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St John E, Reysenbach AL. Genomic comparison of deep-sea hydrothermal genera related to Aeropyrum, Thermodiscus and Caldisphaera, and proposed emended description of the family Acidilobaceae. Syst Appl Microbiol 2024; 47:126507. [PMID: 38703419 DOI: 10.1016/j.syapm.2024.126507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/02/2024] [Accepted: 04/17/2024] [Indexed: 05/06/2024]
Abstract
Deep-sea hydrothermal vents host archaeal and bacterial thermophilic communities, including taxonomically and functionally diverse Thermoproteota. Despite their prevalence in high-temperature submarine communities, Thermoproteota are chronically under-represented in genomic databases and issues have emerged regarding their nomenclature, particularly within the Aeropyrum-Thermodiscus-Caldisphaera. To resolve some of these problems, we identified 47 metagenome-assembled genomes (MAGs) within this clade, from 20 previously published deep-sea hydrothermal vent and submarine volcano metagenomes, and 24 MAGs from public databases. Using phylogenomic analysis, Genome Taxonomy Database Toolkit (GTDB-Tk) taxonomic assessment, 16S rRNA gene phylogeny, average amino acid identity (AAI) and functional gene patterns, we re-evaluated of the taxonomy of the Aeropyrum-Thermodiscus-Caldisphaera. At least nine genus-level clades were identified with two or more MAGs. In accordance with SeqCode requirements and recommendations, we propose names for three novel genera, viz. Tiamatella incendiivivens, Hestiella acidicharens and Calypsonella navitae. A fourth genus was also identified related to Thermodiscus maritimus, for which no available sequenced genome exists. We propose the novel species Thermodiscus eudorianus to describe our high-quality Thermodiscus MAG, which represents the type genome for the genus. All three novel genera and T. eudorianus are likely anaerobic heterotrophs, capable of fermenting protein-rich carbon sources, while some Tiamatella, Calypsonella and T. eudorianus may also reduce polysulfides, thiosulfate, sulfur and/or selenite, and the likely acidophile, Hestiella, may reduce nitrate and/or perchlorate. Based on phylogenomic evidence, we also propose the family Acidilobaceae be amended to include Caldisphaera, Aeropyrum, Thermodiscus and Stetteria and the novel genera described here.
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Affiliation(s)
- Emily St John
- Center for Life in Extreme Environments, Portland State University, Portland, OR 97201, USA.
| | - Anna-Louise Reysenbach
- Center for Life in Extreme Environments, Portland State University, Portland, OR 97201, USA.
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Song B, Guo H, Chen Z, Xu Q, Chen L, Bai X. Analysis of landfill leachate promoting efficient application of weathered coal anaerobic fermentation. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 273:116151. [PMID: 38412633 DOI: 10.1016/j.ecoenv.2024.116151] [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: 11/12/2023] [Revised: 02/21/2024] [Accepted: 02/22/2024] [Indexed: 02/29/2024]
Abstract
This research aimed to develop a new method for clean utilization and treatment of landfill leachate and solid waste weathered coal. Landfill leachate and weathered coal were adopted for combined anaerobic fermentation for methane production. The characteristics of microbial community, mechanism of biological methane production, and utilization characteristics of fermentation broth and solid residue for co-fermentation were analyzed through metagenomics, soluble organic matter detection and thermogravimetric (TG) analysis. The obtained results revealed that combined anaerobic fermentation increased methane production by 80.1%. Syntrophomonas, Salipiger, Methanosaeta and Methanothrix were highly correlated. Gene abundances of 2-oxoacid ferredoxin oxidoreductase and enolase were increased in methane conversion pathway mainly by acetic acid. Pyruvate-ferroredoxin oxidoreductase, 2-oxoglutarate synthase and succinate dehydrogenase acetate synthase intensified electron transfer pathways among microorganisms. Fulvic acid, tyrosine and tryptophan contents were high in fermentation broth. Volatile decomposition temperature, ignition point and residual char combustion temperature of residual coal were decreased and combustion was more stable. The obtained results showed that the co-fermentation of landfill leachate and weathered coal improved biological methane gas production, degraded weathered coal and improved combustion performance, which provided a new idea for weathered coal clean utilization.
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Affiliation(s)
- Bo Song
- School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China
| | - Hongyu Guo
- School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China; Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization, Henan Polytechnic University, Jiaozuo 454000, China.
| | - Zhenhong Chen
- Research Institute of Petroleum Exploration & Development, Beijing 100083, China
| | - Qiang Xu
- General Prospecting Institute of China National Administration of Coal Geology, Beijing 100039,China
| | - Linyong Chen
- College of Computer Science and Technology, Henan Polytechnic University, Jiaozuo 454000, China
| | - Xiujia Bai
- General Prospecting Institute of China National Administration of Coal Geology, Beijing 100039,China
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Sulfite altered permanganate pretreatment effects on the volatile fatty acid production during sludge anaerobic fermentation. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2022.122514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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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: 1.7] [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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Dai X, Wang H, Zhang Z, Li K, Zhang X, Mora-López M, Jiang C, Liu C, Wang L, Zhu Y, Hernández-Ascencio W, Dong Z, Huang L. Genome Sequencing of Sulfolobus sp. A20 from Costa Rica and Comparative Analyses of the Putative Pathways of Carbon, Nitrogen, and Sulfur Metabolism in Various Sulfolobus Strains. Front Microbiol 2016; 7:1902. [PMID: 27965637 PMCID: PMC5127849 DOI: 10.3389/fmicb.2016.01902] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 11/14/2016] [Indexed: 11/13/2022] Open
Abstract
The genome of Sulfolobus sp. A20 isolated from a hot spring in Costa Rica was sequenced. This circular genome of the strain is 2,688,317 bp in size and 34.8% in G+C content, and contains 2591 open reading frames (ORFs). Strain A20 shares ~95.6% identity at the 16S rRNA gene sequence level and <30% DNA-DNA hybridization (DDH) values with the most closely related known Sulfolobus species (i.e., Sulfolobus islandicus and Sulfolobus solfataricus), suggesting that it represents a novel Sulfolobus species. Comparison of the genome of strain A20 with those of the type strains of S. solfataricus, Sulfolobus acidocaldarius, S. islandicus, and Sulfolobus tokodaii, which were isolated from geographically separated areas, identified 1801 genes conserved among all Sulfolobus species analyzed (core genes). Comparative genome analyses show that central carbon metabolism in Sulfolobus is highly conserved, and enzymes involved in the Entner-Doudoroff pathway, the tricarboxylic acid cycle and the CO2 fixation pathways are predominantly encoded by the core genes. All Sulfolobus species encode genes required for the conversion of ammonium into glutamate/glutamine. Some Sulfolobus strains have gained the ability to utilize additional nitrogen source such as nitrate (i.e., S. islandicus strain REY15A, LAL14/1, M14.25, and M16.27) or urea (i.e., S. islandicus HEV10/4, S. tokodaii strain7, and S. metallicus DSM 6482). The strategies for sulfur metabolism are most diverse and least understood. S. tokodaii encodes sulfur oxygenase/reductase (SOR), whereas both S. islandicus and S. solfataricus contain genes for sulfur reductase (SRE). However, neither SOR nor SRE genes exist in the genome of strain A20, raising the possibility that an unknown pathway for the utilization of elemental sulfur may be present in the strain. The ability of Sulfolobus to utilize nitrate or sulfur is encoded by a gene cluster flanked by IS elements or their remnants. These clusters appear to have become fixed at a specific genomic site in some strains and lost in other strains during the course of evolution. The versatility in nitrogen and sulfur metabolism may represent adaptation of Sulfolobus to thriving in different habitats.
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Affiliation(s)
- Xin Dai
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
| | - Haina Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
| | - Zhenfeng Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Kuan Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Xiaoling Zhang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Marielos Mora-López
- Center for Research in Cell and Molecular Biology, Universidad de Costa Rica San José, Costa Rica
| | - Chengying Jiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Chang Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
| | - Li Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Yaxin Zhu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | | | - Zhiyang Dong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Li Huang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
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Yan Z, Maruyama A, Arakawa T, Fushinobu S, Wakagi T. Crystal structures of archaeal 2-oxoacid:ferredoxin oxidoreductases from Sulfolobus tokodaii. Sci Rep 2016; 6:33061. [PMID: 27619895 PMCID: PMC5020499 DOI: 10.1038/srep33061] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/16/2016] [Indexed: 11/22/2022] Open
Abstract
As the first three-dimensional structure of the two-subunit type 2-oxoacid:ferredoxin oxidoreductases (OFOR) from archaea, we solved the crystal structures of STK_23000/STK_22980 (StOFOR1) and STK_24350/STK_24330 (StOFOR2) from Sulfolobus tokodaii. They showed similar overall structures, consisting of two a- and b-subunit heterodimers containing thiamin pyrophosphate (TPP) cofactor and [4Fe-4S] cluster, but lack an intramolecular ferredoxin domain. Unlike other OFORs, StOFORs can utilize both pyruvate and 2-oxoglutarate, playing a key role in the central metabolism. In the structure of StOFOR2 in unreacted pyruvate complex form, carboxylate group of pyruvate is recognized by Arg344 and Thr257 from the a-subunit, which are conserved in pyruvate:ferredoxin oxidoreductase from Desulfovbrio africanus (DaPFOR). In the structure of StOFOR1 co-crystallized with 2-oxobutyrate, electron density corresponding to a 1-hydroxypropyl group (post-decarboxylation state) was observed at the thiazole ring of TPP. The binding pockets of the StOFORs surrounding the methyl or propyl group of the ligands are wider than that of DaPFOR. Mutational analyses indicated that several residues were responsible for the broad 2-oxoacid specificity of StOFORs. We also constructed a possible complex structural model by placing a Zn(2+)-containing dicluster ferredoxin of S. tokodaii into the large pocket of StOFOR2, providing insight into the electron transfer between the two redox proteins.
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Affiliation(s)
- Zhen Yan
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Akane Maruyama
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Takatoshi Arakawa
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shinya Fushinobu
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Takayoshi Wakagi
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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8
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Pierce E, Becker DF, Ragsdale SW. Identification and characterization of oxalate oxidoreductase, a novel thiamine pyrophosphate-dependent 2-oxoacid oxidoreductase that enables anaerobic growth on oxalate. J Biol Chem 2010; 285:40515-24. [PMID: 20956531 PMCID: PMC3003350 DOI: 10.1074/jbc.m110.155739] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 10/15/2010] [Indexed: 11/06/2022] Open
Abstract
Moorella thermoacetica is an anaerobic acetogen, a class of bacteria that is found in the soil, the animal gastrointestinal tract, and the rumen. This organism engages the Wood-Ljungdahl pathway of anaerobic CO(2) fixation for heterotrophic or autotrophic growth. This paper describes a novel enzyme, oxalate oxidoreductase (OOR), that enables M. thermoacetica to grow on oxalate, which is produced in soil and is a common component of kidney stones. Exposure to oxalate leads to the induction of three proteins that are subunits of OOR, which oxidizes oxalate coupled to the production of two electrons and CO(2) or bicarbonate. Like other members of the 2-oxoacid:ferredoxin oxidoreductase family, OOR contains thiamine pyrophosphate and three [Fe(4)S(4)] clusters. However, unlike previously characterized members of this family, OOR does not use coenzyme A as a substrate. Oxalate is oxidized with a k(cat) of 0.09 s(-1) and a K(m) of 58 μM at pH 8. OOR also oxidizes a few other 2-oxoacids (which do not induce OOR) also without any requirement for CoA. The enzyme transfers its reducing equivalents to a broad range of electron acceptors, including ferredoxin and the nickel-dependent carbon monoxide dehydrogenase. In conjunction with the well characterized Wood-Ljungdahl pathway, OOR should be sufficient for oxalate metabolism by M. thermoacetica, and it constitutes a novel pathway for oxalate metabolism.
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Affiliation(s)
- Elizabeth Pierce
- From the Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606 and
| | - Donald F. Becker
- the Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - Stephen W. Ragsdale
- From the Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606 and
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The role of PerR in O2-affected gene expression of Clostridium acetobutylicum. J Bacteriol 2009; 191:6082-93. [PMID: 19648241 DOI: 10.1128/jb.00351-09] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
In the strict anaerobe Clostridium acetobutylicum, a PerR-homologous protein has recently been identified as being a key repressor of a reductive machinery for the scavenging of reactive oxygen species and molecular O(2). In the absence of PerR, the full derepression of its regulon resulted in increased resistance to oxidative stress and nearly full tolerance of an aerobic environment. In the present study, the complementation of a Bacillus subtilis PerR mutant confirmed that the homologous protein from C. acetobutylicum acts as a functional peroxide sensor in vivo. Furthermore, we used a transcriptomic approach to analyze gene expression in the aerotolerant PerR mutant strain and compared it to the O(2) stimulon of wild-type C. acetobutylicum. The genes encoding the components of the alternative detoxification system were PerR regulated. Only few other targets of direct PerR regulation were identified, including two highly expressed genes encoding enzymes that are putatively involved in the central energy metabolism. All of them were highly induced when wild-type cells were exposed to sublethal levels of O(2). Under these conditions, C. acetobutylicum also activated the repair and biogenesis of DNA and Fe-S clusters as well as the transcription of a gene encoding an unknown CO dehydrogenase-like enzyme. Surprisingly few genes were downregulated when exposed to O(2), including those involved in butyrate formation. In summary, these results show that the defense of this strict anaerobe against oxidative stress is robust and by far not limited to the removal of O(2) and its reactive derivatives.
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Podar M, Anderson I, Makarova KS, Elkins JG, Ivanova N, Wall MA, Lykidis A, Mavromatis K, Sun H, Hudson ME, Chen W, Deciu C, Hutchison D, Eads JR, Anderson A, Fernandes F, Szeto E, Lapidus A, Kyrpides NC, Saier MH, Richardson PM, Rachel R, Huber H, Eisen JA, Koonin EV, Keller M, Stetter KO. A genomic analysis of the archaeal system Ignicoccus hospitalis-Nanoarchaeum equitans. Genome Biol 2008; 9:R158. [PMID: 19000309 PMCID: PMC2614490 DOI: 10.1186/gb-2008-9-11-r158] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 10/21/2008] [Accepted: 11/10/2008] [Indexed: 01/03/2023] Open
Abstract
Sequencing of the complete genome of Ignicoccus hospitalis gives insight into its association with another species of Archaea, Nanoarchaeum equitans. Background The relationship between the hyperthermophiles Ignicoccus hospitalis and Nanoarchaeum equitans is the only known example of a specific association between two species of Archaea. Little is known about the mechanisms that enable this relationship. Results We sequenced the complete genome of I. hospitalis and found it to be the smallest among independent, free-living organisms. A comparative genomic reconstruction suggests that the I. hospitalis lineage has lost most of the genes associated with a heterotrophic metabolism that is characteristic of most of the Crenarchaeota. A streamlined genome is also suggested by a low frequency of paralogs and fragmentation of many operons. However, this process appears to be partially balanced by lateral gene transfer from archaeal and bacterial sources. Conclusions A combination of genomic and cellular features suggests highly efficient adaptation to the low energy yield of sulfur-hydrogen respiration and efficient inorganic carbon and nitrogen assimilation. Evidence of lateral gene exchange between N. equitans and I. hospitalis indicates that the relationship has impacted both genomes. This association is the simplest symbiotic system known to date and a unique model for studying mechanisms of interspecific relationships at the genomic and metabolic levels.
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Affiliation(s)
- Mircea Podar
- Biosciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37831, USA.
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