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Sadeghi M, Mestivier D, Carbonnelle E, Benamouzig R, Khazaie K, Sobhani I. Loss of symbiotic and increase of virulent bacteria through microbial networks in Lynch syndrome colon carcinogenesis. Front Oncol 2024; 13:1313735. [PMID: 38375206 PMCID: PMC10876293 DOI: 10.3389/fonc.2023.1313735] [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: 10/10/2023] [Accepted: 12/14/2023] [Indexed: 02/21/2024] Open
Abstract
Purpose Through a pilot study, we performed whole gut metagenomic analysis in 17 Lynch syndrome (LS) families, including colorectal cancer (CRC) patients and their healthy first-degree relatives. In a second asymptomatic LS cohort (n=150) undergoing colonoscopy-screening program, individuals with early precancerous lesions were compared to those with a normal colonoscopy. Since bacteria are organized into different networks within the microbiota, we compared related network structures in patients and controls. Experimental design Fecal prokaryote DNA was extracted prior to colonoscopy for whole metagenome (n=34, pilot study) or 16s rRNA sequencing (validation study). We characterized bacteria taxonomy using Diamond/MEGAN6 and DADA2 pipelines and performed differential abundances using Shaman website. We constructed networks using SparCC inference tools and validated the construction's accuracy by performing qPCR on selected bacteria. Results Significant differences in bacterial communities in LS-CRC patients were identified, with an enrichment of virulent bacteria and a depletion of symbionts compared to their first-degree relatives. Bacteria taxa in LS asymptomatic individuals with colonic precancerous lesions (n=79) were significantly different compared to healthy individuals (n=71). The main bacterial network structures, constructed based on bacteria-bacteria correlations in CRC (pilot study) and in asymptomatic precancerous patients (validation-study), showed a different pattern than in controls. It was characterized by virulent/symbiotic co-exclusion in both studies and illustrated (validation study) by a higher Escherichia/Bifidobacterium ratio, as assessed by qPCR. Conclusion Enhanced fecal virulent/symbiotic bacteria ratios influence bacterial network structures. As an early event in colon carcinogenesis, these ratios can be used to identify asymptomatic LS individual with a higher risk of CRC.
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Affiliation(s)
- Mohammad Sadeghi
- EA7375 –EC2M3: Early detection of Colonic Cancer by using Microbial & Molecular Markers Paris East Créteil University (UPEC), Créteil, France
| | - Denis Mestivier
- EA7375 –EC2M3: Early detection of Colonic Cancer by using Microbial & Molecular Markers Paris East Créteil University (UPEC), Créteil, France
| | - Etienne Carbonnelle
- Bacteriology, Virology, Hygiene Laboratory, Assistance Publique–Hôpitaux de Paris (APHP), Avicenne Hospital, Bobigny, France
| | - Robert Benamouzig
- Department of Gastroenterology, Assistance Publique–Hôpitaux de Paris (APHP), Avicenne Hospital, Bobigny, France
| | | | - Iradj Sobhani
- EA7375 –EC2M3: Early detection of Colonic Cancer by using Microbial & Molecular Markers Paris East Créteil University (UPEC), Créteil, France
- Department of Gastroenterology, Assistance Publique–Hôpitaux de Paris (APHP), Henri Mondor Hospital, Créteil, France
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Wu B, Liu F, Fang W, Yang T, Chen GH, He Z, Wang S. Microbial sulfur metabolism and environmental implications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146085. [PMID: 33714092 DOI: 10.1016/j.scitotenv.2021.146085] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/19/2021] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
Sulfur as a macroelement plays an important role in biochemistry in both natural environments and engineering biosystems, which can be further linked to other important element cycles, e.g. carbon, nitrogen and iron. Consequently, the sulfur cycling primarily mediated by sulfur compounds oxidizing microorganisms and sulfur compounds reducing microorganisms has enormous environmental implications, particularly in wastewater treatment and pollution bioremediation. In this review, to connect the knowledge in microbial sulfur metabolism to environmental applications, we first comprehensively review recent advances in understanding microbial sulfur metabolisms at molecular-, cellular- and ecosystem-levels, together with their energetics. We then discuss the environmental implications to fight against soil and water pollution, with four foci: (1) acid mine drainage, (2) water blackening and odorization in urban rivers, (3) SANI® and DS-EBPR processes for sewage treatment, and (4) bioremediation of persistent organic pollutants. In addition, major challenges and further developments toward elucidation of microbial sulfur metabolisms and their environmental applications are identified and discussed.
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Affiliation(s)
- Bo Wu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510006, China
| | - Feifei Liu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China
| | - Wenwen Fang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510006, China
| | - Tony Yang
- Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, Swift Current, SK S9H 3X2, Canada
| | - Guang-Hao Chen
- Department of Civil & Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Zhili He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510006, China
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510006, China.
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3
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Qian Z, Tianwei H, Mackey HR, van Loosdrecht MCM, Guanghao C. Recent advances in dissimilatory sulfate reduction: From metabolic study to application. WATER RESEARCH 2019; 150:162-181. [PMID: 30508713 DOI: 10.1016/j.watres.2018.11.018] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/25/2018] [Accepted: 11/08/2018] [Indexed: 05/24/2023]
Abstract
Sulfate-reducing bacteria (SRB) are a group of diverse anaerobic microorganisms omnipresent in natural habitats and engineered environments that use sulfur compounds as the electron acceptor for energy metabolism. Dissimilatory sulfate reduction (DSR)-based techniques mediated by SRB have been utilized in many sulfate-containing wastewater treatment systems worldwide, particularly for acid mine drainage, groundwater, sewage and industrial wastewater remediation. However, DSR processes are often operated suboptimally and disturbances are common in practical application. To improve the efficiency and robustness of SRB-based processes, it is necessary to study SRB metabolism and operational conditions. In this review, the mechanisms of DSR processes are reviewed and discussed focusing on intracellular and extracellular electron transfer with different electron donors (hydrogen, organics, methane and electrodes). Based on the understanding of the metabolism of SRB, responses of SRB to environmental stress (pH-, temperature-, and salinity-related stress) are summarized at the species and community levels. Application in these stressed conditions is discussed and future research is proposed. The feasibility of recovering energy and resources such as biohydrogen, hydrocarbons, polyhydroxyalkanoates, magnetite and metal sulfides through the use of SRB were investigated but some long-standing questions remain unanswered. Linking the existing scientific understanding and observations to practical application is the challenge as always for promotion of SRB-based techniques.
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Affiliation(s)
- Zeng Qian
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Hao Tianwei
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China; Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
| | - Hamish Robert Mackey
- Division of Sustainable Development, College of Science and Engineering, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | | | - Chen Guanghao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China; Water Technology Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Hong Kong, China; Wastewater Treatment Laboratory, FYT Graduate School, The Hong Kong University of Science and Technology, Nansha, Guangzhou, China.
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4
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Pavan ME, Pavan EE, Glaeser SP, Etchebehere C, Kämpfer P, Pettinari MJ, López NI. Proposal for a new classification of a deep branching bacterial phylogenetic lineage: transfer of Coprothermobacter proteolyticus and Coprothermobacter platensis to Coprothermobacteraceae fam. nov., within Coprothermobacterales ord. nov., Coprothermobacteria classis nov. and Coprothermobacterota phyl. nov. and emended description of the family Thermodesulfobiaceae. Int J Syst Evol Microbiol 2018; 68:1627-1632. [PMID: 29595416 DOI: 10.1099/ijsem.0.002720] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The genus Coprothermobacter (initially named Thermobacteroides) is currently placed within the phylum Firmicutes. Early 16S rRNA gene based phylogenetic studies pointed out the great differences between Coprothermobacter and other members of the Firmicutes, revealing that it constitutes a new deep branching lineage. Over the years, several studies based on 16S rRNA gene and whole genome sequences have indicated that Coprothermobacter is very distant phylogenetically to all other bacteria, supporting its placement in a distinct deeply rooted novel phylum. In view of this, we propose its allocation to the new family Coprothermobacteraceae within the novel order Coprothermobacterales, the new class Coprothermobacteria, and the new phylum Coprothermobacterota, and an emended description of the family Thermodesulfobiaceae.
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Affiliation(s)
- María Elisa Pavan
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Esteban E Pavan
- Biomedical Technologies Laboratory, Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - Stefanie P Glaeser
- Institut für Angewandte Mikrobiologie, Universität Giessen, Giessen, Germany
| | - Claudia Etchebehere
- Microbial Ecology Laboratory, Department of Biochemistry and Microbial Genetics, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
| | - Peter Kämpfer
- Institut für Angewandte Mikrobiologie, Universität Giessen, Giessen, Germany
| | - María Julia Pettinari
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,IQUIBICEN-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Nancy I López
- IQUIBICEN-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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5
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Frank YA, Kadnikov VV, Lukina AP, Banks D, Beletsky AV, Mardanov AV, Sen'kina EI, Avakyan MR, Karnachuk OV, Ravin NV. Characterization and Genome Analysis of the First Facultatively Alkaliphilic Thermodesulfovibrio Isolated from the Deep Terrestrial Subsurface. Front Microbiol 2016; 7:2000. [PMID: 28066337 PMCID: PMC5165239 DOI: 10.3389/fmicb.2016.02000] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 11/29/2016] [Indexed: 11/16/2022] Open
Abstract
Members of the genus Thermodesulfovibrio belong to the Nitrospirae phylum and all isolates characterized to date are neutrophiles. They have been isolated from terrestrial hot springs and thermophilic methanogenic anaerobic sludges. Their molecular signatures have, however, also been detected in deep subsurface. The purpose of this study was to characterize and analyze the genome of a newly isolated, facultatively alkaliphilic Thermodesulfovibrio from a 2 km deep aquifer system in Western Siberia, Russia. The new isolate, designated N1, grows optimally at pH 8.5 and at 65°C. It is able to reduce sulfate, thiosulfate or sulfite with a limited range of electron donors, such as formate, pyruvate, and lactate. Analysis of the 1.93 Mb draft genome of strain N1 revealed that it contains a set of genes for dissimilatory sulfate reduction, including sulfate adenyltransferase, adenosine-5′-phosphosulfate reductase AprAB, membrane-bound electron transfer complex QmoABC, dissimilatory sulfite reductase DsrABC, and sulfite reductase-associated electron transfer complex DsrMKJOP. Hydrogen turnover is enabled by soluble cytoplasmic, membrane-linked, and soluble periplasmic hydrogenases. The use of thiosulfate as an electron acceptor is enabled by a membrane-linked molybdopterin oxidoreductase. The N1 requirement for organic carbon sources corresponds to the lack of the autotrophic C1-fixation pathways. Comparative analysis of the genomes of Thermodesulfovibrio (T. yellowstonii, T. islandicus, T. àggregans, T. thiophilus, and strain N1) revealed a low overall genetic diversity and several adaptive traits. Consistent with an alkaliphilic lifestyle, a multisubunit Na+/H+ antiporter of the Mnh family is encoded in the Thermodesulfovibrio strain N1 genome. Nitrogenase genes were found in T. yellowstonii, T. aggregans, and T. islandicus, nitrate reductase in T. islandicus, and cellulose synthetase in T. aggregans and strain N1. Overall, our results provide genomic insights into metabolism of the Thermodesulfovibrio lineage in microbial communities of the deep subsurface biosphere.
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Affiliation(s)
- Yulia A Frank
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University Tomsk, Russia
| | - Vitaly V Kadnikov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences Moscow, Russia
| | - Anastasia P Lukina
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University Tomsk, Russia
| | - David Banks
- Systems, Power and Energy, School of Engineering, Glasgow UniversityGlasgow, UK; Holymoor Consultancy Ltd.Chesterfield, UK
| | - Alexey V Beletsky
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences Moscow, Russia
| | - Andrey V Mardanov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences Moscow, Russia
| | - Elena I Sen'kina
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University Tomsk, Russia
| | - Marat R Avakyan
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University Tomsk, Russia
| | - Olga V Karnachuk
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University Tomsk, Russia
| | - Nikolai V Ravin
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences Moscow, Russia
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6
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Gagliano M, Braguglia C, Petruccioli M, Rossetti S. Ecology and biotechnological potential of the thermophilic fermentative Coprothermobacter spp. FEMS Microbiol Ecol 2015; 91:fiv018. [DOI: 10.1093/femsec/fiv018] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2015] [Indexed: 12/29/2022] Open
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7
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Lau MCY, Cameron C, Magnabosco C, Brown CT, Schilkey F, Grim S, Hendrickson S, Pullin M, Sherwood Lollar B, van Heerden E, Kieft TL, Onstott TC. Phylogeny and phylogeography of functional genes shared among seven terrestrial subsurface metagenomes reveal N-cycling and microbial evolutionary relationships. Front Microbiol 2014; 5:531. [PMID: 25400621 PMCID: PMC4215791 DOI: 10.3389/fmicb.2014.00531] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/24/2014] [Indexed: 11/30/2022] Open
Abstract
Comparative studies on community phylogenetics and phylogeography of microorganisms living in extreme environments are rare. Terrestrial subsurface habitats are valuable for studying microbial biogeographical patterns due to their isolation and the restricted dispersal mechanisms. Since the taxonomic identity of a microorganism does not always correspond well with its functional role in a particular community, the use of taxonomic assignments or patterns may give limited inference on how microbial functions are affected by historical, geographical and environmental factors. With seven metagenomic libraries generated from fracture water samples collected from five South African mines, this study was carried out to (1) screen for ubiquitous functions or pathways of biogeochemical cycling of CH4, S, and N; (2) to characterize the biodiversity represented by the common functional genes; (3) to investigate the subsurface biogeography as revealed by this subset of genes; and (4) to explore the possibility of using metagenomic data for evolutionary study. The ubiquitous functional genes are NarV, NPD, PAPS reductase, NifH, NifD, NifK, NifE, and NifN genes. Although these eight common functional genes were taxonomically and phylogenetically diverse and distinct from each other, the dissimilarity between samples did not correlate strongly with geographical or environmental parameters or residence time of the water. Por genes homologous to those of Thermodesulfovibrio yellowstonii detected in all metagenomes were deep lineages of Nitrospirae, suggesting that subsurface habitats have preserved ancestral genetic signatures that inform the study of the origin and evolution of prokaryotes.
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Affiliation(s)
- Maggie C Y Lau
- Department of Geosciences, Princeton University Princeton, NJ, USA
| | | | - Cara Magnabosco
- Department of Geosciences, Princeton University Princeton, NJ, USA
| | - C Titus Brown
- Department of Computer Science and Engineering and Department of Microbiology and Molecular Genetics, Michigan State University East Lansing, MI, USA
| | - Faye Schilkey
- National Center for Genome Resources Santa Fe, NM, USA
| | - Sharon Grim
- The Marine Biological Laboratory Woods Hole, MA, USA
| | | | - Michael Pullin
- Department of Chemistry, New Mexico Tech Socorro, NM, USA
| | | | - Esta van Heerden
- Department of Biotechnology, University of Free State Bloemfontein, South Africa
| | | | - Tullis C Onstott
- Department of Geosciences, Princeton University Princeton, NJ, USA
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8
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Genomic insights into the uncultured genus 'Candidatus Magnetobacterium' in the phylum Nitrospirae. ISME JOURNAL 2014; 8:2463-77. [PMID: 24914800 DOI: 10.1038/ismej.2014.94] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 04/27/2014] [Accepted: 05/08/2014] [Indexed: 11/09/2022]
Abstract
Magnetotactic bacteria (MTB) of the genus 'Candidatus Magnetobacterium' in phylum Nitrospirae are of great interest because of the formation of hundreds of bullet-shaped magnetite magnetosomes in multiple bundles of chains per cell. These bacteria are worldwide distributed in aquatic environments and have important roles in the biogeochemical cycles of iron and sulfur. However, except for a few short genomic fragments, no genome data are available for this ecologically important genus, and little is known about their metabolic capacity owing to the lack of pure cultures. Here we report the first draft genome sequence of 3.42 Mb from an uncultivated strain tentatively named 'Ca. Magnetobacterium casensis' isolated from Lake Miyun, China. The genome sequence indicates an autotrophic lifestyle using the Wood-Ljungdahl pathway for CO2 fixation, which has not been described in any previously known MTB or Nitrospirae organisms. Pathways involved in the denitrification, sulfur oxidation and sulfate reduction have been predicted, indicating its considerable capacity for adaptation to variable geochemical conditions and roles in local biogeochemical cycles. Moreover, we have identified a complete magnetosome gene island containing mam, mad and a set of novel genes (named as man genes) putatively responsible for the formation of bullet-shaped magnetite magnetosomes and the arrangement of multiple magnetosome chains. This first comprehensive genomic analysis sheds light on the physiology, ecology and biomineralization of the poorly understood 'Ca. Magnetobacterium' genus.
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Lücker S, Nowka B, Rattei T, Spieck E, Daims H. The Genome of Nitrospina gracilis Illuminates the Metabolism and Evolution of the Major Marine Nitrite Oxidizer. Front Microbiol 2013; 4:27. [PMID: 23439773 PMCID: PMC3578206 DOI: 10.3389/fmicb.2013.00027] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 02/02/2013] [Indexed: 01/17/2023] Open
Abstract
In marine systems, nitrate is the major reservoir of inorganic fixed nitrogen. The only known biological nitrate-forming reaction is nitrite oxidation, but despite its importance, our knowledge of the organisms catalyzing this key process in the marine N-cycle is very limited. The most frequently encountered marine NOB are related to Nitrospina gracilis, an aerobic chemolithoautotrophic bacterium isolated from ocean surface waters. To date, limited physiological and genomic data for this organism were available and its phylogenetic affiliation was uncertain. In this study, the draft genome sequence of N. gracilis strain 3/211 was obtained. Unexpectedly for an aerobic organism, N. gracilis lacks classical reactive oxygen defense mechanisms and uses the reductive tricarboxylic acid cycle for carbon fixation. These features indicate microaerophilic ancestry and are consistent with the presence of Nitrospina in marine oxygen minimum zones. Fixed carbon is stored intracellularly as glycogen, but genes for utilizing external organic carbon sources were not identified. N. gracilis also contains a full gene set for oxidative phosphorylation with oxygen as terminal electron acceptor and for reverse electron transport from nitrite to NADH. A novel variation of complex I may catalyze the required reverse electron flow to low-potential ferredoxin. Interestingly, comparative genomics indicated a strong evolutionary link between Nitrospina, the nitrite-oxidizing genus Nitrospira, and anaerobic ammonium oxidizers, apparently including the horizontal transfer of a periplasmically oriented nitrite oxidoreductase and other key genes for nitrite oxidation at an early evolutionary stage. Further, detailed phylogenetic analyses using concatenated marker genes provided evidence that Nitrospina forms a novel bacterial phylum, for which we propose the name Nitrospinae.
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Affiliation(s)
- Sebastian Lücker
- Department of Microbial Ecology, Ecology Centre, University of Vienna Vienna, Austria
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10
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Francke C, Groot Kormelink T, Hagemeijer Y, Overmars L, Sluijter V, Moezelaar R, Siezen RJ. Comparative analyses imply that the enigmatic Sigma factor 54 is a central controller of the bacterial exterior. BMC Genomics 2011; 12:385. [PMID: 21806785 PMCID: PMC3162934 DOI: 10.1186/1471-2164-12-385] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 08/01/2011] [Indexed: 02/06/2023] Open
Abstract
Background Sigma-54 is a central regulator in many pathogenic bacteria and has been linked to a multitude of cellular processes like nitrogen assimilation and important functional traits such as motility, virulence, and biofilm formation. Until now it has remained obscure whether these phenomena and the control by Sigma-54 share an underlying theme. Results We have uncovered the commonality by performing a range of comparative genome analyses. A) The presence of Sigma-54 and its associated activators was determined for all sequenced prokaryotes. We observed a phylum-dependent distribution that is suggestive of an evolutionary relationship between Sigma-54 and lipopolysaccharide and flagellar biosynthesis. B) All Sigma-54 activators were identified and annotated. The relation with phosphotransfer-mediated signaling (TCS and PTS) and the transport and assimilation of carboxylates and nitrogen containing metabolites was substantiated. C) The function annotations, that were represented within the genomic context of all genes encoding Sigma-54, its activators and its promoters, were analyzed for intra-phylum representation and inter-phylum conservation. Promoters were localized using a straightforward scoring strategy that was formulated to identify similar motifs. We found clear highly-represented and conserved genetic associations with genes that concern the transport and biosynthesis of the metabolic intermediates of exopolysaccharides, flagella, lipids, lipopolysaccharides, lipoproteins and peptidoglycan. Conclusion Our analyses directly implicate Sigma-54 as a central player in the control over the processes that involve the physical interaction of an organism with its environment like in the colonization of a host (virulence) or the formation of biofilm.
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Affiliation(s)
- Christof Francke
- TI Food and Nutrition, P,O,Box 557, 6700AN Wageningen, The Netherlands.
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11
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Abstract
BACKGROUND Genome sequencing has revolutionized our view of the relationships among genomes, particularly in revealing the confounding effects of lateral genetic transfer (LGT). Phylogenomic techniques have been used to construct purported trees of microbial life. Although such trees are easily interpreted and allow the use of a subset of genomes as "proxies" for the full set, LGT and other phenomena impact the positioning of different groups in genome trees, confounding and potentially invalidating attempts to construct a phylogeny-based taxonomy of microorganisms. Network and graph approaches can reveal complex sets of relationships, but applying these techniques to large data sets is a significant challenge. Notwithstanding the question of what exactly it might represent, generating and interpreting a Tree or Network of All Genomes will only be feasible if current algorithms can be improved upon. RESULTS Complex relationships among even the most-similar genomes demonstrate that proxy-based approaches to simplifying large sets of genomes are not alone sufficient to solve the analysis problem. A phylogenomic analysis of 1173 sequenced bacterial and archaeal genomes generated phylogenetic trees for 159,905 distinct homologous gene sets. The relationships inferred from this set can be heavily dependent on the inclusion of other taxa: for example, phyla such as Spirochaetes, Proteobacteria and Firmicutes are recovered as cohesive groups or split depending on the presence of other specific lineages. Furthermore, named groups such as Acidithiobacillus, Coprothermobacter and Brachyspira show a multitude of affiliations that are more consistent with their ecology than with small subunit ribosomal DNA-based taxonomy. Network and graph representations can illustrate the multitude of conflicting affinities, but all methods impose constraints on the input data and create challenges of construction and interpretation. CONCLUSIONS These complex relationships highlight the need for an inclusive approach to genomic data, and current methods with minor alterations will likely scale to allow the analysis of data sets with 10,000 or more genomes. The main challenges lie in the visualization and interpretation of genomic relationships, and the redefinition of microbial taxonomy when subsets of genomic data are so evidently in conflict with one another, and with the "canonical" molecular taxonomy.
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Affiliation(s)
- Robert G Beiko
- Faculty of Computer Science, Dalhousie University, Halifax, NS B3H 1W5 Canada.
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Kunisawa T. The phylogenetic placement of the non-phototrophic, Gram-positive thermophile 'Thermobaculum terrenum' and branching orders within the phylum 'Chloroflexi' inferred from gene order comparisons. Int J Syst Evol Microbiol 2010; 61:1944-1953. [PMID: 20833875 DOI: 10.1099/ijs.0.026088-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The phylogenetic position of an anaerobic, non-spore-forming thermophile 'Thermobaculum terrenum' was investigated on the basis of gene order data from completely sequenced bacterial genomes. Gene order data can be an excellent source of phylogenetic information. Shared gene arrangements are unlikely to have arisen by chance convergence. They are likely to reflect common ancestry. 'Thermobaculum terrenum' was found to share three gene arrangements that are present uniquely in genomes of members of the phylum 'Chloroflexi', indicating convincingly that 'Thermobaculum terrenum' is a member of this phylum. Branching orders within the phylum 'Chloroflexi' were inferred by identifying monophyletic groups of species, which were circumscribed by characteristic gene arrangements. The branching orders thus inferred were in good agreement with previously reported phylogenies based on single 16S rRNA gene sequences and on multiple protein sequences. The gene order comparisons revealed a close phylogenetic affinity of 'Thermobaculum terrenum' to Sphaerobacter thermophilus and Thermomicrobium roseum.
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Affiliation(s)
- Takashi Kunisawa
- Department of Applied Biological Sciences, Science University of Tokyo, 2641 Yamasaki, Noda 278-8510, Japan
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Kunisawa T. Inference of the phylogenetic position of the phylum Deferribacteres from gene order comparison. Antonie van Leeuwenhoek 2010; 99:417-22. [PMID: 20706870 DOI: 10.1007/s10482-010-9492-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 07/30/2010] [Indexed: 12/22/2022]
Abstract
The phylogenetic placement of the phylum Deferribacteres was investigated on the basis of gene order comparisons of completely sequenced bacterial genomes. Two completely sequenced Deferribacteres species share five sets of gene arrangements with a group of phyla, Proteobacteria, Aquificae, Planctomycetes, Spirochaetes, Bacteroidetes, Chlorobi, Acidobacteria, Verrucomicrobia, Elusimicrobia and Nitrospirae, while the other group of phyla, Synergistetes, Firmicutes, Actinobacteria, Thermotogae, Chloroflexi and Deinococcus-Thermus, Fusobacteria, shares alternative sets of gene arrangements, suggesting that the Deferribacteres is classified in the former group of phyla. Gene transfers that are thought to have occurred in a common ancestor of the Deferribacteres, Deltaproteobacteria and Nitrospirae exclusive of virtually all other phyla were identified, which suggests that the Deferribacteres is phylogenetically proximal to the Proteobacteria and Nitrospirae.
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Affiliation(s)
- Takashi Kunisawa
- Department of Applied Biological Sciences, Science University of Tokyo, Noda, Japan.
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