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Pavlova ON, Tupikin AE, Chernitsyna SM, Bukin YS, Lomakina AV, Pogodaeva TV, Nikonova AA, Bukin SV, Zemskaya TI, Kabilov MR. Description and Genomic Analysis of the First Facultatively Lithoautotrophic, Thermophilic Bacteria of the Genus Thermaerobacter Isolated from Low-temperature Sediments of Lake Baikal. MICROBIAL ECOLOGY 2023; 86:1604-1619. [PMID: 36717392 DOI: 10.1007/s00248-023-02182-1] [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: 08/06/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Members of the genus Thermaerobacter belong to the phylum Firmicutes and all isolates characterised to date are strictly aerobic and thermophilic. They were isolated from a mud sample of the Challenger Deep in the Mariana Trench, hydrothermal vents, and silt compost. A novel thermophilic, facultatively lithoautotrophic bacteria of the genus Thermaerobacter, strain PB12/4term (=VKM B-3151T), with a metabolism that is uncharacteristic of the type species, was isolated from low-temperature surface sediments near the Posolsk Bank methane seep, Lake Baikal, Russia. The new strain grows with molecular hydrogen as electron donor, elemental sulfur, and thiosulfate as electron acceptors, and CO2/[Formula: see text] as carbon source. The genome of strain PB12/4term consists of one chromosome with a total length of 2.820.915 bp and the G+C content of the genomic DNA was 72.2%. The phylogenomic reconstruction based on 120 conserved bacterial single-copy proteins revealed that strain PB12/4term belongs to the genus Thermaerobacter within in the class Thermaerobacteria, phylum Firmicutes_E. The strain PB12/4term is closely related to Thermaerobacter subterraneus DSM 13965 (ANI=95.08%, AF=0.91) and Thermaerobacter marianensis DSM 12885 (ANI=84.98%, AF=0.77). Genomic and experimental data confirm the ability of the Thermaerobacter PB12/4term pure culture to facultatively lithotrophic growth, which is provided by the presence of [NiFe]hydrogenase enzymes that are absent in T. marianensis DSM 12885 and T. subterraneus DSM 13965. The data obtained on the physiological and biochemical differences of strain PB12/4term provide a deeper insight into the species diversity and functional activity of the genus Thermaerobacter.
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Affiliation(s)
- O N Pavlova
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia.
| | - A E Tupikin
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
| | - S M Chernitsyna
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - Y S Bukin
- Laboratory of Genosystematics, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - A V Lomakina
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - T V Pogodaeva
- Laboratory of Hydrochemistry and Atmosphere Chemistry, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - A A Nikonova
- Laboratory of Chromatography, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - S V Bukin
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - T I Zemskaya
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - M R Kabilov
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
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Magnuson E, Altshuler I, Freyria NJ, Leveille RJ, Whyte LG. Sulfur-cycling chemolithoautotrophic microbial community dominates a cold, anoxic, hypersaline Arctic spring. MICROBIOME 2023; 11:203. [PMID: 37697305 PMCID: PMC10494364 DOI: 10.1186/s40168-023-01628-5] [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: 04/12/2023] [Accepted: 07/19/2023] [Indexed: 09/13/2023]
Abstract
BACKGROUND Gypsum Hill Spring, located in Nunavut in the Canadian High Arctic, is a rare example of a cold saline spring arising through thick permafrost. It perennially discharges cold (~ 7 °C), hypersaline (7-8% salinity), anoxic (~ 0.04 ppm O2), and highly reducing (~ - 430 mV) brines rich in sulfate (2.2 g.L-1) and sulfide (9.5 ppm), making Gypsum Hill an analog to putative sulfate-rich briny habitats on extraterrestrial bodies such as Mars. RESULTS Genome-resolved metagenomics and metatranscriptomics were utilized to describe an active microbial community containing novel metagenome-assembled genomes and dominated by sulfur-cycling Desulfobacterota and Gammaproteobacteria. Sulfate reduction was dominated by hydrogen-oxidizing chemolithoautotrophic Desulfovibrionaceae sp. and was identified in phyla not typically associated with sulfate reduction in novel lineages of Spirochaetota and Bacteroidota. Highly abundant and active sulfur-reducing Desulfuromusa sp. highly transcribed non-coding RNAs associated with transcriptional regulation, showing potential evidence of putative metabolic flexibility in response to substrate availability. Despite low oxygen availability, sulfide oxidation was primarily attributed to aerobic chemolithoautotrophic Halothiobacillaceae. Low abundance and transcription of photoautotrophs indicated sulfur-based chemolithoautotrophy drives primary productivity even during periods of constant illumination. CONCLUSIONS We identified a rare surficial chemolithoautotrophic, sulfur-cycling microbial community active in a unique anoxic, cold, hypersaline Arctic spring. We detected Mars-relevant metabolisms including hydrogenotrophic sulfate reduction, sulfur reduction, and sulfide oxidation, which indicate the potential for microbial life in analogous S-rich brines on past and present Mars. Video Abstract.
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Affiliation(s)
- Elisse Magnuson
- Natural Resource Sciences, McGill University, Ste-Anne-de-Bellevue, QC Canada
| | - Ianina Altshuler
- MACE Laboratory, ALPOLE, School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Nastasia J. Freyria
- Natural Resource Sciences, McGill University, Ste-Anne-de-Bellevue, QC Canada
| | - Richard J. Leveille
- Department of Earth and Planetary Sciences, McGill University, Montreal, QC Canada
- Geosciences Department, John Abbott College, Ste-Anne-de-Bellevue, QC Canada
| | - Lyle G. Whyte
- Natural Resource Sciences, McGill University, Ste-Anne-de-Bellevue, QC Canada
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Vigneron A, Vincent WF, Lovejoy C. Discovery of a novel bacterial class with the capacity to drive sulfur cycling and microbiome structure in a paleo-ocean analog. ISME COMMUNICATIONS 2023; 3:82. [PMID: 37596370 PMCID: PMC10439189 DOI: 10.1038/s43705-023-00287-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 07/21/2023] [Accepted: 07/26/2023] [Indexed: 08/20/2023]
Abstract
Uncultivated microbial taxa represent a large fraction of global microbial diversity and likely drive numerous biogeochemical transformations in natural ecosystems. Geographically isolated, polar ecosystems are complex microbial biomes and refuges of underexplored taxonomic and functional biodiversity. Combining amplicon sequencing with genome-centric metagenomic analysis of samples from one of the world's northernmost lakes (Lake A, Ellesmere Island, Canadian High Arctic), we identified a novel bacterial taxon that dominates in the bottom layer of anoxic, sulfidic, relict sea water that was isolated from the Arctic Ocean some 3000 years ago. Based on phylogenomic comparative analyses, we propose that these bacteria represent a new Class within the poorly described Electryoneota/AABM5-125-24 candidate phylum. This novel class, for which we propose the name Tariuqbacteria, may be either a relict of ancient ocean conditions or endemic to this High Arctic system, provisionally providing a rare example of high-taxonomy level endemism. Consistent with the geochemistry of the bottom water, the genetic composition of the Candidatus Tariuqbacter genome revealed a strictly anaerobic lifestyle with the potential for sulfate and sulfur reduction, a versatile carbon metabolism and the capability to eliminate competing bacteria through methylarsenite production, suggesting an allelochemical influence on microbiome structure by this planktonic microbe.
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Affiliation(s)
- Adrien Vigneron
- Département de Biologie, Université Laval, Québec, QC, Canada.
- Centre d'études nordiques (CEN), Université Laval, Québec, QC, Canada.
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC, Canada.
- Takuvik Joint International Laboratory, Université Laval, Québec, QC, Canada.
| | - Warwick F Vincent
- Département de Biologie, Université Laval, Québec, QC, Canada
- Centre d'études nordiques (CEN), Université Laval, Québec, QC, Canada
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC, Canada
- Takuvik Joint International Laboratory, Université Laval, Québec, QC, Canada
| | - Connie Lovejoy
- Département de Biologie, Université Laval, Québec, QC, Canada
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC, Canada
- Takuvik Joint International Laboratory, Université Laval, Québec, QC, Canada
- Québec Océan, Université Laval, Québec, QC, Canada
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Truong C, Bernard S, Le Pape P, Morin G, Baya C, Merrot P, Gorlas A, Guyot F. Production of carbon-containing pyrite spherules induced by hyperthermophilic Thermococcales: a biosignature? Front Microbiol 2023; 14:1145781. [PMID: 37303784 PMCID: PMC10248028 DOI: 10.3389/fmicb.2023.1145781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Thermococcales, a major order of hyperthermophilic archaea inhabiting iron- and sulfur-rich anaerobic parts of hydrothermal deep-sea vents, are known to induce the formation of iron phosphates, greigite (Fe3S4) and abundant quantities of pyrite (FeS2), including pyrite spherules. In the present study, we report the characterization of the sulfide and phosphate minerals produced in the presence of Thermococcales using X-ray diffraction, synchrotron-based X ray absorption spectroscopy and scanning and transmission electron microscopies. Mixed valence Fe(II)-Fe(III) phosphates are interpreted as resulting from the activity of Thermococcales controlling phosphorus-iron-sulfur dynamics. The pyrite spherules (absent in abiotic control) consist of an assemblage of ultra-small nanocrystals of a few ten nanometers in size, showing coherently diffracting domain sizes of few nanometers. The production of these spherules occurs via a sulfur redox swing from S0 to S-2 and then to S-1, involving a comproportionation of (-II) and (0) oxidation states of sulfur, as supported by S-XANES data. Importantly, these pyrite spherules sequester biogenic organic compounds in small but detectable quantities, possibly making them good biosignatures to be searched for in extreme environments.
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Affiliation(s)
- Chloé Truong
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Sylvain Bernard
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Pierre Le Pape
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Guillaume Morin
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Camille Baya
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Pauline Merrot
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
| | - Aurore Gorlas
- CEA, CNRS, Institute for Integrative Biology of the Cell, Université Paris-Saclay, Gif-sur-Yvette, France
| | - François Guyot
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), MNHN, CNRS, IRD, Sorbonne Université, Paris, France
- Institut Universitaire de France (IUF), Paris, France
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Holden JF, Sistu H. Formate and hydrogen in hydrothermal vents and their use by extremely thermophilic methanogens and heterotrophs. Front Microbiol 2023; 14:1093018. [PMID: 36950162 PMCID: PMC10025317 DOI: 10.3389/fmicb.2023.1093018] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 02/20/2023] [Indexed: 03/08/2023] Open
Abstract
Extremely thermophilic methanogens in the Methanococci and heterotrophs in the Thermococci are common in deep-sea hydrothermal vents. All Methanococci use H2 as an electron donor, and a few species can also use formate. Most Methanococci have a coenzyme F420-reducing formate dehydrogenase. All Thermococci reduce S0 but have hydrogenases and produce H2 in the absence of S0. Some Thermococci have formate hydrogenlyase (Fhl) that reversibly converts H2 and CO2 to formate or an NAD(P)+-reducing formate dehydrogenase (Nfd). Questions remain if Methanococci or Thermococci use or produce formate in nature, why only certain species can grow on or produce formate, and what the physiological role of formate is? Formate forms abiotically in hydrothermal fluids through chemical equilibrium with primarily H2, CO2, and CO and is strongly dependent upon H2 concentration, pH, and temperature. Formate concentrations are highest in hydrothermal fluids where H2 concentrations are also high, such as in ultramafic systems where serpentinization reactions occur. In nature, Methanococci are likely to use formate as an electron donor when H2 is limiting. Thermococci with Fhl likely convert H2 and CO2 to formate when H2 concentrations become inhibitory for growth. They are unlikely to grow on formate in nature unless formate is more abundant than H2 in the environment. Nearly all Methanococci and Thermococci have a gene for at least one formate dehydrogenase catalytic subunit, which may be used to provide free formate for de novo purine biosynthesis. However, only species with a membrane-bound formate transporter can grow on or secrete formate. Interspecies H2 transfer occurs between Thermococci and Methanococci. This and putative interspecies formate transfer may support Methanococci in low H2 environments, which in turn may prevent growth inhibition of Thermococci by its own H2. Future research directions include understanding when, where, and how formate is used and produced by these organisms in nature, and how transcription of Thermococci genes encoding formate-related enzymes are regulated.
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Liang J, Huang H, Wang Y, Li L, Yi J, Wang S. A Cytoplasmic NAD(P)H-Dependent Polysulfide Reductase with Thiosulfate Reductase Activity from the Hyperthermophilic Bacterium Thermotoga maritima. Microbiol Spectr 2022; 10:e0043622. [PMID: 35762779 PMCID: PMC9431562 DOI: 10.1128/spectrum.00436-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/05/2022] [Indexed: 11/22/2022] Open
Abstract
Thermotoga maritima is an anaerobic hyperthermophilic bacterium that efficiently produces H2 by fermenting carbohydrates. High concentration of H2 inhibits the growth of T. maritima, and S0 could eliminate the inhibition and stimulate the growth through its reduction. The mechanism of T. maritima sulfur reduction, however, has not been fully understood. Herein, based on its similarity with archaeal NAD(P)H-dependent sulfur reductases (NSR), the ORF THEMA_RS02810 was identified and expressed in Escherichia coli, and the recombinant protein was characterized. The purified flavoprotein possessed NAD(P)H-dependent S0 reductase activity (1.3 U/mg for NADH and 0.8 U/mg for NADPH), polysulfide reductase activity (0.32 U/mg for NADH and 0.35 U/mg for NADPH), and thiosulfate reductase activity (2.3 U/mg for NADH and 2.5 U/mg for NADPH), which increased 3~4-folds by coenzyme A stimulation. Quantitative RT-PCR analysis showed that nsr was upregulated together with the mbx, yeeE, and rnf genes when the strain grew in S0- or thiosulfate-containing medium. The mechanism for sulfur reduction in T. maritima was discussed, which may affect the redox balance and energy metabolism of T. maritima. Genome search revealed that NSR homolog is widely distributed in thermophilic bacteria and archaea, implying its important role in the sulfur cycle of geothermal environments. IMPORTANCE The reduction of S0 and thiosulfate is essential in the sulfur cycle of geothermal environments, in which thermophiles play an important role. Despite previous research on some sulfur reductases of thermophilic archaea, the mechanism of sulfur reduction in thermophilic bacteria is still not clearly understood. Herein, we confirmed the presence of a cytoplasmic NAD(P)H-dependent polysulfide reductase (NSR) from the hyperthermophile T. maritima, with S0, polysulfide, and thiosulfate reduction activities, in contrast to other sulfur reductases. When grown in S0- or thiosulfate-containing medium, its expression was upregulated. And the putative membrane-bound MBX and Rnf may also play a role in the metabolism, which might influence the redox balance and energy metabolism of T. maritima. This is distinct from the mechanism of sulfur reduction in mesophiles such as Wolinella succinogenes. NSR homologs are widely distributed among heterotrophic thermophiles, suggesting that they may be vital in the sulfur cycle in geothermal environments.
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Affiliation(s)
- Jiyu Liang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, People’s Republic of China
| | - Haiyan Huang
- Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, People’s Republic of China
| | - Yubo Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, People’s Republic of China
| | - Lexin Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, People’s Republic of China
| | - Jihong Yi
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, People’s Republic of China
| | - Shuning Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, People’s Republic of China
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Yu H, Schut GJ, Haja DK, Adams MWW, Li H. Evolution of complex I-like respiratory complexes. J Biol Chem 2021; 296:100740. [PMID: 33957129 PMCID: PMC8165549 DOI: 10.1016/j.jbc.2021.100740] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 04/28/2021] [Accepted: 04/30/2021] [Indexed: 11/06/2022] Open
Abstract
The modern-day respiratory complex I shares a common ancestor with the membrane-bound hydrogenase (MBH) and membrane-bound sulfane sulfur reductase (MBS). MBH and MBS use protons and sulfur as their respective electron sinks, which helped to conserve energy during early life in the Proterozoic era when the Earth's atmosphere was low in oxygen. MBH and MBS likely evolved from an integration of an ancestral, membrane-embedded, multiple resistance and pH antiporter and a soluble redox-active module encompassing a [NiFe] hydrogenase. In this review, we discuss how the structures of MBH, MBS, multiple resistance and pH, photosynthetic NADH dehydrogenase-like complex type-1, and complex I, which have been determined recently, thanks to the advent of high-resolution cryo-EM, have significantly improved our understanding of the catalytic reaction mechanisms and the evolutionary relationships of the respiratory complexes.
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Affiliation(s)
- Hongjun Yu
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Domink K Haja
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA.
| | - Huilin Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, Michigan, USA.
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Vali SW, Haja DK, Brand RA, Adams MWW, Lindahl PA. The Pyrococcus furiosus ironome is dominated by [Fe 4S 4] 2+ clusters or thioferrate-like iron depending on the availability of elemental sulfur. J Biol Chem 2021; 296:100710. [PMID: 33930466 PMCID: PMC8219758 DOI: 10.1016/j.jbc.2021.100710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/12/2021] [Accepted: 04/22/2021] [Indexed: 11/28/2022] Open
Abstract
Pyrococcus furiosus is a hyperthermophilic anaerobic archaeon whose metabolism depends on whether elemental sulfur is (+S0) or is not (-S0) included in growth medium. Under +S0 conditions, expression of respiratory hydrogenase declines while respiratory membrane-bound sulfane reductase and the putative iron-storage protein IssA increase. Our objective was to investigate the iron content of WT and ΔIssA cells under these growth conditions using Mössbauer spectroscopy. WT-S0 cells contained ∼1 mM Fe, with ∼85% present as two spectroscopically distinct forms of S = 0 [Fe4S4]2+ clusters; the remainder was mainly high-spin FeII. WT+S0 cells contained 5 to 9 mM Fe, with 75 to 90% present as magnetically ordered thioferrate-like (TFL) iron nanoparticles. TFL iron was similar to chemically defined thioferrates; both consisted of FeIII ions coordinated by an S4 environment, and both exhibited strong coupling between particles causing high applied fields to have little spectral effect. At high temperatures with magnetic hyperfine interactions abolished, TFL iron exhibited two doublets overlapping those of [Fe4S4]2+ clusters in -S0 cells. This coincidence arose because of similar coordination environments of TFL iron and cluster iron. The TFL structure was more heterogeneous in the presence of IssA. Presented data suggest that IssA may coordinate insoluble iron sulfides as TFL iron, formed as a byproduct of anaerobic sulfur respiration under high iron conditions, which thereby reduces its toxicity to the cell. This was the first Mössbauer characterization of the ironome of an archaeon, and it illustrates differences relative to the iron content of better-studied bacteria such as Escherichia coli.
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Affiliation(s)
- Shaik Waseem Vali
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Dominik K Haja
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Richard A Brand
- Faculty of Physics, University of Duisburg-Essen, Duisburg, Germany; Institute of Nanotechnology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Paul A Lindahl
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA; Department of Chemistry, Texas A&M University, College Station, Texas, USA.
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9
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Patwardhan S, Smedile F, Giovannelli D, Vetriani C. Metaproteogenomic Profiling of Chemosynthetic Microbial Biofilms Reveals Metabolic Flexibility During Colonization of a Shallow-Water Gas Vent. Front Microbiol 2021; 12:638300. [PMID: 33889140 PMCID: PMC8056087 DOI: 10.3389/fmicb.2021.638300] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 03/02/2021] [Indexed: 11/13/2022] Open
Abstract
Tor Caldara is a shallow-water gas vent located in the Mediterranean Sea, with active venting of CO2 and H2S. At Tor Caldara, filamentous microbial biofilms, mainly composed of Epsilon- and Gammaproteobacteria, grow on substrates exposed to the gas venting. In this study, we took a metaproteogenomic approach to identify the metabolic potential and in situ expression of central metabolic pathways at two stages of biofilm maturation. Our findings indicate that inorganic reduced sulfur species are the main electron donors and CO2 the main carbon source for the filamentous biofilms, which conserve energy by oxygen and nitrate respiration, fix dinitrogen gas and detoxify heavy metals. Three metagenome-assembled genomes (MAGs), representative of key members in the biofilm community, were also recovered. Metaproteomic data show that metabolically active chemoautotrophic sulfide-oxidizing members of the Epsilonproteobacteria dominated the young microbial biofilms, while Gammaproteobacteria become prevalent in the established community. The co-expression of different pathways for sulfide oxidation by these two classes of bacteria suggests exposure to different sulfide concentrations within the biofilms, as well as fine-tuned adaptations of the enzymatic complexes. Taken together, our findings demonstrate a shift in the taxonomic composition and associated metabolic activity of these biofilms in the course of the colonization process.
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Affiliation(s)
- Sushmita Patwardhan
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, United States
| | - Francesco Smedile
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, United States.,National Research Council, Institute for Coastal Marine Environment, Messina, Italy
| | - Donato Giovannelli
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, United States.,Department of Biology, University of Naples "Federico II," Naples, Italy.,National Research Council, Institute for Marine Biological and Biotechnological Resources, Ancona, Italy.,Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Costantino Vetriani
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, United States.,Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, United States
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Abstract
Mobile genetic elements (MGEs) often encode integrases which catalyze the site-specific insertion of their genetic information into the host genome and the reverse reaction of excision. Hyperthermophilic archaea harbor integrases belonging to the SSV-family which carry the MGE recombination site within their open reading frame. Upon integration into the host genome, SSV integrases disrupt their own gene into two inactive pseudogenes and are termed suicidal for this reason. The evolutionary maintenance of suicidal integrases, concurring with the high prevalence and multiples recruitments of these recombinases by archaeal MGEs, is highly paradoxical. To elucidate this phenomenon, we analyzed the wide phylogenomic distribution of a prominent class of suicidal integrases which revealed a highly variable integration site specificity. Our results highlighted the remarkable hybrid nature of these enzymes encoded from the assembly of inactive pseudogenes of different origins. The characterization of the biological properties of one of these integrases, IntpT26-2 showed that this enzyme was active over a wide range of temperatures up to 99 °C and displayed a less-stringent site specificity requirement than comparable integrases. These observations concurred in explaining the pervasiveness of these suicidal integrases in the most hyperthermophilic organisms. The biochemical and phylogenomic data presented here revealed a target site switching system operating on highly thermostable integrases and suggested a new model for split gene reconstitution. By generating fast-evolving pseudogenes at high frequency, suicidal integrases constitute a powerful model to approach the molecular mechanisms involved in the generation of active genes variants by the recombination of proto-genes.
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Affiliation(s)
- Catherine Badel
- Microbiology Department, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, University of Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Violette Da Cunha
- Microbiology Department, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, University of Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Patrick Forterre
- Microbiology Department, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, University of Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France.,Unité de Biologie Moléculaire du Gène chez les Extrêmophiles, Département de Microbiologie, Institut Pasteur, Paris, France
| | - Jacques Oberto
- Microbiology Department, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, University of Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
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Yu H, Haja DK, Schut GJ, Wu CH, Meng X, Zhao G, Li H, Adams MWW. Structure of the respiratory MBS complex reveals iron-sulfur cluster catalyzed sulfane sulfur reduction in ancient life. Nat Commun 2020; 11:5953. [PMID: 33230146 PMCID: PMC7684303 DOI: 10.1038/s41467-020-19697-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/19/2020] [Indexed: 11/17/2022] Open
Abstract
Modern day aerobic respiration in mitochondria involving complex I converts redox energy into chemical energy and likely evolved from a simple anaerobic system now represented by hydrogen gas-evolving hydrogenase (MBH) where protons are the terminal electron acceptor. Here we present the cryo-EM structure of an early ancestor in the evolution of complex I, the elemental sulfur (S0)-reducing reductase MBS. Three highly conserved protein loops linking cytoplasmic and membrane domains enable scalable energy conversion in all three complexes. MBS contains two proton pumps compared to one in MBH and likely conserves twice the energy. The structure also reveals evolutionary adaptations of MBH that enabled S0 reduction by MBS catalyzed by a site-differentiated iron-sulfur cluster without participation of protons or amino acid residues. This is the simplest mechanism proposed for reduction of inorganic or organic disulfides. It is of fundamental significance in the iron and sulfur-rich volcanic environments of early earth and possibly the origin of life. MBS provides a new perspective on the evolution of modern-day respiratory complexes and of catalysis by biological iron-sulfur clusters. The sulfur-reducing enzyme MBS and the hydrogen-gas evolving MBH are the evolutionary link between the ancestor Mrp antiporter and the mitochondrial respiratory complex I. Here, the authors characterise MBS from the hyperthermophilic archaeon Pyrococcus furiosus, solve its cryo-EM structure and discuss the structural evolution from Mrp to MBH and MBS and to the modern-day complex I.
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Affiliation(s)
- Hongjun Yu
- Structural Biology Program, Van Andel Institute, Grand Rapids, MI, USA.,Department of Biochemistry and Molecular Biology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dominik K Haja
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Chang-Hao Wu
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Xing Meng
- Structural Biology Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Gongpu Zhao
- Structural Biology Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Huilin Li
- Structural Biology Program, Van Andel Institute, Grand Rapids, MI, USA.
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA.
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12
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Zhao W, Ma X, Liu X, Jian H, Zhang Y, Xiao X. Cross-Stress Adaptation in a Piezophilic and Hyperthermophilic Archaeon From Deep Sea Hydrothermal Vent. Front Microbiol 2020; 11:2081. [PMID: 33013758 PMCID: PMC7511516 DOI: 10.3389/fmicb.2020.02081] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/07/2020] [Indexed: 11/13/2022] Open
Abstract
Hyperthermophiles, living in environments above 80°C and usually coupling with multi-extreme environmental stresses, have drawn great attention due to their application potential in biotechnology and being the primitive extant forms of life. Studies on their survival and adaptation mechanisms have extended our understanding on how lives thrive under extreme conditions. During these studies, the "cross-stress" behavior in various organisms has been observed between the extreme high temperature and other environmental stresses. Despite the broad observation, the global view of the cross-stress behavior remains unclear in hyperthermophiles, leaving a knowledge gap in our understanding of extreme adaptation. In this study, we performed a global quantitative proteomic analysis under extreme temperatures, pH, hydrostatic pressure (HP), and salinity on an archaeal strain, Thermococcus eurythermalis A501, which has outstanding growth capability on a wide range of temperatures (50-100°C), pH (4-9), and HPs (0.1-70 MPa), but a narrow range of NaCl (1.0-5.0 %, w/v). The proteomic analysis (79.8% genome coverage) demonstrated that approximately 61.5% of the significant differentially expressed proteins (DEPs) responded to multiple stresses. The responses to most of the tested stresses were closely correlated, except the responses to high salinity and low temperature. The top three enriched universal responding processes include the biosynthesis and protection of macromolecules, biosynthesis and metabolism of amino acids, ion transport, and binding activities. In addition, this study also revealed that the specific dual-stress responding processes, such as the membrane lipids for both cold and HP stresses and the signal transduction for both hyperosmotic and heat stresses, as well as the sodium-dependent energetic processes might be the limiting factor of the growth range in salinity. The present study is the first to examine the global cross-stress responses in a piezophilic hyperthermophile at the proteomic level. Our findings provide direct evidences of the cross-stress adaptation strategy (33.5% of coding-genes) to multiple stresses and highlight the specific and unique responding processes (0.22-0.63% of coding genes for each) to extreme temperature, pH, salinity, and pressure, which are highly relevant to the fields of evolutionary biology as well as next generation industrial biotechnology (NGIB).
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Affiliation(s)
- Weishu Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaopan Ma
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaoxia Liu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Huahua Jian
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yu Zhang
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiang Xiao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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13
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Metabolic Adaptation to Sulfur of Hyperthermophilic Palaeococcus pacificus DY20341 T from Deep-Sea Hydrothermal Sediments. Int J Mol Sci 2020; 21:ijms21010368. [PMID: 31935923 PMCID: PMC6981617 DOI: 10.3390/ijms21010368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 12/26/2019] [Accepted: 12/29/2019] [Indexed: 11/30/2022] Open
Abstract
The hyperthermo-piezophilic archaeon Palaeococcus pacificus DY20341T, isolated from East Pacific hydrothermal sediments, can utilize elemental sulfur as a terminal acceptor to simulate growth. To gain insight into sulfur metabolism, we performed a genomic and transcriptional analysis of Pa. pacificus DY20341T with/without elemental sulfur as an electron acceptor. In the 2001 protein-coding sequences of the genome, transcriptomic analysis showed that 108 genes increased (by up to 75.1 fold) and 336 genes decreased (by up to 13.9 fold) in the presence of elemental sulfur. Palaeococcus pacificus cultured with elemental sulfur promoted the following: the induction of membrane-bound hydrogenase (MBX), NADH:polysulfide oxidoreductase (NPSOR), NAD(P)H sulfur oxidoreductase (Nsr), sulfide dehydrogenase (SuDH), connected to the sulfur-reducing process, the upregulation of iron and nickel/cobalt transfer, iron–sulfur cluster-carrying proteins (NBP35), and some iron–sulfur cluster-containing proteins (SipA, SAM, CobQ, etc.). The accumulation of metal ions might further impact on regulators, e.g., SurR and TrmB. For growth in proteinous media without elemental sulfur, cells promoted flagelin, peptide/amino acids transporters, and maltose/sugar transporters to upregulate protein and starch/sugar utilization processes and riboflavin and thiamin biosynthesis. This indicates how strain DY20341T can adapt to different living conditions with/without elemental sulfur in the hydrothermal fields.
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14
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Slobodkin A, Slobodkina G, Allioux M, Alain K, Jebbar M, Shadrin V, Kublanov I, Toshchakov S, Bonch-Osmolovskaya E. Genomic Insights into the Carbon and Energy Metabolism of a Thermophilic Deep-Sea Bacterium Deferribacter autotrophicus Revealed New Metabolic Traits in the Phylum Deferribacteres. Genes (Basel) 2019; 10:genes10110849. [PMID: 31717820 PMCID: PMC6896113 DOI: 10.3390/genes10110849] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 01/12/2023] Open
Abstract
Information on the biochemical pathways of carbon and energy metabolism in representatives of the deep lineage bacterial phylum Deferribacteres are scarce. Here, we report the results of the sequencing and analysis of the high-quality draft genome of the thermophilic chemolithoautotrophic anaerobe Deferribacter autotrophicus. Genomic data suggest that CO2 assimilation is carried out by recently proposed reversible tricarboxylic acid cycle (“roTCA cycle”). The predicted genomic ability of D. autotrophicus to grow due to the oxidation of carbon monoxide was experimentally proven. CO oxidation was coupled with the reduction of nitrate to ammonium. Utilization of CO most likely involves anaerobic [Ni, Fe]-containing CO dehydrogenase. This is the first evidence of CO oxidation in the phylum Deferribacteres. The genome of D. autotrophicus encodes a Nap-type complex of nitrate reduction. However, the conversion of produced nitrite to ammonium proceeds via a non-canonical pathway with the participation of hydroxylamine oxidoreductase (Hao) and hydroxylamine reductase. The genome contains 17 genes of putative multiheme c-type cytochromes and “e-pilin” genes, some of which are probably involved in Fe(III) reduction. Genomic analysis indicates that the roTCA cycle of CO2 fixation and putative Hao-enabled ammonification may occur in several members of the phylum Deferribacteres.
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Affiliation(s)
- Alexander Slobodkin
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (G.S.); (V.S.); (I.K.); (S.T.); (E.B.-O.)
- Correspondence:
| | - Galina Slobodkina
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (G.S.); (V.S.); (I.K.); (S.T.); (E.B.-O.)
| | - Maxime Allioux
- Univ Brest, CNRS, Ifremer, LIA1211, Laboratoire de Microbiologie des Environnements Extrêmes LM2E, F-29280 Plouzané, France; (M.A.); (K.A.); (M.J.)
| | - Karine Alain
- Univ Brest, CNRS, Ifremer, LIA1211, Laboratoire de Microbiologie des Environnements Extrêmes LM2E, F-29280 Plouzané, France; (M.A.); (K.A.); (M.J.)
| | - Mohamed Jebbar
- Univ Brest, CNRS, Ifremer, LIA1211, Laboratoire de Microbiologie des Environnements Extrêmes LM2E, F-29280 Plouzané, France; (M.A.); (K.A.); (M.J.)
| | - Valerian Shadrin
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (G.S.); (V.S.); (I.K.); (S.T.); (E.B.-O.)
| | - Ilya Kublanov
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (G.S.); (V.S.); (I.K.); (S.T.); (E.B.-O.)
| | - Stepan Toshchakov
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (G.S.); (V.S.); (I.K.); (S.T.); (E.B.-O.)
| | - Elizaveta Bonch-Osmolovskaya
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (G.S.); (V.S.); (I.K.); (S.T.); (E.B.-O.)
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15
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Hackley RK, Schmid AK. Global Transcriptional Programs in Archaea Share Features with the Eukaryotic Environmental Stress Response. J Mol Biol 2019; 431:4147-4166. [PMID: 31437442 PMCID: PMC7419163 DOI: 10.1016/j.jmb.2019.07.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 07/18/2019] [Accepted: 07/18/2019] [Indexed: 01/06/2023]
Abstract
The environmental stress response (ESR), a global transcriptional program originally identified in yeast, is characterized by a rapid and transient transcriptional response composed of large, oppositely regulated gene clusters. Genes induced during the ESR encode core components of stress tolerance, macromolecular repair, and maintenance of homeostasis. In this review, we investigate the possibility for conservation of the ESR across the eukaryotic and archaeal domains of life. We first re-analyze existing transcriptomics data sets to illustrate that a similar transcriptional response is identifiable in Halobacterium salinarum, an archaeal model organism. To substantiate the archaeal ESR, we calculated gene-by-gene correlations, gene function enrichment, and comparison of temporal dynamics. We note reported examples of variation in the ESR across fungi, then synthesize high-level trends present in expression data of other archaeal species. In particular, we emphasize the need for additional high-throughput time series expression data to further characterize stress-responsive transcriptional programs in the Archaea. Together, this review explores an open question regarding features of global transcriptional stress response programs shared across domains of life.
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Affiliation(s)
- Rylee K Hackley
- Department of Biology, Duke University, Durham, NC 27708, USA; University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA
| | - Amy K Schmid
- Department of Biology, Duke University, Durham, NC 27708, USA; University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA; Center for Genomics and Computational Biology, Duke University, Durham, NC 27708, USA.
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16
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Characterization of thiosulfate reductase from Pyrobaculum aerophilum heterologously produced in Pyrococcus furiosus. Extremophiles 2019; 24:53-62. [PMID: 31278423 DOI: 10.1007/s00792-019-01112-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 06/26/2019] [Indexed: 10/26/2022]
Abstract
The genome of the archaeon Pyrobaculum aerophilum (Topt ~ 100 °C) contains an operon (PAE2859-2861) encoding a putative pyranopterin-containing oxidoreductase of unknown function and metal content. These genes (with one gene modified to encode a His-affinity tag) were inserted into the fermentative anaerobic archaeon, Pyrococcus furiosus (Topt ~ 100 °C). Dye-linked assays of cytoplasmic extracts from recombinant P. furiosus show that the P. aerophilum enzyme is a thiosulfate reductase (Tsr) and reduces thiosulfate but not polysulfide. The enzyme (Tsr-Mo) from molybdenum-grown cells contains Mo (Mo:W = 9:1) while the enzyme (Tsr-W) from tungsten-grown cells contains mainly W (Mo:W = 1:6). Purified Tsr-Mo has over ten times the activity (Vmax = 1580 vs. 141 µmol min-1 mg-1) and twice the affinity for thiosulfate (Km = ~ 100 vs. ~ 200 μM) than Tsr-W and is reduced at a lower potential (Epeak = - 255 vs - 402 mV). Tsr-Mo and Tsr-W proteins are heterodimers lacking the membrane anchor subunit (PAE2861). Recombinant P. furiosus expressing P. aerophilum Tsr could not use thiosulfate as a terminal electron acceptor. P. furiosus contains five pyranopterin-containing enzymes, all of which utilize W. P. aerophilum Tsr-Mo is the first example of an active Mo-containing enzyme produced in P. furiosus.
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17
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Distinct Physiological Roles of the Three Ferredoxins Encoded in the Hyperthermophilic Archaeon Thermococcus kodakarensis. mBio 2019; 10:mBio.02807-18. [PMID: 30837343 PMCID: PMC6401487 DOI: 10.1128/mbio.02807-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
High-energy electrons liberated during catabolic processes can be exploited for energy-conserving mechanisms. Maximal energy gains demand these valuable electrons be accurately shuttled from electron donor to appropriate electron acceptor. Proteinaceous electron carriers such as ferredoxins offer opportunities to exploit specific ferredoxin partnerships to ensure that electron flux to critical physiological pathways is aligned with maximal energy gains. Most species encode many ferredoxin isoforms, but very little is known about the role of individual ferredoxins in most systems. Our results detail that ferredoxin isoforms make largely unique and distinct protein interactions in vivo and that flux through one ferredoxin often cannot be recovered by flux through a different ferredoxin isoform. The results obtained more broadly suggest that ferredoxin isoforms throughout biological life have evolved not as generic electron shuttles, but rather serve as selective couriers of valuable low-potential electrons from select electron donors to desirable electron acceptors. Control of electron flux is critical in both natural and bioengineered systems to maximize energy gains. Both small molecules and proteins shuttle high-energy, low-potential electrons liberated during catabolism through diverse metabolic landscapes. Ferredoxin (Fd) proteins—an abundant class of Fe-S-containing small proteins—are essential in many species for energy conservation and ATP production strategies. It remains difficult to model electron flow through complicated metabolisms and in systems in which multiple Fd proteins are present. The overlap of activity and/or limitations of electron flux through each Fd can limit physiology and metabolic engineering strategies. Here we establish the interplay, reactivity, and physiological role(s) of the three ferredoxin proteins in the model hyperthermophile Thermococcus kodakarensis. We demonstrate that the three loci encoding known Fds are subject to distinct regulatory mechanisms and that specific Fds are utilized to shuttle electrons to separate respiratory and energy production complexes during different physiological states. The results obtained argue that unique physiological roles have been established for each Fd and that continued use of T. kodakarensis and related hydrogen-evolving species as bioengineering platforms must account for the distinct Fd partnerships that limit flux to desired electron acceptors. Extrapolating our results more broadly, the retention of multiple Fd isoforms in most species argues that specialized Fd partnerships are likely to influence electron flux throughout biology.
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18
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A review of the mechanisms of mineral-based metabolism in early Earth analog rock-hosted hydrothermal ecosystems. World J Microbiol Biotechnol 2019; 35:29. [PMID: 30689069 DOI: 10.1007/s11274-019-2604-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 01/20/2019] [Indexed: 10/27/2022]
Abstract
Prior to the advent of oxygenic photosynthesis ~ 2.8-3.2 Ga, life was dependent on chemical energy captured from oxidation-reduction reactions involving minerals or substrates generated through interaction of water with minerals. Terrestrial hydrothermal environments host abundant and diverse non-photosynthetic communities and a variety of minerals that can sustain microbial metabolism. Minerals and substrates generated through interaction of minerals with water are differentially distributed in hot spring environments which, in turn, shapes the distribution of microbial life and the metabolic processes that support it. Emerging evidence suggests that terrestrial hydrothermal environments may have played a role in supporting the metabolism of the earliest forms of microbial life. It follows that these environments and their microbial inhabitants are increasingly being studied as analogs of early Earth ecosystems. Here we review current understanding of the processes that lead to variation in the availability of minerals or mineral-sourced substrates in terrestrial hydrothermal environments. In addition, we summarize proposed mechanisms of mineral substrate acquisition and metabolism in microbial cells inhabiting terrestrial hydrothermal environments, highlighting the importance of the dynamic interplay between biotic and abiotic reactions in influencing mineral substrate bioavailability. An emphasis is placed on mechanisms involved in the solubilization, acquisition, and metabolism of sulfur- and iron-bearing minerals, since these elements were likely integrated into the metabolism of the earliest anaerobic cells.
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19
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Hydrogen-based metabolism as an ancestral trait in lineages sibling to the Cyanobacteria. Nat Commun 2019; 10:463. [PMID: 30692531 PMCID: PMC6349859 DOI: 10.1038/s41467-018-08246-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 12/18/2018] [Indexed: 01/06/2023] Open
Abstract
The evolution of aerobic respiration was likely linked to the origins of oxygenic Cyanobacteria. Close phylogenetic neighbors to Cyanobacteria, such as Margulisbacteria (RBX-1 and ZB3), Saganbacteria (WOR-1), Melainabacteria and Sericytochromatia, may constrain the metabolic platform in which aerobic respiration arose. Here, we analyze genomic sequences and predict that sediment-associated Margulisbacteria have a fermentation-based metabolism featuring a variety of hydrogenases, a streamlined nitrogenase, and electron bifurcating complexes involved in cycling of reducing equivalents. The genomes of ocean-associated Margulisbacteria encode an electron transport chain that may support aerobic growth. Some Saganbacteria genomes encode various hydrogenases, and others may be able to use O2 under certain conditions via a putative novel type of heme copper O2 reductase. Similarly, Melainabacteria have diverse energy metabolisms and are capable of fermentation and aerobic or anaerobic respiration. The ancestor of all these groups may have been an anaerobe in which fermentation and H2 metabolism were central metabolic features. The ability to use O2 as a terminal electron acceptor must have been subsequently acquired by these lineages. Most cyanobacteria are oxygenic photoautotrophs, and fermenters under dark anoxic conditions. Here, the authors analyse genomic sequences of related uncultivated bacteria, inferring their metabolic potential, and supporting that their common ancestor was an anaerobe capable of fermentation and H2 metabolism.
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20
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Martinez MA, Woodcroft BJ, Ignacio Espinoza JC, Zayed AA, Singleton CM, Boyd JA, Li YF, Purvine S, Maughan H, Hodgkins SB, Anderson D, Sederholm M, Temperton B, Bolduc B, Saleska SR, Tyson GW, Rich VI, Saleska SR, Tyson GW, Rich VI. Discovery and ecogenomic context of a global Caldiserica-related phylum active in thawing permafrost, Candidatus Cryosericota phylum nov., Ca. Cryosericia class nov., Ca. Cryosericales ord. nov., Ca. Cryosericaceae fam. nov., comprising the four species Cryosericum septentrionale gen. nov. sp. nov., Ca. C. hinesii sp. nov., Ca. C. odellii sp. nov., Ca. C. terrychapinii sp. nov. Syst Appl Microbiol 2019; 42:54-66. [DOI: 10.1016/j.syapm.2018.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 12/05/2018] [Accepted: 12/05/2018] [Indexed: 10/27/2022]
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21
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Straub CT, Counts JA, Nguyen DMN, Wu CH, Zeldes BM, Crosby JR, Conway JM, Otten JK, Lipscomb GL, Schut GJ, Adams MWW, Kelly RM. Biotechnology of extremely thermophilic archaea. FEMS Microbiol Rev 2018; 42:543-578. [PMID: 29945179 DOI: 10.1093/femsre/fuy012] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Accepted: 06/23/2018] [Indexed: 12/26/2022] Open
Abstract
Although the extremely thermophilic archaea (Topt ≥ 70°C) may be the most primitive extant forms of life, they have been studied to a limited extent relative to mesophilic microorganisms. Many of these organisms have unique biochemical and physiological characteristics with important biotechnological implications. These include methanogens that generate methane, fermentative anaerobes that produce hydrogen gas with high efficiency, and acidophiles that can mobilize base, precious and strategic metals from mineral ores. Extremely thermophilic archaea have also been a valuable source of thermoactive, thermostable biocatalysts, but their use as cellular systems has been limited because of the general lack of facile genetics tools. This situation has changed recently, however, thereby providing an important avenue for understanding their metabolic and physiological details and also opening up opportunities for metabolic engineering efforts. Along these lines, extremely thermophilic archaea have recently been engineered to produce a variety of alcohols and industrial chemicals, in some cases incorporating CO2 into the final product. There are barriers and challenges to these organisms reaching their full potential as industrial microorganisms but, if these can be overcome, a new dimension for biotechnology will be forthcoming that strategically exploits biology at high temperatures.
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Affiliation(s)
- Christopher T Straub
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - James A Counts
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Diep M N Nguyen
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Chang-Hao Wu
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Benjamin M Zeldes
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - James R Crosby
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Jonathan M Conway
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Jonathan K Otten
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Gina L Lipscomb
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology University of Georgia, Athens, GA 30602, USA
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
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22
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Conserved principles of transcriptional networks controlling metabolic flexibility in archaea. Emerg Top Life Sci 2018; 2:659-669. [PMID: 33525832 PMCID: PMC7289023 DOI: 10.1042/etls20180036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/05/2018] [Accepted: 11/08/2018] [Indexed: 12/13/2022]
Abstract
Gene regulation is intimately connected with metabolism, enabling the appropriate timing and tuning of biochemical pathways to substrate availability. In microorganisms, such as archaea and bacteria, transcription factors (TFs) often directly sense external cues such as nutrient substrates, metabolic intermediates, or redox status to regulate gene expression. Intense recent interest has characterized the functions of a large number of such regulatory TFs in archaea, which regulate a diverse array of unique archaeal metabolic capabilities. However, it remains unclear how the co-ordinated activity of the interconnected metabolic and transcription networks produces the dynamic flexibility so frequently observed in archaeal cells as they respond to energy limitation and intermittent substrate availability. In this review, we communicate the current state of the art regarding these archaeal networks and their dynamic properties. We compare the topology of these archaeal networks to those known for bacteria to highlight conserved and unique aspects. We present a new computational model for an exemplar archaeal network, aiming to lay the groundwork toward understanding general principles that unify the dynamic function of integrated metabolic-transcription networks across archaea and bacteria.
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23
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Wu CH, Schut GJ, Poole FL, Haja DK, Adams MWW. Characterization of membrane-bound sulfane reductase: A missing link in the evolution of modern day respiratory complexes. J Biol Chem 2018; 293:16687-16696. [PMID: 30181217 DOI: 10.1074/jbc.ra118.005092] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 08/30/2018] [Indexed: 11/06/2022] Open
Abstract
Hyperthermophilic archaea contain a hydrogen gas-evolving,respiratory membrane-bound NiFe-hydrogenase (MBH) that is very closely related to the aerobic respiratory complex I. During growth on elemental sulfur (S°), these microorganisms also produce a homologous membrane-bound complex (MBX), which generates H2S. MBX evolutionarily links MBH to complex I, but its catalytic function is unknown. Herein, we show that MBX reduces the sulfane sulfur of polysulfides by using ferredoxin (Fd) as the electron donor, and we rename it membrane-bound sulfane reductase (MBS). Two forms of affinity-tagged MBS were purified from genetically engineered Pyrococcus furiosus (a hyperthermophilic archaea species): the 13-subunit holoenzyme (S-MBS) and a cytoplasmic 4-subunit catalytic subcomplex (C-MBS). S-MBS and C-MBS reduced dimethyl trisulfide (DMTS) with comparable Km (∼490 μm) and V max values (12 μmol/min/mg). The MBS catalytic subunit (MbsL), but not that of complex I (NuoD), retains two of four NiFe-coordinating cysteine residues of MBH. However, these cysteine residues were not involved in MBS catalysis because a mutant P. furiosus strain (MbsLC85A/C385A) grew normally with S°. The products of the DMTS reduction and properties of polysulfides indicated that in the physiological reaction, MBS uses Fd (E o' = -480 mV) to reduce sulfane sulfur (E o' -260 mV) and cleave organic (RS n R, n ≥ 3) and anionic polysulfides (S n 2-, n ≥ 4) but that it does not produce H2S. Based on homology to MBH, MBS also creates an ion gradient for ATP synthesis. This work establishes the electrochemical reaction catalyzed by MBS that is intermediate in the evolution from proton- to quinone-reducing respiratory complexes.
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Affiliation(s)
- Chang-Hao Wu
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Gerrit J Schut
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Farris L Poole
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Dominik K Haja
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Michael W W Adams
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
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24
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Jelen B, Giovannelli D, Falkowski PG, Vetriani C. Elemental sulfur reduction in the deep‐sea vent thermophile,
Thermovibrio ammonificans. Environ Microbiol 2018; 20:2301-2316. [DOI: 10.1111/1462-2920.14280] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 05/10/2018] [Accepted: 05/12/2018] [Indexed: 01/20/2023]
Affiliation(s)
- Benjamin Jelen
- Environmental Biophysics and Molecular Ecology Program Rutgers University, New Brunswick New Brunswick NJ 08901 USA
| | - Donato Giovannelli
- Department of Marine and Coastal Sciences Rutgers University New Brunswick NJ 08901 USA
- Institute of Marine Science National Research Council Ancona 60125 Italy
- Earth‐Life Science Institute Tokyo Institute of Technology Tokyo 152‐8550 Japan
| | - Paul G. Falkowski
- Environmental Biophysics and Molecular Ecology Program Rutgers University, New Brunswick New Brunswick NJ 08901 USA
- Department of Marine and Coastal Sciences Rutgers University New Brunswick NJ 08901 USA
- Department of Earth and Planetary Sciences Rutgers University New Brunswick NJ 08854 USA
| | - Costantino Vetriani
- Department of Marine and Coastal Sciences Rutgers University New Brunswick NJ 08901 USA
- Department of Biochemistry and Microbiology Rutgers University New Brunswick NJ 08901 USA
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25
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Sea K, Lee J, To D, Chen B, Sazinsky MH, Crane EJ. A broader active site in Pyrococcus horikoshii CoA disulfide reductase accommodates larger substrates and reveals evidence of subunit asymmetry. FEBS Open Bio 2018; 8:1083-1092. [PMID: 29988575 PMCID: PMC6026696 DOI: 10.1002/2211-5463.12439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 02/07/2018] [Accepted: 04/25/2018] [Indexed: 12/03/2022] Open
Abstract
Within the family of pyridine nucleotide disulfide oxidoreductase (PNDOR), enzymes are a group of single‐cysteine containing FAD‐dependent reductases that utilize a tightly bound coenzyme A to assist in the NAD(P)H‐dependent reduction of di‐, per‐, and polysulfide substrates in bacteria and archaea. For many of these homodimeric enzymes, it has proved difficult to determine the substrate specificity and metabolic function based on sequence and genome analysis alone. Coenzyme A‐disulfide reductase (CoADR) isolated from Pyrococcus horikoshii (phCoADR) reduces Co‐A per‐ and polysulfides, but, unlike other highly homologous members of this group, is a poor CoA disulfide reductase. The phCoADR structure has a narrower access channel for CoA substrates, which suggested that this restriction might be responsible for the enzyme's poor activity toward the bulky CoA disulfide substrate. To test this hypothesis, the substrate channel was widened by making four mutations along the channel wall (Y65A, Y66A, P67G, and H367G). The structure of the quadruple mutant shows a widened substrate channel, which is supported by a fourfold increase in kcat for the NAD(P)H‐dependent reduction of CoA disulfide and enhanced activity toward the substrate at lower temperatures. Anaerobic titrations of the enzyme with NADH revealed a half‐site reactivity not observed with the wild‐type enzyme in which one subunit of the enzyme could be fully reduced to an EH4 state, while the other remained in an EH2 or EH2·NADH state. These results suggest that for these closely related enzymes, substrate channel morphology is an important determinant of substrate specificity, and homology modeling will be the preferred technique for predicting function among PNDORs.
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Affiliation(s)
- Kevin Sea
- Department of Chemistry Pomona College Claremont CA USA.,Department of Wine Studies Santa Rosa Junior College CA USA
| | - Jerry Lee
- Department of Biology Pomona College Claremont CA USA
| | - Daniel To
- Department of Chemistry Pomona College Claremont CA USA
| | - Berniece Chen
- Department of Chemistry Pomona College Claremont CA USA
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26
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Marques Netto CGC, Palmeira DJ, Brondani PB, Andrade LH. Enzymatic reactions involving the heteroatoms from organic substrates. AN ACAD BRAS CIENC 2018; 90:943-992. [PMID: 29742205 DOI: 10.1590/0001-3765201820170741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/01/2018] [Indexed: 11/22/2022] Open
Abstract
Several enzymatic reactions of heteroatom-containing compounds have been explored as unnatural substrates. Considerable advances related to the search for efficient enzymatic systems able to support a broader substrate scope with high catalytic performance are described in the literature. These reports include mainly native and mutated enzymes and whole cells biocatalysis. Herein, we describe the historical background along with the progress of biocatalyzed reactions involving the heteroatom(S, Se, B, P and Si) from hetero-organic substrates.
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Affiliation(s)
| | - Dayvson J Palmeira
- Departamento de Química Fundamental, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Patrícia B Brondani
- Departamento de Ciências Exatas e Educação, Universidade Federal de Santa Catarina, Blumenau, SC, Brazil
| | - Leandro H Andrade
- Departamento de Química Fundamental, Universidade de São Paulo, São Paulo, SP, Brazil
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27
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Martin WF, Bryant DA, Beatty JT. A physiological perspective on the origin and evolution of photosynthesis. FEMS Microbiol Rev 2018; 42:205-231. [PMID: 29177446 PMCID: PMC5972617 DOI: 10.1093/femsre/fux056] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/20/2017] [Indexed: 12/22/2022] Open
Abstract
The origin and early evolution of photosynthesis are reviewed from an ecophysiological perspective. Earth's first ecosystems were chemotrophic, fueled by geological H2 at hydrothermal vents and, required flavin-based electron bifurcation to reduce ferredoxin for CO2 fixation. Chlorophyll-based phototrophy (chlorophototrophy) allowed autotrophs to generate reduced ferredoxin without electron bifurcation, providing them access to reductants other than H2. Because high-intensity, short-wavelength electromagnetic radiation at Earth's surface would have been damaging for the first chlorophyll (Chl)-containing cells, photosynthesis probably arose at hydrothermal vents under low-intensity, long-wavelength geothermal light. The first photochemically active pigments were possibly Zn-tetrapyrroles. We suggest that (i) after the evolution of red-absorbing Chl-like pigments, the first light-driven electron transport chains reduced ferredoxin via a type-1 reaction center (RC) progenitor with electrons from H2S; (ii) photothioautotrophy, first with one RC and then with two, was the bridge between H2-dependent chemolithoautotrophy and water-splitting photosynthesis; (iii) photothiotrophy sustained primary production in the photic zone of Archean oceans; (iv) photosynthesis arose in an anoxygenic cyanobacterial progenitor; (v) Chl a is the ancestral Chl; and (vi), anoxygenic chlorophototrophic lineages characterized so far acquired, by horizontal gene transfer, RCs and Chl biosynthesis with or without autotrophy, from the architects of chlorophototrophy-the cyanobacterial lineage.
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Affiliation(s)
- William F Martin
- Institute for Molecular Evolution, University of Düsseldorf, D-40225 Düsseldorf, Germany
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - J Thomas Beatty
- Department of Microbiology and Immunology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
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28
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Searcy DG. Elemental sulfur reduction to H 2S by Tetrahymena thermophila. Eur J Protistol 2017; 62:56-68. [PMID: 29248819 DOI: 10.1016/j.ejop.2017.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 11/22/2017] [Accepted: 11/24/2017] [Indexed: 11/19/2022]
Abstract
Eukaryotic nucleocytoplasm is believed to be descended from ancient Archaea that respired on elemental sulfur. If so, a vestige of sulfur reduction might persist in modern eukaryotic cells. That was tested in Tetrahymena thermophila, chosen as a model organism. When oxygenated, the cells consumed H2S rapidly, but when made anoxic they produced H2S mostly by amino acid catabolism. That could be inhibited by adding aminooxyacetic acid, and then H2S production from elemental sulfur became more evident. Anoxic cell lysates produced H2S when provided with sulfur and NADH, but not with either substrate alone. When lysates were fractionated by centrifugation, NADH-dependent H2S production was 83% in the soluble fraction. When intact cells that had just previously oxidized H2S were shifted to anoxia, the cells produced H2S evidently by re-using the oxidized sulfur. After aerobic H2S oxidation was stopped, the oxidation product remained available for H2S production for about 10 min. The observed H2S production is consistent with an evolutionary relationship of nucleocytoplasm to sulfur-reducing Archaea. Mitochondria often are the cellular site of H2S oxidation, suggesting that eukaryotic cells might have evolved from an ancient symbiosis that was based upon sulfur exchange.
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Affiliation(s)
- Dennis G Searcy
- Biology Department, University of Massachusetts, Amherst, MA 01003, USA.
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29
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Vaccaro BJ, Clarkson SM, Holden JF, Lee DW, Wu CH, Poole Ii FL, Cotelesage JJH, Hackett MJ, Mohebbi S, Sun J, Li H, Johnson MK, George GN, Adams MWW. Biological iron-sulfur storage in a thioferrate-protein nanoparticle. Nat Commun 2017; 8:16110. [PMID: 28726794 PMCID: PMC5524996 DOI: 10.1038/ncomms16110] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 05/30/2017] [Indexed: 11/09/2022] Open
Abstract
Iron–sulfur clusters are ubiquitous in biology and function in electron transfer and catalysis. They are assembled from iron and cysteine sulfur on protein scaffolds. Iron is typically stored as iron oxyhydroxide, ferrihydrite, encapsulated in 12 nm shells of ferritin, which buffers cellular iron availability. Here we have characterized IssA, a protein that stores iron and sulfur as thioferrate, an inorganic anionic polymer previously unknown in biology. IssA forms nanoparticles reaching 300 nm in diameter and is the largest natural metalloprotein complex known. It is a member of a widely distributed protein family that includes nitrogenase maturation factors, NifB and NifX. IssA nanoparticles are visible by electron microscopy as electron-dense bodies in the cytoplasm. Purified nanoparticles appear to be generated from 20 nm units containing ∼6,400 Fe atoms and ∼170 IssA monomers. In support of roles in both iron–sulfur storage and cluster biosynthesis, IssA reconstitutes the [4Fe-4S] cluster in ferredoxin in vitro. The biosynthesis of iron-sulfur clusters in anaerobic organisms has not been extensively investigated. Here, the authors identify and characterize a multi-subunit protein that stores iron and sulfur in thioferrate for the assembly of the clusters in Pyrococcus furiosus.
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Affiliation(s)
- Brian J Vaccaro
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Sonya M Clarkson
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - James F Holden
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Dong-Woo Lee
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Chang-Hao Wu
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Farris L Poole Ii
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Julien J H Cotelesage
- Department of Geological Sciences and Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C5, Canada
| | - Mark J Hackett
- Department of Geological Sciences and Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C5, Canada
| | - Sahel Mohebbi
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Jingchuan Sun
- Cryo-EM Structural Biology Laboratory, Center for Epigenetics, Van Andel Research Institute, Grand Rapids, Michigan 49503, USA
| | - Huilin Li
- Cryo-EM Structural Biology Laboratory, Center for Epigenetics, Van Andel Research Institute, Grand Rapids, Michigan 49503, USA
| | - Michael K Johnson
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Graham N George
- Department of Geological Sciences and Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C5, Canada
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
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30
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Nguyen DMN, Schut GJ, Zadvornyy OA, Tokmina-Lukaszewska M, Poudel S, Lipscomb GL, Adams LA, Dinsmore JT, Nixon WJ, Boyd ES, Bothner B, Peters JW, Adams MWW. Two functionally distinct NADP +-dependent ferredoxin oxidoreductases maintain the primary redox balance of Pyrococcus furiosus. J Biol Chem 2017; 292:14603-14616. [PMID: 28705933 DOI: 10.1074/jbc.m117.794172] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/10/2017] [Indexed: 01/08/2023] Open
Abstract
Electron bifurcation has recently gained acceptance as the third mechanism of energy conservation in which energy is conserved through the coupling of exergonic and endergonic reactions. A structure-based mechanism of bifurcation has been elucidated recently for the flavin-based enzyme NADH-dependent ferredoxin NADP+ oxidoreductase I (NfnI) from the hyperthermophillic archaeon Pyrococcus furiosus. NfnI is thought to be involved in maintaining the cellular redox balance, producing NADPH for biosynthesis by recycling the two other primary redox carriers, NADH and ferredoxin. The P. furiosus genome encodes an NfnI paralog termed NfnII, and the two are differentially expressed, depending on the growth conditions. In this study, we show that deletion of the genes encoding either NfnI or NfnII affects the cellular concentrations of NAD(P)H and particularly NADPH. This results in a moderate to severe growth phenotype in deletion mutants, demonstrating a key role for each enzyme in maintaining redox homeostasis. Despite their similarity in primary sequence and cofactor content, crystallographic, kinetic, and mass spectrometry analyses reveal that there are fundamental structural differences between the two enzymes, and NfnII does not catalyze the NfnI bifurcating reaction. Instead, it exhibits non-bifurcating ferredoxin NADP oxidoreductase-type activity. NfnII is therefore proposed to be a bifunctional enzyme and also to catalyze a bifurcating reaction, although its third substrate, in addition to ferredoxin and NADP(H), is as yet unknown.
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Affiliation(s)
- Diep M N Nguyen
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Gerrit J Schut
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Oleg A Zadvornyy
- the Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164, and
| | | | - Saroj Poudel
- Microbiology and Immunology, Montana State University, Bozeman, Montana 59717
| | - Gina L Lipscomb
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Leslie A Adams
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Jessica T Dinsmore
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - William J Nixon
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Eric S Boyd
- Microbiology and Immunology, Montana State University, Bozeman, Montana 59717
| | | | - John W Peters
- the Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164, and
| | - Michael W W Adams
- From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602,
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31
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Giovannelli D, Sievert SM, Hügler M, Markert S, Becher D, Schweder T, Vetriani C. Insight into the evolution of microbial metabolism from the deep-branching bacterium, Thermovibrio ammonificans. eLife 2017; 6. [PMID: 28436819 PMCID: PMC5441870 DOI: 10.7554/elife.18990] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 04/23/2017] [Indexed: 01/10/2023] Open
Abstract
Anaerobic thermophiles inhabit relic environments that resemble the early Earth. However, the lineage of these modern organisms co-evolved with our planet. Hence, these organisms carry both ancestral and acquired genes and serve as models to reconstruct early metabolism. Based on comparative genomic and proteomic analyses, we identified two distinct groups of genes in Thermovibrio ammonificans: the first codes for enzymes that do not require oxygen and use substrates of geothermal origin; the second appears to be a more recent acquisition, and may reflect adaptations to cope with the rise of oxygen on Earth. We propose that the ancestor of the Aquificae was originally a hydrogen oxidizing, sulfur reducing bacterium that used a hybrid pathway for CO2 fixation. With the gradual rise of oxygen in the atmosphere, more efficient terminal electron acceptors became available and this lineage acquired genes that increased its metabolic flexibility while retaining ancestral metabolic traits. DOI:http://dx.doi.org/10.7554/eLife.18990.001 Life may have arisen on our planet as far back as four billion years ago. Unlike today, the Earth’s atmosphere at the time had no oxygen and an abundance of volcanic emissions including hydrogen, carbon dioxide and sulfur gases. These dramatic differences have led scientists to wonder: how did the ancient microorganisms that inhabited our early planet make a living? And how has microbial life co-evolved with the Earth? One way to answer these questions is to study bacteria that live today in environments that resemble the early Earth. Deep-sea hydrothermal vents are regions of the deep ocean where active volcanic processes recreate primordial conditions. These habitats support microorganisms that are highly adapted to live off hydrogen, carbon dioxide and sulfur gases, and studying these modern-day microorganisms could give insights into the earliest life on Earth. Thermovibrio ammonificans is a bacterium that was obtained from an underwater volcanic system in the East Pacific. Giovannelli et al. have now asked if T. ammonificans might have inherited some of its genetic traits from a long-gone ancestor that also thrived off volcanic gases. The genetic makeup of this microorganism was examined for genes that would help it thrive at a deep-sea hydrothermal vent. Next, Giovannelli et al. compared these genes to related copies in other species of bacteria to reconstruct how the metabolism of T. ammonificans might have changed over time. This approach identified a group of likely ancient genesthat allow a microorganism to use chemicals like hydrogen, carbon dioxide and sulfur to fuel its growth and metabolism. These findings support the hypothesis that an ancestor of T. ammonificans could live off volcanic gases and that the core set of genes involved in those activities had been passed on, through the generations, to this modern-day microorganism. Giovannelli et al. also identified a second group of genes in T. ammonificans that indicate that this bacterium also co-evolved with Earth’s changing conditions, in particular the rise in the concentration of oxygen. The findings of Giovannelli et al. provide insight into how the metabolism of microbes has co-evolved with the Earth’s changing conditions, and will allow others to formulate new hypotheses that can be tested in laboratory experiments. DOI:http://dx.doi.org/10.7554/eLife.18990.002
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Affiliation(s)
- Donato Giovannelli
- Institute of Earth, Ocean and Atmospheric Sciences, Rutgers University, New Brunswick, United States.,Institute of Marine Science, National Research Council of Italy, Ancona, Italy.,Program in Interdisciplinary Studies, Institute for Advanced Studies, Princeton, United States.,Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Stefan M Sievert
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, United States
| | | | - Stephanie Markert
- Pharmaceutical Biotechnology, Institute of Pharmacy, Institute of Pharmacy, Ernst-Moritz-Arndt-University Greifswald, Greifswald, Germany
| | - Dörte Becher
- Institute for Microbiology, Ernst-Moritz-Arndt-University Greifswald, Greifswald, Germany
| | - Thomas Schweder
- Pharmaceutical Biotechnology, Institute of Pharmacy, Institute of Pharmacy, Ernst-Moritz-Arndt-University Greifswald, Greifswald, Germany
| | - Costantino Vetriani
- Institute of Earth, Ocean and Atmospheric Sciences, Rutgers University, New Brunswick, United States.,Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, United States
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32
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Lipscomb GL, Schut GJ, Scott RA, Adams MWW. SurR is a master regulator of the primary electron flow pathways in the order Thermococcales. Mol Microbiol 2017; 104:869-881. [PMID: 28295726 DOI: 10.1111/mmi.13668] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2017] [Indexed: 11/29/2022]
Abstract
The sulfur response regulator, SurR, is among a handful of known redox-active transcriptional regulators. First characterized from the hyperthermophile Pyrococcus furiosus, it is unique to the archaeal order Thermococcales. P. furiosus has two modes of electron disposal. Hydrogen gas is produced when the organism is grown in the absence of elemental sulfur (S0 ) and H2 S is produced when grown in its presence. Switching between these metabolic modes requires a rapid transcriptional response and this is orchestrated by SurR. We show here that deletion of SurR causes severely impaired growth in the absence of S0 since genes essential for H2 metabolism are no longer activated. Conversely, a strain containing a constitutively active SurR variant displays a growth phenotype in the presence of S0 due to constitutive repression of S0 -responsive genes. During a metabolic shift initiated by addition of S0 to the growth medium, both strains demonstrate a de-regulation of genes involved in the SurR regulon, including hydrogenase and related S0 -responsive genes. These results demonstrate that SurR is a master regulator of electron flow within P. furiosus, likely affecting the pools of ferredoxin, NADPH and NADH, as well as influencing metabolic pathways and thiol/disulfide redox balance.
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Affiliation(s)
- Gina L Lipscomb
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Gerrit J Schut
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Robert A Scott
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
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33
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Lim JK, Jung HC, Kang SG, Lee HS. Redox regulation of SurR by protein disulfide oxidoreductase in Thermococcus onnurineus NA1. Extremophiles 2017; 21:491-498. [PMID: 28251348 DOI: 10.1007/s00792-017-0919-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/13/2017] [Indexed: 01/22/2023]
Abstract
Protein disulfide oxidoreductases are redox enzymes that catalyze thiol-disulfide exchange reactions. These enzymes include thioredoxins, glutaredoxins, protein disulfide isomerases, disulfide bond formation A (DsbA) proteins, and Pyrococcus furiosus protein disulfide oxidoreductase (PfPDO) homologues. In the genome of a hyperthermophilic archaeon, Thermococcus onnurineus NA1, the genes encoding one PfPDO homologue (TON_0319, Pdo) and three more thioredoxin- or glutaredoxin-like proteins (TON_0470, TON_0472, TON_0834) were identified. All except TON_0470 were recombinantly expressed and purified. Three purified proteins were reduced by a thioredoxin reductase (TrxR), indicating that each protein can form redox complex with TrxR. SurR, a transcription factor involved in the sulfur response, was tested for a protein target of a TrxR-redoxin system and only Pdo was identified to be capable of catalyzing the reduction of SurR. Electromobility shift assay demonstrated that SurR reduced by the TrxR-Pdo system could bind to the DNA probe with the SurR-binding motif, GTTttgAAC. In this study, we present the TrxR-Pdo couple as a redox-regulator for SurR in T. onnurineus NA1.
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Affiliation(s)
- Jae Kyu Lim
- Marine Biotechnology Research Division, Korea Institute of Ocean Science and Technology, Ansan, 15627, Republic of Korea.,Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Hae-Chang Jung
- Marine Biotechnology Research Division, Korea Institute of Ocean Science and Technology, Ansan, 15627, Republic of Korea.,Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Sung Gyun Kang
- Marine Biotechnology Research Division, Korea Institute of Ocean Science and Technology, Ansan, 15627, Republic of Korea. .,Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea.
| | - Hyun Sook Lee
- Marine Biotechnology Research Division, Korea Institute of Ocean Science and Technology, Ansan, 15627, Republic of Korea. .,Department of Marine Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea.
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34
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Counts JA, Zeldes BM, Lee LL, Straub CT, Adams MWW, Kelly RM. Physiological, metabolic and biotechnological features of extremely thermophilic microorganisms. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2017; 9. [PMID: 28206708 DOI: 10.1002/wsbm.1377] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 11/23/2016] [Accepted: 11/30/2016] [Indexed: 12/12/2022]
Abstract
The current upper thermal limit for life as we know it is approximately 120°C. Microorganisms that grow optimally at temperatures of 75°C and above are usually referred to as 'extreme thermophiles' and include both bacteria and archaea. For over a century, there has been great scientific curiosity in the basic tenets that support life in thermal biotopes on earth and potentially on other solar bodies. Extreme thermophiles can be aerobes, anaerobes, autotrophs, heterotrophs, or chemolithotrophs, and are found in diverse environments including shallow marine fissures, deep sea hydrothermal vents, terrestrial hot springs-basically, anywhere there is hot water. Initial efforts to study extreme thermophiles faced challenges with their isolation from difficult to access locales, problems with their cultivation in laboratories, and lack of molecular tools. Fortunately, because of their relatively small genomes, many extreme thermophiles were among the first organisms to be sequenced, thereby opening up the application of systems biology-based methods to probe their unique physiological, metabolic and biotechnological features. The bacterial genera Caldicellulosiruptor, Thermotoga and Thermus, and the archaea belonging to the orders Thermococcales and Sulfolobales, are among the most studied extreme thermophiles to date. The recent emergence of genetic tools for many of these organisms provides the opportunity to move beyond basic discovery and manipulation to biotechnologically relevant applications of metabolic engineering. WIREs Syst Biol Med 2017, 9:e1377. doi: 10.1002/wsbm.1377 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- James A Counts
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Benjamin M Zeldes
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Laura L Lee
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Christopher T Straub
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
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Loder AJ, Zeldes BM, Conway JM, Counts JA, Straub CT, Khatibi PA, Lee LL, Vitko NP, Keller MW, Rhaesa AM, Rubinstein GM, Scott IM, Lipscomb GL, Adams MW, Kelly RM. Extreme Thermophiles as Metabolic Engineering Platforms: Strategies and Current Perspective. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807796.ch14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Andrew J. Loder
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Benjamin M. Zeldes
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Jonathan M. Conway
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - James A. Counts
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Christopher T. Straub
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Piyum A. Khatibi
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Laura L. Lee
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Nicholas P. Vitko
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Matthew W. Keller
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Amanda M. Rhaesa
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Gabe M. Rubinstein
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Israel M. Scott
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Gina L. Lipscomb
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Michael W.W. Adams
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Robert M. Kelly
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
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Kozhevnikova DA, Taranov EA, Lebedinsky AV, Bonch-Osmolovskaya EA, Sokolova TG. Hydrogenogenic and sulfidogenic growth of Thermococcus archaea on carbon monoxide and formate. Microbiology (Reading) 2016. [DOI: 10.1134/s0026261716040135] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Michoud G, Jebbar M. High hydrostatic pressure adaptive strategies in an obligate piezophile Pyrococcus yayanosii. Sci Rep 2016; 6:27289. [PMID: 27250364 PMCID: PMC4890121 DOI: 10.1038/srep27289] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 05/14/2016] [Indexed: 02/06/2023] Open
Abstract
Pyrococcus yayanosii CH1, as the first and only obligate piezophilic hyperthermophilic microorganism discovered to date, extends the physical and chemical limits of life on Earth. It was isolated from the Ashadze hydrothermal vent at 4,100 m depth. Multi-omics analyses were performed to study the mechanisms used by the cell to cope with high hydrostatic pressure variations. In silico analyses showed that the P. yayanosii genome is highly adapted to its harsh environment, with a loss of aromatic amino acid biosynthesis pathways and the high constitutive expression of the energy metabolism compared with other non-obligate piezophilic Pyrococcus species. Differential proteomics and transcriptomics analyses identified key hydrostatic pressure-responsive genes involved in translation, chemotaxis, energy metabolism (hydrogenases and formate metabolism) and Clustered Regularly Interspaced Short Palindromic Repeats sequences associated with Cellular apoptosis susceptibility proteins.
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Affiliation(s)
- Grégoire Michoud
- Univ Brest, CNRS, Ifremer, UMR 6197-Laboratoire de Microbiologie des Environnements Extrêmes (LM2E), Institut Universitaire Européen de la Mer (IUEM), rue Dumont d'Urville, 29 280 Plouzané, France
| | - Mohamed Jebbar
- Univ Brest, CNRS, Ifremer, UMR 6197-Laboratoire de Microbiologie des Environnements Extrêmes (LM2E), Institut Universitaire Européen de la Mer (IUEM), rue Dumont d'Urville, 29 280 Plouzané, France
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The Proteome and Lipidome of Thermococcus kodakarensis across the Stationary Phase. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2016; 2016:5938289. [PMID: 27274708 PMCID: PMC4870337 DOI: 10.1155/2016/5938289] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/07/2016] [Indexed: 12/25/2022]
Abstract
The majority of cells in nature probably exist in a stationary-phase-like state, due to nutrient limitation in most environments. Studies on bacteria and yeast reveal morphological and physiological changes throughout the stationary phase, which lead to an increased ability to survive prolonged nutrient limitation. However, there is little information on archaeal stationary phase responses. We investigated protein- and lipid-level changes in Thermococcus kodakarensis with extended time in the stationary phase. Adaptations to time in stationary phase included increased proportion of membrane lipids with a tetraether backbone, synthesis of proteins that ensure translational fidelity, specific regulation of ABC transporters (upregulation of some, downregulation of others), and upregulation of proteins involved in coenzyme production. Given that the biological mechanism of tetraether synthesis is unknown, we also considered whether any of the protein-level changes in T. kodakarensis might shed light on the production of tetraether lipids across the same period. A putative carbon-nitrogen hydrolase, a TldE (a protease in Escherichia coli) homologue, and a membrane bound hydrogenase complex subunit were candidates for possible involvement in tetraether-related reactions, while upregulation of adenosylcobalamin synthesis proteins might lend support to a possible radical mechanism as a trigger for tetraether synthesis.
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Analysis of the complete genome sequence of the archaeon Pyrococcus chitonophagus DSM 10152 (formerly Thermococcus chitonophagus). Extremophiles 2016; 20:351-61. [DOI: 10.1007/s00792-016-0826-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/15/2016] [Indexed: 10/22/2022]
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Adaptive engineering of a hyperthermophilic archaeon on CO and discovering the underlying mechanism by multi-omics analysis. Sci Rep 2016; 6:22896. [PMID: 26975345 PMCID: PMC4791640 DOI: 10.1038/srep22896] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/23/2016] [Indexed: 01/03/2023] Open
Abstract
The hyperthermophilic archaeon Thermococcus onnurineus NA1 can grow and produce H2 on carbon monoxide (CO) and its H2 production rates have been improved through metabolic engineering. In this study, we applied adaptive evolution to enhance H2 productivity. After over 150 serial transfers onto CO medium, cell density, CO consumption rate and H2 production rate increased. The underlying mechanism for those physiological changes could be explained by using multi-omics approaches including genomic, transcriptomic and epigenomic analyses. A putative transcriptional regulator was newly identified to regulate the expression levels of genes related to CO oxidation. Transcriptome analysis revealed significant changes in the transcript levels of genes belonging to the categories of transcription, translation and energy metabolism. Our study presents the first genome-scale methylation pattern of hyperthermophilic archaea. Adaptive evolution led to highly enhanced H2 productivity at high CO flow rates using synthesis gas produced from coal gasification.
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Baker BJ, Saw JH, Lind AE, Lazar CS, Hinrichs KU, Teske AP, Ettema TJG. Genomic inference of the metabolism of cosmopolitan subsurface Archaea, Hadesarchaea. Nat Microbiol 2016; 1:16002. [PMID: 27572167 DOI: 10.1038/nmicrobiol.2016.2] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/08/2016] [Indexed: 11/09/2022]
Abstract
The subsurface biosphere is largely unexplored and contains a broad diversity of uncultured microbes(1). Despite being one of the few prokaryotic lineages that is cosmopolitan in both the terrestrial and marine subsurface(2-4), the physiological and ecological roles of SAGMEG (South-African Gold Mine Miscellaneous Euryarchaeal Group) Archaea are unknown. Here, we report the metabolic capabilities of this enigmatic group as inferred from genomic reconstructions. Four high-quality (63-90% complete) genomes were obtained from White Oak River estuary and Yellowstone National Park hot spring sediment metagenomes. Phylogenomic analyses place SAGMEG Archaea as a deeply rooting sister clade of the Thermococci, leading us to propose the name Hadesarchaea for this new Archaeal class. With an estimated genome size of around 1.5 Mbp, the genomes of Hadesarchaea are distinctly streamlined, yet metabolically versatile. They share several physiological mechanisms with strict anaerobic Euryarchaeota. Several metabolic characteristics make them successful in the subsurface, including genes involved in CO and H2 oxidation (or H2 production), with potential coupling to nitrite reduction to ammonia (DNRA). This first glimpse into the metabolic capabilities of these cosmopolitan Archaea suggests they are mediating key geochemical processes and are specialized for survival in the subsurface biosphere.
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Affiliation(s)
- Brett J Baker
- Department of Marine Science, University of Texas Austin, Marine Science Institute, Port Aransas, Texas 78373, USA
| | - Jimmy H Saw
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Anders E Lind
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
| | - Cassandre Sara Lazar
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Kai-Uwe Hinrichs
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Andreas P Teske
- Department of Marine Sciences, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden
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Tao Y, Hu X, Zhu X, Jin H, Xu Z, Tang Q, Li X. Production of Butyrate from Lactate by a Newly Isolated Clostridium sp. BPY5. Appl Biochem Biotechnol 2016; 179:361-74. [DOI: 10.1007/s12010-016-1999-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 01/24/2016] [Indexed: 10/22/2022]
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Choi AR, Kim MS, Kang SG, Lee HS. Dimethyl sulfoxide reduction by a hyperhermophilic archaeon Thermococcus onnurineus NA1 via a cysteine-cystine redox shuttle. J Microbiol 2016; 54:31-38. [DOI: 10.1007/s12275-016-5574-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 12/03/2015] [Indexed: 10/22/2022]
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Insight into the Sulfur Metabolism by Thermoacidophilic Archaeon Metallosphaera cuprina with Genomic, Proteomic and Biochemical Tools. ACTA ACUST UNITED AC 2015. [DOI: 10.4028/www.scientific.net/amr.1130.145] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract. The thermoacidophilic archaeon Metallosphaeracuprina was isolated from a sulfuric hot spring. M. cuprina is able to oxidize elemental sulfur, tetrathionate (S4O62+) pyrite, and a range of low-grade ores, thus is attractive to biomining industry. Dissimilatory sulfur metabolism with a sulfur oxygenase reductase (SOR) system has been reported for members of Sulfolobus and Acidianus. But SOR system was not identified in the genome of M. cuprina. Recently, we have explored the sulfur metabolism of M. cuprina with genomic, proteomic, and biochemical tools. A hypothetical model of sulfur metabolism in M. cuprina was proposed on proteomic and genomic data, and proteins that involved in sulfur metabolism have been identified in our following studies. Specifically, DsrE/TusA homologs were biochemically characterized, and a novel thiosulfate transfer reaction was found during sulfur oxidation with M. cuprina. More recently, we cloned and identified a CoA-dependent NAD(P)H sulfur oxidoreductase from M.cuprina. The study will cover new understandings of the sulfur metabolism with M. cuprina.
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Sant'Anna FH, Lebedinsky AV, Sokolova TG, Robb FT, Gonzalez JM. Analysis of three genomes within the thermophilic bacterial species Caldanaerobacter subterraneus with a focus on carbon monoxide dehydrogenase evolution and hydrolase diversity. BMC Genomics 2015; 16:757. [PMID: 26446804 PMCID: PMC4596419 DOI: 10.1186/s12864-015-1955-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 09/19/2015] [Indexed: 11/22/2022] Open
Abstract
Background The Caldanaerobacter subterraneus species includes thermophilic fermentative bacteria able to grow on carbohydrates substrates with acetate and L-alanine as the main products. In this study, comprehensive analysis of three genomes of C. subterraneus subspecies was carried in order to identify genes encoding key metabolic enzymes and to document the genomic basis for the evolution of these organisms. Methods Average nucleotide identity and in silico DNA relatedness were estimated for the studied C. subterraneus genomes. Genome synteny was evaluated using R2CAT software. Protein conservation was analyzed using mGenome Subtractor. Horizontal gene transfer was predicted through the GOHTAM pipeline (using tetranucleotide composition) and phylogenetic analyses (by maximum likelihood). Hydrolases were identified through the MEROPS and CAZy platforms. Results The three genomes of C. subterraneus showed high similarity, although there are substantial differences in their gene composition and organization. Each subspecies possesses a gene cluster encoding a carbon monoxide dehydrogenase (CODH) and an energy converting hydrogenase (ECH). The CODH gene is associated with an operon that resembles the Escherichia coli hydrogenase hyc/hyf operons, a novel genetic context distinct from that found in archetypical hydrogenogenic carboxydotrophs. Apart from the CODH-associated hydrogenase, these bacteria also contain other hydrogenases, encoded by ech and hyd genes. An Mbx ferredoxin:NADP oxidoreductase homolog similar to that originally described in the archaeon Pyrococcus furiosus was uniquely encoded in the C. subterraneus subsp. yonseiensis genome. Compositional analysis demonstrated that some genes of the CODH-ECH and mbx operons present distinct sequence patterns in relation to the majority of the other genes of each genome. Phylogenetic reconstructions of the genes from these operons and those from the ech operon are incongruent to the species tree. Notably, the cooS gene of C. subterraneus subsp. pacificus and its homologs in C. subterraneus subsp. tengcongensis and C. subterraneus subsp. yonseiensis form distinct clades. The strains have diverse hydrolytic enzymes and they appear to be proteolytic and glycolytic. Divergent glycosidases from 14 families, among them amylases, chitinases, alpha-glucosidases, beta-glucosidases, and cellulases, were identified. Each of the three genomes also contains around 100 proteases from 50 subfamilies, as well about ten different esterases. Conclusions Genomic information suggests that multiple horizontal gene transfers conferred the adaptation of C. subterraneus subspecies to extreme niches throughout the carbon monoxide utilization and hydrogen production. The variety of hydrolases found in their genomes indicate the versatility of the species in obtaining energy and carbon from diverse substrates, therefore these organisms constitute a remarkable resource of enzymes with biotechnological potential. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1955-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- F H Sant'Anna
- Institute of Natural Resources and Agrobiology, Spanish Council for Research, IRNAS-CSIC, Avda. Reina Mercedes 10, 41012, Sevilla, Spain. .,CAPES Foundation, Ministry of Education of Brazil, Brasília, DF, 70040-020, Brazil.
| | - A V Lebedinsky
- Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, 117312, Moscow, Russia.
| | - T G Sokolova
- Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, 117312, Moscow, Russia.
| | - F T Robb
- Department of Microbiology and Immunology, University of Maryland and Institute of Marine and Environmental Technology, 701 E Pratt Street, Baltimore, MD, 21202, USA.
| | - J M Gonzalez
- Institute of Natural Resources and Agrobiology, Spanish Council for Research, IRNAS-CSIC, Avda. Reina Mercedes 10, 41012, Sevilla, Spain.
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Sulfur vesicles from Thermococcales: A possible role in sulfur detoxifying mechanisms. Biochimie 2015; 118:356-64. [PMID: 26234734 PMCID: PMC4640147 DOI: 10.1016/j.biochi.2015.07.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/28/2015] [Indexed: 11/21/2022]
Abstract
The euryarchaeon Thermococcus prieurii inhabits deep-sea hydrothermal vents, one of the most extreme environments on Earth, which is reduced and enriched with heavy metals. Transmission electron microscopy and cryo-electron microscopy imaging of T. prieurii revealed the production of a plethora of diverse membrane vesicles (MVs) (from 50 nm to 400 nm), as is the case for other Thermococcales. T. prieurii also produces particularly long nanopods/nanotubes, some of them containing more than 35 vesicles encased in a S-layer coat. Notably, cryo-electron microscopy of T. prieurii cells revealed the presence of numerous intracellular dark vesicles that bud from the host cells via interaction with the cytoplasmic membrane. These dark vesicles are exclusively found in conjunction with T. prieurii cells and never observed in the purified membrane vesicles preparations. Energy-Dispersive-X-Ray analyses revealed that these dark vesicles are filled with sulfur. Furthermore, the presence of these sulfur vesicles (SVs) is exclusively observed when elemental sulfur was added into the growth medium. In this report, we suggest that these atypical vesicles sequester the excess sulfur not used for growth, thus preventing the accumulation of toxic levels of sulfur in the host's cytoplasm. These SVs transport elemental sulfur out of the cell where they are rapidly degraded. Intriguingly, closely related archaeal species, Thermococcus nautili and Thermococcus kodakaraensis, show some differences about the production of sulfur vesicles. Whereas T. kodakaraensis produces less sulfur vesicles than T. prieurii, T. nautili does not produce such sulfur vesicles, suggesting that Thermococcales species exhibit significant differences in their sulfur metabolic pathways.
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Proteomic Insights into Sulfur Metabolism in the Hydrogen-Producing Hyperthermophilic Archaeon Thermococcus onnurineus NA1. Int J Mol Sci 2015; 16:9167-95. [PMID: 25915030 PMCID: PMC4463584 DOI: 10.3390/ijms16059167] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 04/14/2015] [Indexed: 11/17/2022] Open
Abstract
The hyperthermophilic archaeon Thermococcus onnurineus NA1 has been shown to produce H₂ when using CO, formate, or starch as a growth substrate. This strain can also utilize elemental sulfur as a terminal electron acceptor for heterotrophic growth. To gain insight into sulfur metabolism, the proteome of T. onnurineus NA1 cells grown under sulfur culture conditions was quantified and compared with those grown under H₂-evolving substrate culture conditions. Using label-free nano-UPLC-MSE-based comparative proteomic analysis, approximately 38.4% of the total identified proteome (589 proteins) was found to be significantly up-regulated (≥1.5-fold) under sulfur culture conditions. Many of these proteins were functionally associated with carbon fixation, Fe-S cluster biogenesis, ATP synthesis, sulfur reduction, protein glycosylation, protein translocation, and formate oxidation. Based on the abundances of the identified proteins in this and other genomic studies, the pathways associated with reductive sulfur metabolism, H₂-metabolism, and oxidative stress defense were proposed. The results also revealed markedly lower expression levels of enzymes involved in the sulfur assimilation pathway, as well as cysteine desulfurase, under sulfur culture condition. The present results provide the first global atlas of proteome changes triggered by sulfur, and may facilitate an understanding of how hyperthermophilic archaea adapt to sulfur-rich, extreme environments.
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Olson DG, Sparling R, Lynd LR. Ethanol production by engineered thermophiles. Curr Opin Biotechnol 2015; 33:130-41. [PMID: 25745810 DOI: 10.1016/j.copbio.2015.02.006] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 02/11/2015] [Accepted: 02/13/2015] [Indexed: 12/17/2022]
Abstract
We compare a number of different strategies that have been pursued to engineer thermophilic microorganisms for increased ethanol production. Ethanol production from pyruvate can proceed via one of four pathways, which are named by the key pyruvate dissimilating enzyme: pyruvate decarboxylase (PDC), pyruvate dehydrogenase (PDH), pyruvate formate lyase (PFL), and pyruvate ferredoxin oxidoreductase (PFOR). For each of these pathways except PFL, we see examples where ethanol production has been engineered with a yield of >90% of the theoretical maximum. In each of these cases, this engineering was achieved mainly by modulating expression of native genes. We have not found an example where a thermophilic ethanol production pathway has been transferred to a non-ethanol-producing organism to produce ethanol at high yield. A key reason for the lack of transferability of ethanol production pathways is the current lack of understanding of the enzymes involved.
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Affiliation(s)
- Daniel G Olson
- Thayer School of Engineering at Dartmouth College, Hanover, NH 03755, United States; BioEnergy Science Center, Oak Ridge, TN 37830, United States
| | - Richard Sparling
- Department of Microbiology, University of Manitoba, Winnipeg, MB, Canada R3T 5V6
| | - Lee R Lynd
- Thayer School of Engineering at Dartmouth College, Hanover, NH 03755, United States; BioEnergy Science Center, Oak Ridge, TN 37830, United States.
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Resolution of carbon metabolism and sulfur-oxidation pathways of Metallosphaera cuprina Ar-4 via comparative proteomics. J Proteomics 2014; 109:276-89. [DOI: 10.1016/j.jprot.2014.07.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 07/03/2014] [Accepted: 07/06/2014] [Indexed: 12/16/2022]
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Primary transcriptome map of the hyperthermophilic archaeon Thermococcus kodakarensis. BMC Genomics 2014; 15:684. [PMID: 25127548 PMCID: PMC4247193 DOI: 10.1186/1471-2164-15-684] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 07/30/2014] [Indexed: 01/02/2023] Open
Abstract
Background Prokaryotes have relatively small genomes, densely-packed with protein-encoding sequences. RNA sequencing has, however, revealed surprisingly complex transcriptomes and here we report the transcripts present in the model hyperthermophilic Archaeon, Thermococcus kodakarensis, under different physiological conditions. Results Sequencing cDNA libraries, generated from RNA isolated from cells under different growth and metabolic conditions has identified >2,700 sites of transcription initiation, established a genome-wide map of transcripts, and consensus sequences for transcription initiation and post-transcription regulatory elements. The primary transcription start sites (TSS) upstream of 1,254 annotated genes, plus 644 primary TSS and their promoters within genes, are identified. Most mRNAs have a 5'-untranslated region (5'-UTR) 10 to 50 nt long (median = 16 nt), but ~20% have 5'-UTRs from 50 to 300 nt long and ~14% are leaderless. Approximately 50% of mRNAs contain a consensus ribosome binding sequence. The results identify TSS for 1,018 antisense transcripts, most with sequences complementary to either the 5'- or 3'-region of a sense mRNA, and confirm the presence of transcripts from all three CRISPR loci, the RNase P and 7S RNAs, all tRNAs and rRNAs and 69 predicted snoRNAs. Two putative riboswitch RNAs were present in growing but not in stationary phase cells. The procedure used is designed to identify TSS but, assuming that the number of cDNA reads correlates with transcript abundance, the results also provide a semi-quantitative documentation of the differences in T. kodakarensis genome expression under different growth conditions and confirm previous observations of substrate-dependent specific gene expression. Many previously unanticipated small RNAs have been identified, some with relative low GC contents (≤50%) and sequences that do not fold readily into base-paired secondary structures, contrary to the classical expectations for non-coding RNAs in a hyperthermophile. Conclusion The results identify >2,700 TSS, including almost all of the primary sites of transcription initiation upstream of annotated genes, plus many secondary sites, sites within genes and sites resulting in antisense transcripts. The T. kodakarensis genome is small (~2.1 Mbp) and tightly packed with protein-encoding genes, but the transcriptomes established also contain many non-coding RNAs and predict extensive RNA-based regulation in this model Archaeon. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-684) contains supplementary material, which is available to authorized users.
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