protein composition of these organelles in various protists. We investigated the mitochondrion-like organelle in Trimastix pyriformis, a free-living member of one of the three lineages of anaerobic group Metamonada. Using 454 sequencing we have obtained 7 037 contigs from its transcriptome and on the basis of sequence homology and presence of N-terminal extensions we have selected contigs coding for proteins that putatively function in the organelle. Together with the results of a previous transcriptome survey, the list now consists of 23 proteins - mostly enzymes involved in amino acid metabolism, transporters and maturases of proteins and transporters of metabolites. We have no evidence of the production of ATP in the mitochondrion-like organelle of Trimastix but we have obtained experimental evidence for the presence of enzymes of the glycine cleavage system (GCS), which is part of amino acid metabolism. Using homologous antibody we have shown that H-protein of GCS localizes into vesicles in the cell of Trimastix. When overexpressed in yeast, H- and P-protein of GCS and cpn60 were transported into mitochondrion. In case of H-protein we have demonstrated that the first 16 amino acids are necessary for this transport. Glycine cleavage system is at the moment the only experimentally localized pathway in the mitochondrial derivate of Trimastix pyriformis.
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Affiliation(s)
- Zuzana Zubáčová
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Lukáš Novák
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Jitka Bublíková
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Vojtěch Vacek
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Jan Fousek
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jakub Rídl
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jan Tachezy
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Pavel Doležal
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
| | - Čestmír Vlček
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Vladimír Hampl
- Charles University in Prague, Faculty of Science, Department of Parasitology, Prague, Czech Republic
- * E-mail:
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Banti V, Giuntoli B, Gonzali S, Loreti E, Magneschi L, Novi G, Paparelli E, Parlanti S, Pucciariello C, Santaniello A, Perata P. Low oxygen response mechanisms in green organisms. Int J Mol Sci 2013; 14:4734-61. [PMID: 23446868 PMCID: PMC3634410 DOI: 10.3390/ijms14034734] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 02/20/2013] [Accepted: 02/21/2013] [Indexed: 01/04/2023] Open
Abstract
Low oxygen stress often occurs during the life of green organisms, mostly due to the environmental conditions affecting oxygen availability. Both plants and algae respond to low oxygen by resetting their metabolism. The shift from mitochondrial respiration to fermentation is the hallmark of anaerobic metabolism in most organisms. This involves a modified carbohydrate metabolism coupled with glycolysis and fermentation. For a coordinated response to low oxygen, plants exploit various molecular mechanisms to sense when oxygen is either absent or in limited amounts. In Arabidopsis thaliana, a direct oxygen sensing system has recently been discovered, where a conserved N-terminal motif on some ethylene responsive factors (ERFs), targets the fate of the protein under normoxia/hypoxia. In Oryza sativa, this same group of ERFs drives physiological and anatomical modifications that vary in relation to the genotype studied. The microalga Chlamydomonas reinhardtii responses to low oxygen seem to have evolved independently of higher plants, posing questions on how the fermentative metabolism is modulated. In this review, we summarize the most recent findings related to these topics, highlighting promising developments for the future.
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Affiliation(s)
- Valeria Banti
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Beatrice Giuntoli
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Silvia Gonzali
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Elena Loreti
- Institute of Agricultural Biology and Biotechnology, National Research Council, Via Moruzzi 1, Pisa 56100, Italy; E-Mail:
| | - Leonardo Magneschi
- Institute of Plant Biochemistry and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany; E-Mail:
| | - Giacomo Novi
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Eleonora Paparelli
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Sandro Parlanti
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Chiara Pucciariello
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Antonietta Santaniello
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
| | - Pierdomenico Perata
- PlantLab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Via Mariscoglio 34, Pisa 56124, Italy; E-Mails: (V.B.); (B.G.); (S.G.); (G.N.); (E.P.); (S.P.); (C.P.); (A.S.)
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134
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Gao W, Francis AJ. Fermentation and hydrogen metabolism affect uranium reduction by clostridia. ISRN BIOTECHNOLOGY 2013; 2013:657160. [PMID: 25937978 PMCID: PMC4393052 DOI: 10.5402/2013/657160] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 01/19/2013] [Indexed: 11/23/2022]
Abstract
Previously, it has been shown that not only is uranium reduction under fermentation condition common among clostridia species, but also the strains differed in the extent of their capability and the pH of the culture significantly affected uranium(VI) reduction. In this study, using HPLC and GC techniques, metabolic properties of those clostridial strains active in uranium reduction under fermentation conditions have been characterized and their effects on capability variance of uranium reduction discussed. Then, the relationship between hydrogen metabolism and uranium reduction has been further explored and the important role played by hydrogenase in uranium(VI) and iron(III) reduction by clostridia demonstrated. When hydrogen was provided as the headspace gas, uranium(VI) reduction occurred in the presence of whole cells of clostridia. This is in contrast to that of nitrogen as the headspace gas. Without clostridia cells, hydrogen alone could not result in uranium(VI) reduction. In alignment with this observation, it was also found that either copper(II) addition or iron depletion in the medium could compromise uranium reduction by clostridia. In the end, a comprehensive model was proposed to explain uranium reduction by clostridia and its relationship to the overall metabolism especially hydrogen (H2) production.
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Affiliation(s)
- Weimin Gao
- Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Arokiasamy J. Francis
- Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
- Environmental Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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135
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Kim JYH, Cha HJ. Recent progress in hydrogenase and its biotechnological application for viable hydrogen technology. KOREAN J CHEM ENG 2013. [DOI: 10.1007/s11814-012-0208-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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136
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Kuchenreuther JM, Guo Y, Wang H, Myers WK, George SJ, Boyke CA, Yoda Y, Alp EE, Zhao J, Britt RD, Swartz JR, Cramer SP. Nuclear resonance vibrational spectroscopy and electron paramagnetic resonance spectroscopy of 57Fe-enriched [FeFe] hydrogenase indicate stepwise assembly of the H-cluster. Biochemistry 2013; 52:818-26. [PMID: 23249091 DOI: 10.1021/bi301336r] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The [FeFe] hydrogenase from Clostridium pasteurianum (CpI) harbors four Fe-S clusters that facilitate the transfer of an electron to the H-cluster, a ligand-coordinated six-iron prosthetic group that catalyzes the redox interconversion of protons and H(2). Here, we have used (57)Fe nuclear resonance vibrational spectroscopy (NRVS) to study the iron centers in CpI, and we compare our data to that for a [4Fe-4S] ferredoxin as well as a model complex resembling the [2Fe](H) catalytic domain of the H-cluster. To enrich the hydrogenase with (57)Fe nuclei, we used cell-free methods to post-translationally mature the enzyme. Specifically, inactive CpI apoprotein with (56)Fe-labeled Fe-S clusters was activated in vitro using (57)Fe-enriched maturation proteins. This approach enabled us to selectively label the [2Fe](H) subcluster with (57)Fe, which NRVS confirms by detecting (57)Fe-CO and (57)Fe-CN normal modes from the H-cluster nonprotein ligands. The NRVS and iron quantification results also suggest that the hydrogenase contains a second (57)Fe-S cluster. Electron paramagnetic resonance (EPR) spectroscopy indicates that this (57)Fe-enriched metal center is not the [4Fe-4S](H) subcluster of the H-cluster. This finding demonstrates that the CpI hydrogenase retained an (56)Fe-enriched [4Fe-4S](H) cluster during in vitro maturation, providing unambiguous evidence of stepwise assembly of the H-cluster. In addition, this work represents the first NRVS characterization of [FeFe] hydrogenases.
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Affiliation(s)
- Jon M Kuchenreuther
- Department of Chemistry, University of California-Davis, CA 95616, United States
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137
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Levin DB, Hye Jo J, Maness PC. Biohydrogen Production from Cellulosic Biomass. INTEGRATED FOREST BIOREFINERIES 2012. [DOI: 10.1039/9781849735063-00256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Hydrogen can be produced by thermochemical, physicochemical, and biological processes. In contrast to thermo- and physicochemical processes, biological processes offer great potential for sustainable, renewable hydrogen production. Lignocellulosic biomass is renewable, inexpensive, constitutes a large fraction of waste biomass from municipal, agricultural, and forestry sectors, and thus offers excellent potential as a feedstock for renewable biofuels. Cellulose is, however, difficult to hydrolyze due to its crystalline structure. Biological hydrogen can be produced from cellulosic substrates by either hydrolyzing cellulose to sugars, followed by fermentation or by direct use of cellulose as the sole carbon source during fermentation. This chapter outlines the microbial basis of biological hydrogen production by cellulolytic bacteria, discusses the factors that influence hydrogen yields, and describes both single-phase and two-phase hydrogen production systems.
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Affiliation(s)
- David B Levin
- Department of Biosystems Engineering University of Manitoba Winnipeg, Manitoba, R3T 5V6 Canada
| | - Ji Hye Jo
- National Renewable Energy Laboratory 1617 Cole Blvd., Golden, Colorado, 80401 USA
| | - Pin-Ching Maness
- National Renewable Energy Laboratory 1617 Cole Blvd., Golden, Colorado, 80401 USA
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138
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Joshi N, Shepard EM, Byer AS, Swanson KD, Broderick JB, Peters JW. Iron-sulfur cluster coordination in the [FeFe]-hydrogenase H cluster biosynthetic factor HydF. FEBS Lett 2012; 586:3939-43. [PMID: 23041346 DOI: 10.1016/j.febslet.2012.09.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Revised: 09/13/2012] [Accepted: 09/19/2012] [Indexed: 02/02/2023]
Abstract
Iron-sulfur cluster coordination was probed in the [FeFe]-hydrogenase H cluster maturation scaffold HydF. Putative Cys thiol and His imidazole ligation identified through multiple sequence alignments and structural studies were subjected to amino acid substitution and the variants were biochemically characterized. The results implicate a role for C304, C353, C356, and H306 of Clostridium acetobutylicum HydF in FeS cluster binding. Individual ligand substitutions affect both [4Fe-4S] and [2Fe-2S] cluster coordination suggesting shared coordination or cluster interconversion. Substitutions at C353 and H306 appear to preferentially impact the presence of the [2Fe-2S] cluster complement of the resulting variants of HydF. The results implicate a potential role for these residues in biosynthesis specifically and potential in bridging the [4Fe-4S] cluster to 2Fe subcluster biosynthetic intermediates.
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Affiliation(s)
- Neelambari Joshi
- Department of Chemistry and Biochemistry, The Astrobiology Biogeocatalysis Research Center, Montana State University, Bozeman, MT 59717, United States
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139
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Dowling DP, Vey JL, Croft AK, Drennan CL. Structural diversity in the AdoMet radical enzyme superfamily. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1824:1178-95. [PMID: 22579873 PMCID: PMC3523193 DOI: 10.1016/j.bbapap.2012.04.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 04/04/2012] [Accepted: 04/19/2012] [Indexed: 11/18/2022]
Abstract
AdoMet radical enzymes are involved in processes such as cofactor biosynthesis, anaerobic metabolism, and natural product biosynthesis. These enzymes utilize the reductive cleavage of S-adenosylmethionine (AdoMet) to afford l-methionine and a transient 5'-deoxyadenosyl radical, which subsequently generates a substrate radical species. By harnessing radical reactivity, the AdoMet radical enzyme superfamily is responsible for an incredible diversity of chemical transformations. Structural analysis reveals that family members adopt a full or partial Triose-phosphate Isomerase Mutase (TIM) barrel protein fold, containing core motifs responsible for binding a catalytic [4Fe-4S] cluster and AdoMet. Here we evaluate over twenty structures of AdoMet radical enzymes and classify them into two categories: 'traditional' and 'ThiC-like' (named for the structure of 4-amino-5-hydroxymethyl-2-methylpyrimidine phosphate synthase (ThiC)). In light of new structural data, we reexamine the 'traditional' structural motifs responsible for binding the [4Fe-4S] cluster and AdoMet, and compare and contrast these motifs with the ThiC case. We also review how structural data combine with biochemical, spectroscopic, and computational data to help us understand key features of this enzyme superfamily, such as the energetics, the triggering, and the molecular mechanisms of AdoMet reductive cleavage. This article is part of a Special Issue entitled: Radical SAM Enzymes and Radical Enzymology.
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Affiliation(s)
- Daniel P. Dowling
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Jessica L. Vey
- Department of Chemistry and Biochemistry, California State University Northridge, Northridge, CA 91330-8262
| | - Anna K. Croft
- School of Chemistry, University of Wales Bangor, Bangor, Gwynedd LL57 2UW, UK
| | - Catherine L. Drennan
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
- Departments of Chemistry and Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
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140
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Kuchenreuther JM, Britt RD, Swartz JR. New insights into [FeFe] hydrogenase activation and maturase function. PLoS One 2012; 7:e45850. [PMID: 23049878 PMCID: PMC3457958 DOI: 10.1371/journal.pone.0045850] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/23/2012] [Indexed: 11/18/2022] Open
Abstract
[FeFe] hydrogenases catalyze H(2) production using the H-cluster, an iron-sulfur cofactor that contains carbon monoxide (CO), cyanide (CN(-)), and a dithiolate bridging ligand. The HydE, HydF, and HydG maturases assist in assembling the H-cluster and maturing hydrogenases into their catalytically active form. Characterization of these maturases and in vitro hydrogenase activation methods have helped elucidate steps in the H-cluster biosynthetic pathway such as the HydG-catalyzed generation of the CO and CN(-) ligands from free tyrosine. We have refined our cell-free approach for H-cluster synthesis and hydrogenase maturation by using separately expressed and purified HydE, HydF, and HydG. In this report, we illustrate how substrates and protein constituents influence hydrogenase activation, and for the first time, we show that each maturase can function catalytically during the maturation process. With precise control over the biomolecular components, we also provide evidence for H-cluster synthesis in the absence of either HydE or HydF, and we further show that hydrogenase activation can occur without exogenous tyrosine. Given these findings, we suggest a new reaction sequence for the [FeFe] hydrogenase maturation pathway. In our model, HydG independently synthesizes an iron-based compound with CO and CN(-) ligands that is a precursor to the H-cluster [2Fe](H) subunit, and which we have termed HydG-co. We further propose that HydF is a transferase that stabilizes HydG-co and also shuttles the complete [2Fe](H) subcluster to the hydrogenase, a translocation process that may be catalyzed by HydE. In summary, this report describes the first example of reconstructing the [FeFe] hydrogenase maturation pathway using purified maturases and subsequently utilizing this in vitro system to better understand the roles of HydE, HydF, and HydG.
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Affiliation(s)
- Jon M Kuchenreuther
- Department of Chemical Engineering, Stanford University, Stanford, California, USA
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141
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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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142
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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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143
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Jinkerson RE, Radakovits R, Posewitz MC. Genomic insights from the oleaginous model alga Nannochloropsis gaditana. Bioengineered 2012; 4:37-43. [PMID: 22922732 PMCID: PMC3566019 DOI: 10.4161/bioe.21880] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Nannochloropsis species have emerged as leading phototrophic microorganisms for the production of biofuels. Several isolates produce large quantities of triacylglycerols, grow rapidly, and can be cultivated at industrial scales. Recently, the mitochondrial, plastid and nuclear genomes of Nannochloropsis gaditana were sequenced. Genomic interrogation revealed several key features that likely facilitate the oleaginous phenotype observed in Nannochloropsis, including an over-representation of genes involved in lipid biosynthesis. Here we present additional analyses on gene orientation, vitamin B12 requiring enzymes, the acetyl-CoA metabolic node, and codon usage in N. gaditana. Nuclear genome transformation methods are established with exogenous DNA integration occurring via either random incorporation or by homologous recombination, making Nannochloropsis amenable to both forward and reverse genetic engineering. Completion of a draft genomic sequence, establishment of transformation techniques, and robust outdoor growth properties have positioned Nannochloropsis as a new model alga with significant potential for further development into an integrated photons-to-fuel production platform.
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Affiliation(s)
- Robert E Jinkerson
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO, USA
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144
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Atteia A, van Lis R, Tielens AGM, Martin WF. Anaerobic energy metabolism in unicellular photosynthetic eukaryotes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1827:210-23. [PMID: 22902601 DOI: 10.1016/j.bbabio.2012.08.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 07/30/2012] [Accepted: 08/05/2012] [Indexed: 12/25/2022]
Abstract
Anaerobic metabolic pathways allow unicellular organisms to tolerate or colonize anoxic environments. Over the past ten years, genome sequencing projects have brought a new light on the extent of anaerobic metabolism in eukaryotes. A surprising development has been that free-living unicellular algae capable of photoautotrophic lifestyle are, in terms of their enzymatic repertoire, among the best equipped eukaryotes known when it comes to anaerobic energy metabolism. Some of these algae are marine organisms, common in the oceans, others are more typically soil inhabitants. All these species are important from the ecological (O(2)/CO(2) budget), biotechnological, and evolutionary perspectives. In the unicellular algae surveyed here, mixed-acid type fermentations are widespread while anaerobic respiration, which is more typical of eukaryotic heterotrophs, appears to be rare. The presence of a core anaerobic metabolism among the algae provides insights into its evolutionary origin, which traces to the eukaryote common ancestor. The predicted fermentative enzymes often exhibit an amino acid extension at the N-terminus, suggesting that these proteins might be compartmentalized in the cell, likely in the chloroplast or the mitochondrion. The green algae Chlamydomonas reinhardtii and Chlorella NC64 have the most extended set of fermentative enzymes reported so far. Among the eukaryotes with secondary plastids, the diatom Thalassiosira pseudonana has the most pronounced anaerobic capabilities as yet. From the standpoints of genomic, transcriptomic, and biochemical studies, anaerobic energy metabolism in C. reinhardtii remains the best characterized among photosynthetic protists. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems.
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Affiliation(s)
- Ariane Atteia
- Unité de Bioénergétique et Ingénierie des Protéines-UMR 7281, CNRS-Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13402 Marseille, France
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145
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Pape M, Lambertz C, Happe T, Hemschemeier A. Differential expression of the Chlamydomonas [FeFe]-hydrogenase-encoding HYDA1 gene is regulated by the copper response regulator1. PLANT PHYSIOLOGY 2012; 159:1700-12. [PMID: 22669892 PMCID: PMC3425207 DOI: 10.1104/pp.112.200162] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 06/02/2012] [Indexed: 05/20/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii adapts to anaerobic or hypoxic conditions by developing a complex fermentative metabolism including the production of molecular hydrogen by [FeFe]-hydrogenase isoform1 (HYDA1). HYDA1 transcript and hydrogenase protein accumulate in the absence of oxygen or copper (Cu). Factors regulating this differential gene expression have been unknown so far. In this study, we report on the isolation of a Chlamydomonas mutant strain impaired in HYDA1 gene expression by screening an insertional mutagenesis library for HYDA1 promoter activity using the arylsulfatase-encoding ARYLSULFATASE2 gene as a selection marker. The mutant strain has a deletion of the COPPER RESPONSE REGULATOR1 (CRR1) gene encoding for CRR1, indicating that this SQUAMOSA-PROMOTER BINDING PROTEIN (SBP) domain transcription factor is involved in the regulation of HYDA1 transcription. Treating the C. reinhardtii wild type with mercuric ions, which were shown to inhibit the binding of the SBP domain to DNA, prevented or deactivated HYDA1 gene expression. Reporter gene analyses of the HYDA1 promoter revealed that two GTAC motifs, which are known to be the cores of CRR1 binding sites, are necessary for full promoter activity in hypoxic conditions or upon Cu starvation. However, mutations of the GTAC sites had a much stronger impact on reporter gene expression in Cu-deficient cells. Electrophoretic mobility shift assays showed that the CRR1 SBP domain binds to one of the GTAC cores in vitro. These combined results prove that CRR1 is involved in HYDA1 promoter activation.
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146
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Lanz ND, Booker SJ. Identification and function of auxiliary iron-sulfur clusters in radical SAM enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:1196-212. [PMID: 22846545 DOI: 10.1016/j.bbapap.2012.07.009] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/16/2012] [Accepted: 07/17/2012] [Indexed: 11/27/2022]
Abstract
Radical SAM (RS) enzymes use a 5'-deoxyadenosyl 5'-radical generated from a reductive cleavage of S-adenosyl-l-methionine to catalyze over 40 distinct reaction types. A distinguishing feature of these enzymes is a [4Fe-4S] cluster to which each of three iron ions is ligated by three cysteinyl residues most often located in a Cx(3)Cx(2)C motif. The α-amino and α-carboxylate groups of SAM anchor the molecule to the remaining iron ion, which presumably facilitates its reductive cleavage. A subset of RS enzymes contains additional iron-sulfur clusters, - which we term auxiliary clusters - most of which have unidentified functions. Enzymes in this subset are involved in cofactor biosynthesis and maturation, post-transcriptional and post-translational modification, enzyme activation, and antibiotic biosynthesis. The additional clusters in these enzymes have been proposed to function in sulfur donation, electron transfer, and substrate anchoring. This review will highlight evidence supporting the presence of multiple iron-sulfur clusters in these enzymes as well as their predicted roles in catalysis. This article is part of a special issue entitled: Radical SAM enzymes and radical enzymology.
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Affiliation(s)
- Nicholas D Lanz
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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147
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Murthy UMN, Wecker MSA, Posewitz MC, Gilles-Gonzalez MA, Ghirardi ML. Novel FixL homologues in Chlamydomonas reinhardtii bind heme and O(2). FEBS Lett 2012; 586:4282-8. [PMID: 22801216 DOI: 10.1016/j.febslet.2012.06.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 06/26/2012] [Accepted: 06/28/2012] [Indexed: 11/17/2022]
Abstract
Genome inspection revealed nine putative heme-binding, FixL-homologous proteins in Chlamydomonas reinhardtii. The heme-binding domains from two of these proteins, FXL1 and FXL5 were cloned, expressed in Escherichia coli, purified and characterized. The recombinant FXL1 and FXL5 domains stained positively for heme, while mutations in the putative ligand-binding histidine FXL1-H200S and FXL5-H200S resulted in loss of heme binding. The FXL1 and FXL5 [Fe(II), bound O(2)] had Soret absorption maxima around 415 nm, and weaker absorptions at longer wavelengths, in concurrence with the literature. Ligand-binding measurements showed that FXL1 and FXL5 bind O(2) with moderate affinity, 135 and 222 μM, respectively. This suggests that Chlamydomonas may use the FXL proteins in O(2)-sensing mechanisms analogous to that reported in nitrogen-fixing bacteria to regulate gene expression.
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Affiliation(s)
- U M Narayana Murthy
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
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148
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Müller M, Mentel M, van Hellemond JJ, Henze K, Woehle C, Gould SB, Yu RY, van der Giezen M, Tielens AGM, Martin WF. Biochemistry and evolution of anaerobic energy metabolism in eukaryotes. Microbiol Mol Biol Rev 2012; 76:444-95. [PMID: 22688819 PMCID: PMC3372258 DOI: 10.1128/mmbr.05024-11] [Citation(s) in RCA: 498] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Major insights into the phylogenetic distribution, biochemistry, and evolutionary significance of organelles involved in ATP synthesis (energy metabolism) in eukaryotes that thrive in anaerobic environments for all or part of their life cycles have accrued in recent years. All known eukaryotic groups possess an organelle of mitochondrial origin, mapping the origin of mitochondria to the eukaryotic common ancestor, and genome sequence data are rapidly accumulating for eukaryotes that possess anaerobic mitochondria, hydrogenosomes, or mitosomes. Here we review the available biochemical data on the enzymes and pathways that eukaryotes use in anaerobic energy metabolism and summarize the metabolic end products that they generate in their anaerobic habitats, focusing on the biochemical roles that their mitochondria play in anaerobic ATP synthesis. We present metabolic maps of compartmentalized energy metabolism for 16 well-studied species. There are currently no enzymes of core anaerobic energy metabolism that are specific to any of the six eukaryotic supergroup lineages; genes present in one supergroup are also found in at least one other supergroup. The gene distribution across lineages thus reflects the presence of anaerobic energy metabolism in the eukaryote common ancestor and differential loss during the specialization of some lineages to oxic niches, just as oxphos capabilities have been differentially lost in specialization to anoxic niches and the parasitic life-style. Some facultative anaerobes have retained both aerobic and anaerobic pathways. Diversified eukaryotic lineages have retained the same enzymes of anaerobic ATP synthesis, in line with geochemical data indicating low environmental oxygen levels while eukaryotes arose and diversified.
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Affiliation(s)
| | - Marek Mentel
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Jaap J. van Hellemond
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Katrin Henze
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Christian Woehle
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Sven B. Gould
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Re-Young Yu
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Mark van der Giezen
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Aloysius G. M. Tielens
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, Netherlands
| | - William F. Martin
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
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149
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Yacoby I, Tegler LT, Pochekailov S, Zhang S, King PW. Optimized expression and purification for high-activity preparations of algal [FeFe]-hydrogenase. PLoS One 2012; 7:e35886. [PMID: 22563413 PMCID: PMC3338550 DOI: 10.1371/journal.pone.0035886] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Accepted: 03/26/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Recombinant expression and purification of metallo-enzymes, including hydrogenases, at high-yields is challenging due to complex, and enzyme specific, post-translational maturation processes. Low fidelities of maturation result in preparations containing a significant fraction of inactive, apo-protein that are not suitable for biophysical or crystallographic studies. PRINCIPAL FINDINGS We describe the construction, overexpression and high-yield purification of a fusion protein consisting of the algal [2Fe2S]-ferredoxin PetF (Fd) and [FeFe]-hydrogenase HydA1. The maturation of Fd-HydA1 was optimized through improvements in culture conditions and media components used for expression. We also demonstrated that fusion of Fd to the N-terminus of HydA1, in comparison to the C-terminus, led to increased expression levels that were 4-fold higher. Together, these improvements led to enhanced HydA1 activity and improved yield after purification. The strong binding-affinity of Fd for DEAE allowed for two-step purification by ion exchange and StrepTactin affinity chromatography. In addition, the incorporation of a TEV protease site in the Fd-HydA1 linker allowed for the proteolytic removal of Fd after DEAE step, and purification of HydA1 alone by StrepTactin. In combination, this process resulted in HydA1 purification yields of 5 mg L(-1) of culture from E. coli with specific activities of 1000 U (U = 1 µmol hydrogen evolved mg(-1) min(-1)). SIGNIFICANCE The [FeFe]-hydrogenases are highly efficient enzymes and their catalytic sites provide model structures for synthetic efforts to develop robust hydrogen activation catalysts. In order to characterize their structure-function properties in greater detail, and to use hydrogenases for biotechnological applications, reliable methods for rapid, high-yield expression and purification are required.
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Affiliation(s)
- Iftach Yacoby
- Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * E-mail: (IY); (SZ); (PWK)
| | - Lotta Tollstoy Tegler
- Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Sergii Pochekailov
- Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Shuguang Zhang
- Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * E-mail: (IY); (SZ); (PWK)
| | - Paul W. King
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, United States of America
- * E-mail: (IY); (SZ); (PWK)
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150
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Peters JW, Broderick JB. Emerging paradigms for complex iron-sulfur cofactor assembly and insertion. Annu Rev Biochem 2012; 81:429-50. [PMID: 22482905 DOI: 10.1146/annurev-biochem-052610-094911] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
[FeFe]-hydrogenses and molybdenum (Mo)-nitrogenase are evolutionarily unrelated enzymes with unique complex iron-sulfur cofactors at their active sites. The H cluster of [FeFe]-hydrogenases and the FeMo cofactor of Mo-nitrogenase require specific maturation machinery for their proper synthesis and insertion into the structural enzymes. Recent insights reveal striking similarities in the biosynthetic pathways of these complex cofactors. For both systems, simple iron-sulfur cluster precursors are modified on assembly scaffolds by the activity of radical S-adenosylmethionine (SAM) enzymes. Radical SAM enzymes are responsible for the synthesis and insertion of the unique nonprotein ligands presumed to be key structural determinants for their respective catalytic activities. Maturation culminates in the transfer of the intact cluster assemblies to a cofactor-less structural protein recipient. Required roles for nucleotide binding and hydrolysis have been implicated in both systems, but the specific role for these requirements remain unclear. In this review, we highlight the progress on [FeFe]-hydrogenase H cluster and nitrogenase FeMo-cofactor assembly in the context of these emerging paradigms.
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Affiliation(s)
- John W Peters
- Department of Chemistry and Biochemistry and the Astrobiology Biogeocatalysis Research Center, Montana State University, Bozeman, Montana 59717, USA.
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