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Lynes MM, Jay ZJ, Kohtz AJ, Hatzenpichler R. Methylotrophic methanogenesis in the Archaeoglobi revealed by cultivation of Ca. Methanoglobus hypatiae from a Yellowstone hot spring. THE ISME JOURNAL 2024; 18:wrae026. [PMID: 38452205 PMCID: PMC10945360 DOI: 10.1093/ismejo/wrae026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/09/2024] [Accepted: 02/08/2024] [Indexed: 03/09/2024]
Abstract
Over the past decade, environmental metagenomics and polymerase chain reaction-based marker gene surveys have revealed that several lineages beyond just a few well-established groups within the Euryarchaeota superphylum harbor the genetic potential for methanogenesis. One of these groups are the Archaeoglobi, a class of thermophilic Euryarchaeota that have long been considered to live non-methanogenic lifestyles. Here, we enriched Candidatus Methanoglobus hypatiae, a methanogen affiliated with the family Archaeoglobaceae, from a hot spring in Yellowstone National Park. The enrichment is sediment-free, grows at 64-70°C and a pH of 7.8, and produces methane from mono-, di-, and tri-methylamine. Ca. M. hypatiae is represented by a 1.62 Mb metagenome-assembled genome with an estimated completeness of 100% and accounts for up to 67% of cells in the culture according to fluorescence in situ hybridization. Via genome-resolved metatranscriptomics and stable isotope tracing, we demonstrate that Ca. M. hypatiae expresses methylotrophic methanogenesis and energy-conserving pathways for reducing monomethylamine to methane. The detection of Archaeoglobi populations related to Ca. M. hypatiae in 36 geochemically diverse geothermal sites within Yellowstone National Park, as revealed through the examination of previously published gene amplicon datasets, implies a previously underestimated contribution to anaerobic carbon cycling in extreme ecosystems.
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Affiliation(s)
- Mackenzie M Lynes
- Department of Chemistry and Biochemistry, Center for Biofilm Engineering, Thermal Biology Institute, Montana State University, Bozeman, MT 59717, United States
| | - Zackary J Jay
- Department of Chemistry and Biochemistry, Center for Biofilm Engineering, Thermal Biology Institute, Montana State University, Bozeman, MT 59717, United States
| | - Anthony J Kohtz
- Department of Chemistry and Biochemistry, Center for Biofilm Engineering, Thermal Biology Institute, Montana State University, Bozeman, MT 59717, United States
| | - Roland Hatzenpichler
- Department of Chemistry and Biochemistry, Center for Biofilm Engineering, Thermal Biology Institute, Montana State University, Bozeman, MT 59717, United States
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717, United States
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2
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Garritano AN, Song W, Thomas T. Carbon fixation pathways across the bacterial and archaeal tree of life. PNAS NEXUS 2022; 1:pgac226. [PMID: 36712370 PMCID: PMC9802188 DOI: 10.1093/pnasnexus/pgac226] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 10/01/2022] [Indexed: 11/17/2022]
Abstract
Carbon fixation is a critical process for our planet; however, its distribution across the bacterial and archaeal domains of life has not been comprehensively studied. Here, we performed an analysis of 52,515 metagenome-assembled genomes and discover carbon fixation pathways in 1,007 bacteria and archaea. We reveal the genomic potential for carbon fixation through the reverse tricarboxylic acid cycle in previously unrecognized archaeal and bacterial phyla (i.e. Thermoplasmatota and Elusimicrobiota) and show that the 3-hydroxypropionate bi-cycle is not, as previously thought, restricted to the phylum Chloroflexota. The data also substantially expand the phylogenetic breadth for autotrophy through the dicarboxylate/4-hydroxybutyrate cycle and the Calvin-Benson-Bassham cycle. Finally, the genomic potential for carbon fixation through the 3-hydroxypropionate/4-hydroxybutyrate cycle, previously exclusively found in Archaea, was also detected in the Bacteria. Carbon fixation thus appears to be much more widespread than previously known, and this study lays the foundation to better understand the role of archaea and bacteria in global primary production and how they contribute to microbial carbon sinks.
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Affiliation(s)
- Alessandro N Garritano
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, Faculty of Science, The University of New South Wales, Kensington, NSW 2052, Australia
| | - Weizhi Song
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, Faculty of Science, The University of New South Wales, Kensington, NSW 2052, Australia
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3
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Cai M, Duan C, Zhang X, Pan J, Liu Y, Zhang C, Li M. Genomic and transcriptomic dissection of Theionarchaea in marine ecosystem. SCIENCE CHINA. LIFE SCIENCES 2022; 65:1222-1234. [PMID: 34668130 DOI: 10.1007/s11427-021-1996-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 08/17/2021] [Indexed: 11/24/2022]
Abstract
Theionarchaea is a recently described archaeal class within the Euryarchaeota. While it is widely distributed in sediment ecosystems, little is known about its metabolic potential and ecological features. Here, we used metagenomics and metatranscriptomics to characterize 12 theionarchaeal metagenome-assembled genomes, which were further divided into two subgroups, from coastal mangrove sediments of China and seawater columns of the Yap Trench. Genomic analysis revealed that apart from the canonical sulfhydrogenase, Theionarchaea harbor genes encoding heliorhodopsin, group 4 [NiFe]-hydrogenase, and flagellin, in which genes for heliorhodopsin and group 4 [NiFe]-hydrogenase were transcribed in mangrove sediment. Further, the theionarchaeal substrate spectrum may be broader than previously reported as revealed by metagenomics and metatranscriptomics, and the potential carbon substrates include detrital proteins, hemicellulose, ethanol, and CO2. The genes for organic substrate metabolism (mainly detrital protein and amino acid metabolism genes) have relatively higher transcripts in the top sediment layers in mangrove wetlands. In addition, co-occurrence analysis suggested that the degradation of these organic compounds by Theionarchaea might be processed in syntrophy with fermenters (e.g., Chloroflexi) and methanogens. Collectively, these observations expand the current knowledge of the metabolic potential of Theionarchaea, and shed light on the metabolic strategies and roles of these archaea in the marine ecosystems.
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Affiliation(s)
- Mingwei Cai
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Changhai Duan
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, 518060, China
| | - Xinxu Zhang
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Jie Pan
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Yang Liu
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Cuijing Zhang
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Meng Li
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China.
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, 518060, China.
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4
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Welte CU, de Graaf R, Dalcin Martins P, Jansen RS, Jetten MSM, Kurth JM. A novel methoxydotrophic metabolism discovered in the hyperthermophilic archaeon Archaeoglobus fulgidus. Environ Microbiol 2021; 23:4017-4033. [PMID: 33913565 PMCID: PMC8359953 DOI: 10.1111/1462-2920.15546] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/26/2021] [Accepted: 04/26/2021] [Indexed: 11/29/2022]
Abstract
Methoxylated aromatic compounds (MACs) are important components of lignin found in significant amounts in the subsurface. Recently, the methanogenic archaeon Methermicoccus shengliensis was shown to be able to use a variety of MACs during methoxydotrophic growth. After a molecular survey, we found that the hyperthermophilic non‐methanogenic archaeon Archaeoglobus fulgidus also encodes genes for a bacterial‐like demethoxylation system. In this study, we performed growth and metabolite analysis, and used transcriptomics to investigate the response of A. fulgidus during growth on MACs in comparison to growth on lactate. We observed that A. fulgidus converts MACs to their hydroxylated derivatives with CO2 as the main product and sulfate as electron acceptor. Furthermore, we could show that MACs improve the growth of A. fulgidus in the presence of organic substrates such as lactate. We also found evidence that other archaea such as Bathyarchaeota, Lokiarchaeota, Verstraetearchaeota, Korarchaeota, Helarchaeota and Nezhaarchaeota encode a demethoxylation system. In summary, we here describe the first non‐methanogenic archaeon with the ability to grow on MACs indicating that methoxydotrophic archaea might play a so far underestimated role in the global carbon cycle.
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Affiliation(s)
- Cornelia U Welte
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands.,Netherlands Earth System Science Center, Utrecht University, Heidelberglaan 2, Utrecht, 3584 CS, The Netherlands.,Soehngen Institute of Anaerobic Microbiology, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Rob de Graaf
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Paula Dalcin Martins
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Robert S Jansen
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Mike S M Jetten
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands.,Netherlands Earth System Science Center, Utrecht University, Heidelberglaan 2, Utrecht, 3584 CS, The Netherlands.,Soehngen Institute of Anaerobic Microbiology, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Julia M Kurth
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands.,Soehngen Institute of Anaerobic Microbiology, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
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5
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Wrighton KC, Castelle CJ, Varaljay VA, Satagopan S, Brown CT, Wilkins MJ, Thomas BC, Sharon I, Williams KH, Tabita FR, Banfield JF. RubisCO of a nucleoside pathway known from Archaea is found in diverse uncultivated phyla in bacteria. ISME JOURNAL 2016; 10:2702-2714. [PMID: 27137126 PMCID: PMC5113843 DOI: 10.1038/ismej.2016.53] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 02/29/2016] [Accepted: 03/04/2016] [Indexed: 11/23/2022]
Abstract
Metagenomic studies recently uncovered form II/III RubisCO genes, originally thought to only occur in archaea, from uncultivated bacteria of the candidate phyla radiation (CPR). There are no isolated CPR bacteria and these organisms are predicted to have limited metabolic capacities. Here we expand the known diversity of RubisCO from CPR lineages. We report a form of RubisCO, distantly similar to the archaeal form III RubisCO, in some CPR bacteria from the Parcubacteria (OD1), WS6 and Microgenomates (OP11) phyla. In addition, we significantly expand the Peregrinibacteria (PER) II/III RubisCO diversity and report the first II/III RubisCO sequences from the Microgenomates and WS6 phyla. To provide a metabolic context for these RubisCOs, we reconstructed near-complete (>93%) PER genomes and the first closed genome for a WS6 bacterium, for which we propose the phylum name Dojkabacteria. Genomic and bioinformatic analyses suggest that the CPR RubisCOs function in a nucleoside pathway similar to that proposed in Archaea. Detection of form II/III RubisCO and nucleoside metabolism gene transcripts from a PER supports the operation of this pathway in situ. We demonstrate that the PER form II/III RubisCO is catalytically active, fixing CO2 to physiologically complement phototrophic growth in a bacterial photoautotrophic RubisCO deletion strain. We propose that the identification of these RubisCOs across a radiation of obligately fermentative, small-celled organisms hints at a widespread, simple metabolic platform in which ribose may be a prominent currency.
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Affiliation(s)
- Kelly C Wrighton
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | - Cindy J Castelle
- Department of Earth and Planetary Science, UC Berkeley, Berkeley, CA, USA
| | - Vanessa A Varaljay
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | - Sriram Satagopan
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | | | - Michael J Wilkins
- Department of Microbiology, The Ohio State University, Columbus, OH, USA.,School of Earth Sciences, The Ohio State University, Columbus, OH, USA
| | - Brian C Thomas
- Department of Earth and Planetary Science, UC Berkeley, Berkeley, CA, USA
| | - Itai Sharon
- Department of Earth and Planetary Science, UC Berkeley, Berkeley, CA, USA
| | - Kenneth H Williams
- Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - F Robert Tabita
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | - Jillian F Banfield
- Department of Earth and Planetary Science, UC Berkeley, Berkeley, CA, USA.,Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA
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6
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Manzella MP, Holmes DE, Rocheleau JM, Chung A, Reguera G, Kashefi K. The complete genome sequence and emendation of the hyperthermophilic, obligate iron-reducing archaeon "Geoglobus ahangari" strain 234(T). Stand Genomic Sci 2015; 10:77. [PMID: 26457129 PMCID: PMC4600277 DOI: 10.1186/s40793-015-0035-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 07/07/2015] [Indexed: 11/10/2022] Open
Abstract
“Geoglobus ahangari” strain 234T is an obligate Fe(III)-reducing member of the Archaeoglobales, within the archaeal phylum Euryarchaeota, isolated from the Guaymas Basin hydrothermal system. It grows optimally at 88 °C by coupling the reduction of Fe(III) oxides to the oxidation of a wide range of compounds, including long-chain fatty acids, and also grows autotrophically with hydrogen and Fe(III). It is the first archaeon reported to use a direct contact mechanism for Fe(III) oxide reduction, relying on a single archaellum for locomotion, numerous curled extracellular appendages for attachment, and outer-surface heme-containing proteins for electron transfer to the insoluble Fe(III) oxides. Here we describe the annotation of the genome of “G. ahangari” strain 234T and identify components critical to its versatility in electron donor utilization and obligate Fe(III) respiratory metabolism at high temperatures. The genome comprises a single, circular chromosome of 1,770,093 base pairs containing 2034 protein-coding genes and 52 RNA genes. In addition, emended descriptions of the genus “Geoglobus” and species “G. ahangari” are described.
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Affiliation(s)
- Michael P Manzella
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI USA
| | - Dawn E Holmes
- Department of Physical and Biological Sciences, Western New England University, Springfield, MA USA
| | - Jessica M Rocheleau
- Department of Physical and Biological Sciences, Western New England University, Springfield, MA USA
| | - Amanda Chung
- Department of Physical and Biological Sciences, Western New England University, Springfield, MA USA
| | - Gemma Reguera
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI USA
| | - Kazem Kashefi
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI USA
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7
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Kreel NE, Tabita FR. Serine 363 of a Hydrophobic Region of Archaeal Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase from Archaeoglobus fulgidus and Thermococcus kodakaraensis Affects CO2/O2 Substrate Specificity and Oxygen Sensitivity. PLoS One 2015; 10:e0138351. [PMID: 26381513 PMCID: PMC4575112 DOI: 10.1371/journal.pone.0138351] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/28/2015] [Indexed: 11/18/2022] Open
Abstract
Archaeal ribulose 1, 5-bisphospate carboxylase/oxygenase (RubisCO) is differentiated from other RubisCO enzymes and is classified as a form III enzyme, as opposed to the form I and form II RubisCOs typical of chemoautotrophic bacteria and prokaryotic and eukaryotic phototrophs. The form III enzyme from archaea is particularly interesting as several of these proteins exhibit unusual and reversible sensitivity to molecular oxygen, including the enzyme from Archaeoglobus fulgidus. Previous studies with A. fulgidus RbcL2 had shown the importance of Met-295 in oxygen sensitivity and pointed towards the potential significance of another residue (Ser-363) found in a hydrophobic pocket that is conserved in all RubisCO proteins. In the current study, further structure/function studies have been performed focusing on Ser-363 of A. fulgidus RbcL2; various changes in this and other residues of the hydrophobic pocket point to and definitively establish the importance of Ser-363 with respect to interactions with oxygen. In addition, previous findings had indicated discrepant CO2/O2 specificity determinations of the Thermococcus kodakaraensis RubisCO, a close homolog of A. fulgidus RbcL2. It is shown here that the T. kodakaraensis enzyme exhibits a similar substrate specificity as the A. fulgidus enzyme and is also oxygen sensitive, with equivalent residues involved in oxygen interactions.
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Affiliation(s)
- Nathan E. Kreel
- The Ohio State University Biochemistry Program, The Ohio State University, 484 West 12th Avenue, Columbus, Ohio, 43210–1292, United States of America
| | - F. Robert Tabita
- The Ohio State University Biochemistry Program, The Ohio State University, 484 West 12th Avenue, Columbus, Ohio, 43210–1292, United States of America
- Department of Microbiology, The Ohio State University, 484 West 12th Avenue, Columbus, Ohio, 43210–1292, United States of America
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8
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A Post-Genomic View of the Ecophysiology, Catabolism and Biotechnological Relevance of Sulphate-Reducing Prokaryotes. Adv Microb Physiol 2015. [PMID: 26210106 DOI: 10.1016/bs.ampbs.2015.05.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dissimilatory sulphate reduction is the unifying and defining trait of sulphate-reducing prokaryotes (SRP). In their predominant habitats, sulphate-rich marine sediments, SRP have long been recognized to be major players in the carbon and sulphur cycles. Other, more recently appreciated, ecophysiological roles include activity in the deep biosphere, symbiotic relations, syntrophic associations, human microbiome/health and long-distance electron transfer. SRP include a high diversity of organisms, with large nutritional versatility and broad metabolic capacities, including anaerobic degradation of aromatic compounds and hydrocarbons. Elucidation of novel catabolic capacities as well as progress in the understanding of metabolic and regulatory networks, energy metabolism, evolutionary processes and adaptation to changing environmental conditions has greatly benefited from genomics, functional OMICS approaches and advances in genetic accessibility and biochemical studies. Important biotechnological roles of SRP range from (i) wastewater and off gas treatment, (ii) bioremediation of metals and hydrocarbons and (iii) bioelectrochemistry, to undesired impacts such as (iv) souring in oil reservoirs and other environments, and (v) corrosion of iron and concrete. Here we review recent advances in our understanding of SRPs focusing mainly on works published after 2000. The wealth of publications in this period, covering many diverse areas, is a testimony to the large environmental, biogeochemical and technological relevance of these organisms and how much the field has progressed in these years, although many important questions and applications remain to be explored.
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9
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Balsera M, Uberegui E, Schürmann P, Buchanan BB. Evolutionary development of redox regulation in chloroplasts. Antioxid Redox Signal 2014; 21:1327-55. [PMID: 24483204 DOI: 10.1089/ars.2013.5817] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SIGNIFICANCE The post-translational modification of thiol groups stands out as a key strategy that cells employ for metabolic regulation and adaptation to changing environmental conditions. Nowhere is this more evident than in chloroplasts-the O2-evolving photosynthetic organelles of plant cells that are fitted with multiple redox systems, including the thioredoxin (Trx) family of oxidoreductases functional in the reversible modification of regulatory thiols of proteins in all types of cells. The best understood member of this family in chloroplasts is the ferredoxin-linked thioredoxin system (FTS) by which proteins are modified via light-dependent disulfide/dithiol (S-S/2SH) transitions. RECENT ADVANCES Discovered in the reductive activation of enzymes of the Calvin-Benson cycle in illuminated chloroplast preparations, recent studies have extended the role of the FTS far beyond its original boundaries to include a spectrum of cellular processes. Together with the NADP-linked thioredoxin reductase C-type (NTRC) and glutathione/glutaredoxin systems, the FTS also plays a central role in the response of chloroplasts to different types of stress. CRITICAL ISSUES The comparisons of redox regulatory networks functional in chloroplasts of land plants with those of cyanobacteria-prokaryotes considered to be the ancestors of chloroplasts-and different types of algae summarized in this review have provided new insight into the evolutionary development of redox regulation, starting with the simplest O2-evolving organisms. FUTURE DIRECTIONS The evolutionary appearance, mode of action, and specificity of the redox regulatory systems functional in chloroplasts, as well as the types of redox modification operating under diverse environmental conditions stand out as areas for future study.
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Affiliation(s)
- Monica Balsera
- 1 Instituto de Recursos Naturales y Agrobiología de Salamanca , Consejo Superior de Investigaciones Científicas, Salamanca, Spain
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Hocking WP, Stokke R, Roalkvam I, Steen IH. Identification of key components in the energy metabolism of the hyperthermophilic sulfate-reducing archaeon Archaeoglobus fulgidus by transcriptome analyses. Front Microbiol 2014; 5:95. [PMID: 24672515 PMCID: PMC3949148 DOI: 10.3389/fmicb.2014.00095] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 02/20/2014] [Indexed: 11/23/2022] Open
Abstract
Energy conservation via the pathway of dissimilatory sulfate reduction is present in a diverse group of prokaryotes, but is most comprehensively studied in Deltaproteobacteria. In this study, whole-genome microarray analyses were used to provide a model of the energy metabolism of the sulfate-reducing archaeon Archaeoglobus fulgidus, based on comparative analysis of litoautotrophic growth with H2/CO2 and thiosulfate, and heterotrophic growth on lactate with sulfate or thiosulfate. Only 72 genes were expressed differentially between the cultures utilizing sulfate or thiosulfate, whereas 269 genes were affected by a shift in energy source. We identified co-located gene cluster encoding putative lactate dehydrogenases (LDHs; lldD, dld, lldEFG), also present in sulfate-reducing bacteria. These enzymes may take part in energy conservation in A. fulgidus by specifically linking lactate oxidation with APS reduction via the Qmo complex. High transcriptional levels of Fqo confirm an important role of F420H2, as well as a menaquinone-mediated electron transport chain, during heterotrophic growth. A putative periplasmic thiosulfate reductase was identified by specific up-regulation. Also, putative genes for transport of sulfate and sulfite are discussed. We present a model for hydrogen metabolism, based on the probable bifurcation reaction of the Mvh:Hdl hydrogenase, which may inhibit the utilization of Fdred for energy conservation. Energy conservation is probably facilitated via menaquinone to multiple membrane-bound heterodisulfide reductase (Hdr) complexes and the DsrC protein—linking periplasmic hydrogenase (Vht) to the cytoplasmic reduction of sulfite. The ambiguous roles of genes corresponding to fatty acid metabolism induced during growth with H2 are discussed. Putative co-assimilation of organic acids is favored over a homologous secondary carbon fixation pathway, although both mechanisms may contribute to conserve the amount of Fdred needed during autotrophic growth with H2.
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Affiliation(s)
- William P Hocking
- Department of Biology, Centre for Geobiology, University of Bergen Bergen, Norway
| | - Runar Stokke
- Department of Biology, Centre for Geobiology, University of Bergen Bergen, Norway
| | - Irene Roalkvam
- Department of Biology, Centre for Geobiology, University of Bergen Bergen, Norway
| | - Ida H Steen
- Department of Biology, Centre for Geobiology, University of Bergen Bergen, Norway
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11
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Sousa FL, Thiergart T, Landan G, Nelson-Sathi S, Pereira IAC, Allen JF, Lane N, Martin WF. Early bioenergetic evolution. Philos Trans R Soc Lond B Biol Sci 2013; 368:20130088. [PMID: 23754820 PMCID: PMC3685469 DOI: 10.1098/rstb.2013.0088] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Life is the harnessing of chemical energy in such a way that the energy-harnessing device makes a copy of itself. This paper outlines an energetically feasible path from a particular inorganic setting for the origin of life to the first free-living cells. The sources of energy available to early organic synthesis, early evolving systems and early cells stand in the foreground, as do the possible mechanisms of their conversion into harnessable chemical energy for synthetic reactions. With regard to the possible temporal sequence of events, we focus on: (i) alkaline hydrothermal vents as the far-from-equilibrium setting, (ii) the Wood-Ljungdahl (acetyl-CoA) pathway as the route that could have underpinned carbon assimilation for these processes, (iii) biochemical divergence, within the naturally formed inorganic compartments at a hydrothermal mound, of geochemically confined replicating entities with a complexity below that of free-living prokaryotes, and (iv) acetogenesis and methanogenesis as the ancestral forms of carbon and energy metabolism in the first free-living ancestors of the eubacteria and archaebacteria, respectively. In terms of the main evolutionary transitions in early bioenergetic evolution, we focus on: (i) thioester-dependent substrate-level phosphorylations, (ii) harnessing of naturally existing proton gradients at the vent-ocean interface via the ATP synthase, (iii) harnessing of Na(+) gradients generated by H(+)/Na(+) antiporters, (iv) flavin-based bifurcation-dependent gradient generation, and finally (v) quinone-based (and Q-cycle-dependent) proton gradient generation. Of those five transitions, the first four are posited to have taken place at the vent. Ultimately, all of these bioenergetic processes depend, even today, upon CO2 reduction with low-potential ferredoxin (Fd), generated either chemosynthetically or photosynthetically, suggesting a reaction of the type 'reduced iron → reduced carbon' at the beginning of bioenergetic evolution.
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Affiliation(s)
- Filipa L. Sousa
- Institute of Molecular Evolution, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Thorsten Thiergart
- Institute of Molecular Evolution, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Giddy Landan
- Institute of Genomic Microbiology, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Shijulal Nelson-Sathi
- Institute of Molecular Evolution, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Inês A. C. Pereira
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - John F. Allen
- School of Biological and Chemical Sciences, Queen Mary, University of London, London, UK
- Research Department of Genetics, Evolution and Environment, University College London, Gower Street, London, UK
| | - Nick Lane
- Research Department of Genetics, Evolution and Environment, University College London, Gower Street, London, UK
| | - William F. Martin
- Institute of Molecular Evolution, University of Düsseldorf, 40225 Düsseldorf, Germany
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Balsera M, Uberegui E, Susanti D, Schmitz RA, Mukhopadhyay B, Schürmann P, Buchanan BB. Ferredoxin:thioredoxin reductase (FTR) links the regulation of oxygenic photosynthesis to deeply rooted bacteria. PLANTA 2013; 237:619-635. [PMID: 23223880 DOI: 10.1007/s00425-012-1803-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 10/26/2012] [Indexed: 06/01/2023]
Abstract
Uncovered in studies on photosynthesis 35 years ago, redox regulation has been extended to all types of living cells. We understand a great deal about the occurrence, function, and mechanism of action of this mode of regulation, but we know little about its origin and its evolution. To help fill this gap, we have taken advantage of available genome sequences that make it possible to trace the phylogenetic roots of members of the system that was originally described for chloroplasts-ferredoxin, ferredoxin:thioredoxin reductase (FTR), and thioredoxin as well as target enzymes. The results suggest that: (1) the catalytic subunit, FTRc, originated in deeply rooted microaerophilic, chemoautotrophic bacteria where it appears to function in regulating CO(2) fixation by the reverse citric acid cycle; (2) FTRc was incorporated into oxygenic photosynthetic organisms without significant structural change except for addition of a variable subunit (FTRv) seemingly to protect the Fe-S cluster against oxygen; (3) new Trxs and target enzymes were systematically added as evolution proceeded from bacteria through the different types of oxygenic photosynthetic organisms; (4) an oxygenic type of regulation preceded classical light-dark regulation in the regulation of enzymes of CO(2) fixation by the Calvin-Benson cycle; (5) FTR is not universally present in oxygenic photosynthetic organisms, and in certain early representatives is seemingly functionally replaced by NADP-thioredoxin reductase; and (6) FTRc underwent structural diversification to meet the ecological needs of a variety of bacteria and archaea.
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Affiliation(s)
- Monica Balsera
- Instituto de Recursos Naturales y Agrobiología de Salamanca, Salamanca, Spain.
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