1
|
Rodríguez-Cruz UE, Castelán-Sánchez HG, Madrigal-Trejo D, Eguiarte LE, Souza V. Uncovering novel bacterial and archaeal diversity: genomic insights from metagenome-assembled genomes in Cuatro Cienegas, Coahuila. Front Microbiol 2024; 15:1369263. [PMID: 38873164 PMCID: PMC11169877 DOI: 10.3389/fmicb.2024.1369263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 05/03/2024] [Indexed: 06/15/2024] Open
Abstract
A comprehensive study was conducted in the Cuatro Ciénegas Basin (CCB) in Coahuila, Mexico, which is known for its diversity of microorganisms and unique physicochemical properties. The study focused on the "Archaean Domes" (AD) site in the CCB, which is characterized by an abundance of hypersaline, non-lithifying microbial mats. In AD, we analyzed the small domes and circular structures using metagenome assembly genomes (MAGs) with the aim of expanding our understanding of the prokaryotic tree of life by uncovering previously unreported lineages, as well as analyzing the diversity of bacteria and archaea in the CCB. A total of 325 MAGs were identified, including 48 Archaea and 277 Bacteria. Remarkably, 22 archaea and 104 bacteria could not be classified even at the genus level, highlighting the remarkable novel diversity of the CCB. Besides, AD site exhibited significant diversity at the phylum level, with Proteobacteria being the most abundant, followed by Desulfobacteria, Spirochaetes, Bacteroidetes, Nanoarchaeota, Halobacteriota, Cyanobacteria, Planctomycetota, Verrucomicrobiota, Actinomycetes and Chloroflexi. In Archaea, the monophyletic groups of MAGs belonged to the Archaeoglobi, Aenigmarchaeota, Candidate Nanoarchaeota, and Halobacteriota. Among Bacteria, monophyletic groups were also identified, including Spirochaetes, Proteobacteria, Planctomycetes, Actinobacteria, Verrucomicrobia, Bacteroidetes, Candidate Bipolaricaulota, Desulfobacteria, and Cyanobacteria. These monophyletic groups were possibly influenced by geographic isolation, as well as the extreme and fluctuating environmental conditions in the pond AD, such as stoichiometric imbalance of C:N:P of 122:42:1, fluctuating pH (5-9.8) and high salinity (5.28% to saturation).
Collapse
Affiliation(s)
- Ulises E. Rodríguez-Cruz
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
- Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | | | - David Madrigal-Trejo
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Luis E. Eguiarte
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Valeria Souza
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
- Centro de Estudios del Cuaternario de Fuego, Patagonia y Antártica (CEQUA), Punta Arenas, Chile
| |
Collapse
|
2
|
Machulin AV, Deryusheva EI, Galzitskaya OV. Variation in base composition, structure-function relationships, and origins of structural repetition in bacterial rpsA gene. Biosystems 2024; 238:105196. [PMID: 38537772 DOI: 10.1016/j.biosystems.2024.105196] [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: 10/03/2023] [Revised: 03/22/2024] [Accepted: 03/22/2024] [Indexed: 04/12/2024]
Abstract
Protein domain repeats are known to arise due to tandem duplications of internal genes. However, the understanding of the underlying mechanisms of this process is incomplete. The goal of this work was to investigate the mechanism of occurrence of repeat expansion based on studying the sequences of 1324 rpsA genes of bacterial S1 ribosomal proteins containing different numbers of S1 structural domains. The rpsA gene encodes ribosomal S1 protein, which is essential for cell viability as it interacts with both mRNA and proteins. Gene ontology (GO) analysis of S1 domains in ribosomal S1 proteins revealed that bacterial protein sequences in S1 mainly have 3 types of molecular functions: RNA binding activity, nucleic acid activity, and ribosome structural component. Our results show that the maximum value of rpsA gene identity for full-length proteins was found for S1 proteins containing six structural domains (58%). Analysis of consensus sequences showed that parts of the rpsA gene encoding separate S1 domains have no a strictly repetitive structure between groups containing different numbers of S1 domains. At the same time, gene regions encoding some conserved residues that form the RNA-binding site remain conserved. The detected phylogenetic similarity suggests that the proposed fold of the rpsA translation initiation region of Escherichia coli has functional value and is important for translational control of rpsA gene expression in other bacterial phyla, but not only in gamma Proteobacteria.
Collapse
Affiliation(s)
- Andrey V Machulin
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290, Pushchino, Moscow Region, Russia
| | - Evgeniya I Deryusheva
- Institute for Biological Instrumentation, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290, Pushchino, Moscow Region, Russia
| | - Oxana V Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences, 142290, Pushchino, Moscow Region, Russia; Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290, Pushchino, Moscow Region, Russia.
| |
Collapse
|
3
|
González D, Morales-Olavarria M, Vidal-Veuthey B, Cárdenas JP. Insights into early evolutionary adaptations of the Akkermansia genus to the vertebrate gut. Front Microbiol 2023; 14:1238580. [PMID: 37779688 PMCID: PMC10540074 DOI: 10.3389/fmicb.2023.1238580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 08/21/2023] [Indexed: 10/03/2023] Open
Abstract
Akkermansia, a relevant mucin degrader from the vertebrate gut microbiota, is a member of the deeply branched Verrucomicrobiota, as well as the only known member of this phylum to be described as inhabitants of the gut. Only a few Akkermansia species have been officially described so far, although there is genomic evidence addressing the existence of more species-level variants for this genus. This niche specialization makes Akkermansia an interesting model for studying the evolution of microorganisms to their adaptation to the gastrointestinal tract environment, including which kind of functions were gained when the Akkermansia genus originated or how the evolutionary pressure functions over those genes. In order to gain more insight into Akkermansia adaptations to the gastrointestinal tract niche, we performed a phylogenomic analysis of 367 high-quality Akkermansia isolates and metagenome-assembled genomes, in addition to other members of Verrucomicrobiota. This work was focused on three aspects: the definition of Akkermansia genomic species clusters and the calculation and functional characterization of the pangenome for the most represented species; the evolutionary relationship between Akkermansia and their closest relatives from Verrucomicrobiota, defining the gene families which were gained or lost during the emergence of the last Akkermansia common ancestor (LAkkCA) and; the evaluation of the evolutionary pressure metrics for each relevant gene family of main Akkermansia species. This analysis found 25 Akkermansia genomic species clusters distributed in two main clades, divergent from their non-Akkermansia relatives. Pangenome analyses suggest that Akkermansia species have open pangenomes, and the gene gain/loss model indicates that genes associated with mucin degradation (both glycoside hydrolases and peptidases), (micro)aerobic metabolism, surface interaction, and adhesion were part of LAkkCA. Specifically, mucin degradation is a very ancestral innovation involved in the origin of Akkermansia. Horizontal gene transfer detection suggests that Akkermansia could receive genes mostly from unknown sources or from other Gram-negative gut bacteria. Evolutionary metrics suggest that Akkemansia species evolved differently, and even some conserved genes suffered different evolutionary pressures among clades. These results suggest a complex evolutionary landscape of the genus and indicate that mucin degradation could be an essential feature in Akkermansia evolution as a symbiotic species.
Collapse
Affiliation(s)
- Dámariz González
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
| | - Mauricio Morales-Olavarria
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
| | - Boris Vidal-Veuthey
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
| | - Juan P. Cárdenas
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
- Escuela de Biotecnología, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
| |
Collapse
|
4
|
Ghotaslou R, Nabizadeh E, Memar MY, Law WMH, Ozma MA, Abdi M, Yekani M, Kadkhoda H, hosseinpour R, Bafadam S, Ghotaslou A, Leylabadlo HE, Nezhadi J. The metabolic, protective, and immune functions of Akkermansia muciniphila. Microbiol Res 2023; 266:127245. [DOI: 10.1016/j.micres.2022.127245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 10/25/2022] [Accepted: 10/25/2022] [Indexed: 11/07/2022]
|
5
|
Dharamshi JE, Köstlbacher S, Schön ME, Collingro A, Ettema TJG, Horn M. Gene gain facilitated endosymbiotic evolution of Chlamydiae. Nat Microbiol 2023; 8:40-54. [PMID: 36604515 PMCID: PMC9816063 DOI: 10.1038/s41564-022-01284-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 11/07/2022] [Indexed: 01/07/2023]
Abstract
Chlamydiae is a bacterial phylum composed of obligate animal and protist endosymbionts. However, other members of the Planctomycetes-Verrucomicrobia-Chlamydiae superphylum are primarily free living. How Chlamydiae transitioned to an endosymbiotic lifestyle is still largely unresolved. Here we reconstructed Planctomycetes-Verrucomicrobia-Chlamydiae species relationships and modelled superphylum genome evolution. Gene content reconstruction from 11,996 gene families suggests a motile and facultatively anaerobic last common Chlamydiae ancestor that had already gained characteristic endosymbiont genes. Counter to expectations for genome streamlining in strict endosymbionts, we detected substantial gene gain within Chlamydiae. We found that divergence in energy metabolism and aerobiosis observed in extant lineages emerged later during chlamydial evolution. In particular, metabolic and aerobic genes characteristic of the more metabolically versatile protist-infecting chlamydiae were gained, such as respiratory chain complexes. Our results show that metabolic complexity can increase during endosymbiont evolution, adding an additional perspective for understanding symbiont evolutionary trajectories across the tree of life.
Collapse
Affiliation(s)
- Jennah E Dharamshi
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Stephan Köstlbacher
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Vienna, Austria
- University of Vienna, Doctoral School in Microbiology and Environmental Science, Vienna, Austria
- Laboratory of Microbiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Max E Schön
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Astrid Collingro
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Vienna, Austria
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden.
- Laboratory of Microbiology, Wageningen University and Research, Wageningen, The Netherlands.
| | - Matthias Horn
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Vienna, Austria.
| |
Collapse
|
6
|
The C-Terminal Repeat Units of SpaA Mediate Adhesion of Erysipelothrix rhusiopathiae to Host Cells and Regulate Its Virulence. BIOLOGY 2022; 11:biology11071010. [PMID: 36101391 PMCID: PMC9311908 DOI: 10.3390/biology11071010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/22/2022] [Accepted: 06/27/2022] [Indexed: 11/17/2022]
Abstract
Simple Summary Erysipelothrix rhusiopathiae is an important zoonotic pathogen, which poses a serious harm to the pig industry. We aimed to evaluate the genomic differences between virulent and avirulent strains to study the pathogenic mechanism of Erysipelothrix rhusiopathiae. The results showed that the spaA gene of avirulent strain lacked 120bp, encoding repeat units at the C-terminal of SpaA, the virulence of the virulent strain with this 120 bp deletion was attenuated, and the mutant strain decreased adhesion to porcine iliac artery endothelial cells. Abstract Erysipelothrix rhusiopathiae is a causative agent of erysipelas in animals and erysipeloid in humans. However, current information regarding E. rhusiopathiae pathogenesis remains limited. Previously, we identified two E. rhusiopathiae strains, SE38 and G4T10, which were virulent and avirulent in pigs, respectively. Here, to further study the pathogenic mechanism of E. rhusiopathiae, we sequenced and assembled the genomes of strains SE38 and G4T10, and performed a comparative genomic analysis to identify differences or mutations in virulence-associated genes. Next, we comparatively analyzed 25 E. rhusiopathiae virulence-associated genes in SE38 and G4T10. Compared with that of SE38, the spaA gene of the G4T10 strain lacked 120 bp, encoding repeat units at the C-terminal of SpaA. To examine whether these deletions or splits influence E. rhusiopathiae virulence, these 120 bp were successfully deleted from the spaA gene in strain SE38 by homologous recombination. The mutant strain ΔspaA displayed attenuated virulence in mice and decreased adhesion to porcine iliac artery endothelial cells, which was also observed using the corresponding mutant protein SpaA’. Our results demonstrate that SpaA-mediated adhesion between E. rhusiopathiae and host cells is dependent on its C-terminal repeat units.
Collapse
|
7
|
Deryusheva E, Machulin A, Matyunin M, Galzitskaya O. Sequence and evolutionary analysis of bacterial ribosomal S1 proteins. Proteins 2021; 89:1111-1124. [PMID: 33843105 DOI: 10.1002/prot.26084] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 03/17/2021] [Accepted: 04/07/2021] [Indexed: 12/21/2022]
Abstract
The multi-domain bacterial S1 protein is the largest and most functionally important ribosomal protein of the 30S subunit, which interacts with both mRNA and proteins. The family of ribosomal S1 proteins differs in the classical sense from a protein with tandem repeats and has a "bead-on-string" organization, where each repeat is folded into a globular domain. Based on our recent data, the study of evolutionary relationships for the bacterial phyla will provide evidence for one of the proposed theories of the evolutionary development of proteins with structural repeats: from multiple repeats of assembles to single repeats, or vice versa. In this comparative analysis of 1333 S1 sequences that were identified in 24 different phyla, we demonstrate how such phyla can form independently/dependently during evolution. To the best of our knowledge, this work is the first study of the evolutionary history of bacterial ribosomal S1 proteins. The collected and structured data can be useful to computer biologists as a resource for determining percent identity, amino acid composition and logo motifs, as well as dN/dS ratio in bacterial S1 protein. The obtained research data indicate that the evolutionary development of bacterial ribosomal S1 proteins evolved from multiple assemblies to single repeat. The presented data are integrated into the server, which can be accessed at http://oka.protres.ru:4200.
Collapse
Affiliation(s)
- Evgeniya Deryusheva
- Institute for Biological Instrumentation, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Russian Federation
| | - Andrey Machulin
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Russian Federation
| | - Maxim Matyunin
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russian Federation
| | - Oxana Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russian Federation.,Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russian Federation
| |
Collapse
|
8
|
Colpaert M, Kadouche D, Ducatez M, Pillonel T, Kebbi-Beghdadi C, Cenci U, Huang B, Chabi M, Maes E, Coddeville B, Couderc L, Touzet H, Bray F, Tirtiaux C, Ball S, Greub G, Colleoni C. Conservation of the glycogen metabolism pathway underlines a pivotal function of storage polysaccharides in Chlamydiae. Commun Biol 2021; 4:296. [PMID: 33674787 PMCID: PMC7935935 DOI: 10.1038/s42003-021-01794-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/03/2021] [Indexed: 01/31/2023] Open
Abstract
The order Chlamydiales includes obligate intracellular pathogens capable of infecting mammals, fishes and amoeba. Unlike other intracellular bacteria for which intracellular adaptation led to the loss of glycogen metabolism pathway, all chlamydial families maintained the nucleotide-sugar dependent glycogen metabolism pathway i.e. the GlgC-pathway with the notable exception of both Criblamydiaceae and Waddliaceae families. Through detailed genome analysis and biochemical investigations, we have shown that genome rearrangement events have resulted in a defective GlgC-pathway and more importantly we have evidenced a distinct trehalose-dependent GlgE-pathway in both Criblamydiaceae and Waddliaceae families. Altogether, this study strongly indicates that the glycogen metabolism is retained in all Chlamydiales without exception, highlighting the pivotal function of storage polysaccharides, which has been underestimated to date. We propose that glycogen degradation is a mandatory process for fueling essential metabolic pathways that ensure the survival and virulence of extracellular forms i.e. elementary bodies of Chlamydiales.
Collapse
Affiliation(s)
- Matthieu Colpaert
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Derifa Kadouche
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Mathieu Ducatez
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Trestan Pillonel
- Institute of Microbiology, University of Lausanne and University Hospital Center, Lausanne, Switzerland
| | - Carole Kebbi-Beghdadi
- Institute of Microbiology, University of Lausanne and University Hospital Center, Lausanne, Switzerland
| | - Ugo Cenci
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Binquan Huang
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan/School of Agriculture, Yunnan University, Kunming, China
| | - Malika Chabi
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Emmanuel Maes
- University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41 - UMS 2014 - PLBS, Lille, France
| | - Bernadette Coddeville
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Loïc Couderc
- University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41 - UMS 2014 - PLBS, Lille, France
| | - Hélène Touzet
- University of Lille, CNRS, Centrale Lille, UMR 9189 - CRIStAL - Centre de Recherche en Informatique Signal et Automatique de Lille, Lille, France
| | - Fabrice Bray
- University of Lille, CNRS, USR 3290-MSAP-Miniaturisation pour la Synthèse, l'Analyse et la Protéomique, Lille, France
| | - Catherine Tirtiaux
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Steven Ball
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Gilbert Greub
- Institute of Microbiology, University of Lausanne and University Hospital Center, Lausanne, Switzerland
| | - Christophe Colleoni
- University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France.
| |
Collapse
|
9
|
Köstlbacher S, Collingro A, Halter T, Domman D, Horn M. Coevolving Plasmids Drive Gene Flow and Genome Plasticity in Host-Associated Intracellular Bacteria. Curr Biol 2021; 31:346-357.e3. [PMID: 33157023 PMCID: PMC7846284 DOI: 10.1016/j.cub.2020.10.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/30/2020] [Accepted: 10/09/2020] [Indexed: 12/30/2022]
Abstract
Plasmids are important in microbial evolution and adaptation to new environments. Yet, carrying a plasmid can be costly, and long-term association of plasmids with their hosts is poorly understood. Here, we provide evidence that the Chlamydiae, a phylum of strictly host-associated intracellular bacteria, have coevolved with their plasmids since their last common ancestor. Current chlamydial plasmids are amalgamations of at least one ancestral plasmid and a bacteriophage. We show that the majority of plasmid genes are also found on chromosomes of extant chlamydiae. The most conserved plasmid gene families are predominantly vertically inherited, while accessory plasmid gene families show significantly increased mobility. We reconstructed the evolutionary history of plasmid gene content of an entire bacterial phylum over a period of around one billion years. Frequent horizontal gene transfer and chromosomal integration events illustrate the pronounced impact of coevolution with these extrachromosomal elements on bacterial genome dynamics in host-dependent microbes.
Collapse
Affiliation(s)
- Stephan Köstlbacher
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology, Althanstrasse 14, Vienna 1090, Austria
| | - Astrid Collingro
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology, Althanstrasse 14, Vienna 1090, Austria
| | - Tamara Halter
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology, Althanstrasse 14, Vienna 1090, Austria
| | - Daryl Domman
- Wellcome Sanger Institute, Parasites and Microbes Programme, Hinxton, Cambridge CB10 1SA, UK; Center for Global Health, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Matthias Horn
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology, Althanstrasse 14, Vienna 1090, Austria.
| |
Collapse
|
10
|
Microbial Evolution: Chlamydial Creatures from the Deep. Curr Biol 2020; 30:R267-R269. [PMID: 32208150 DOI: 10.1016/j.cub.2020.01.086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A metagenomic study of marine sediments from a hydrothermal vent field in the Arctic Mid-Ocean Ridge revealed wider diversity amongst members of the phylum Chlamydiae than was previously known. Unlike known chlamydiae, some of the newly described marine-sediment species may be potentially free-living.
Collapse
|
11
|
Collingro A, Köstlbacher S, Horn M. Chlamydiae in the Environment. Trends Microbiol 2020; 28:877-888. [PMID: 32591108 DOI: 10.1016/j.tim.2020.05.020] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/25/2020] [Accepted: 05/28/2020] [Indexed: 12/19/2022]
Abstract
Chlamydiae have been known for more than a century as major pathogens of humans. Yet they are also found ubiquitously in the environment where they thrive within protists and in an unmatched wide range of animals. This review summarizes recent advances in understanding chlamydial diversity and distribution in nature. Studying these environmental chlamydiae provides a novel perspective on basic chlamydial biology and evolution. A picture is beginning to emerge with chlamydiae representing one of the evolutionarily most ancient and successful groups of obligate intracellular bacteria.
Collapse
Affiliation(s)
- Astrid Collingro
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Stephan Köstlbacher
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Matthias Horn
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.
| |
Collapse
|
12
|
Dharamshi JE, Tamarit D, Eme L, Stairs CW, Martijn J, Homa F, Jørgensen SL, Spang A, Ettema TJG. Marine Sediments Illuminate Chlamydiae Diversity and Evolution. Curr Biol 2020; 30:1032-1048.e7. [PMID: 32142706 DOI: 10.1016/j.cub.2020.02.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 12/22/2019] [Accepted: 02/06/2020] [Indexed: 12/20/2022]
Abstract
The bacterial phylum Chlamydiae is so far composed of obligate symbionts of eukaryotic hosts. Well known for Chlamydiaceae, pathogens of humans and other animals, Chlamydiae also include so-called environmental lineages that primarily infect microbial eukaryotes. Environmental surveys indicate that Chlamydiae are found in a wider range of environments than anticipated previously. However, the vast majority of this chlamydial diversity has been underexplored, biasing our current understanding of their biology, ecological importance, and evolution. Here, we report that previously undetected and active chlamydial lineages dominate microbial communities in deep anoxic marine sediments taken from the Arctic Mid-Ocean Ridge. Reaching relative abundances of up to 43% of the bacterial community, and a maximum diversity of 163 different species-level taxonomic units, these Chlamydiae represent important community members. Using genome-resolved metagenomics, we reconstructed 24 draft chlamydial genomes, expanding by over a third the known genomic diversity in this phylum. Phylogenomic analyses revealed several novel clades across the phylum, including a previously unknown sister lineage of the Chlamydiaceae, providing new insights into the origin of pathogenicity in this family. We were unable to identify putative eukaryotic hosts for these marine sediment chlamydiae, despite identifying genomic features that may be indicative of host-association. The high abundance and genomic diversity of Chlamydiae in these anoxic marine sediments indicate that some members could play an important, and thus far overlooked, ecological role in such environments and may indicate alternate lifestyle strategies.
Collapse
Affiliation(s)
- Jennah E Dharamshi
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden
| | - Daniel Tamarit
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden; Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Wageningen 6708 WE, the Netherlands
| | - Laura Eme
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden; Unité d'Ecologie, Systématique et Evolution, CNRS, Université Paris-Sud, Orsay 91400, France
| | - Courtney W Stairs
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden
| | - Joran Martijn
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden; Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Felix Homa
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden; Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Wageningen 6708 WE, the Netherlands
| | - Steffen L Jørgensen
- Department of Earth Science, Centre for Deep Sea Research, University of Bergen, Bergen 5020, Norway
| | - Anja Spang
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden; Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Burg 1790 AB, the Netherlands
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala 75123, Sweden; Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Wageningen 6708 WE, the Netherlands.
| |
Collapse
|
13
|
Mahajan M, Yee B, Hägglund E, Guy L, Fuerst JA, Andersson SGE. Paralogization and New Protein Architectures in Planctomycetes Bacteria with Complex Cell Structures. Mol Biol Evol 2019; 37:1020-1040. [DOI: 10.1093/molbev/msz287] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Abstract
Bacteria of the phylum Planctomycetes have a unique cell plan with an elaborate intracellular membrane system, thereby resembling eukaryotic cells. The origin and evolution of these remarkable features is debated. To study the evolutionary genomics of bacteria with complex cell architectures, we have resequenced the 9.2-Mb genome of the model organism Gemmata obscuriglobus and sequenced the 10-Mb genome of G. massiliana Soil9, the 7.9-Mb genome of CJuql4, and the 6.7-Mb genome of Tuwongella immobilis, all of which belong to the family Gemmataceae. A gene flux analysis of the Planctomycetes revealed a massive emergence of novel protein families at multiple nodes within the Gemmataceae. The expanded protein families have unique multidomain architectures composed of domains that are characteristic of prokaryotes, such as the sigma factor domain of extracytoplasmic sigma factors, and domains that have proliferated in eukaryotes, such as the WD40, leucine-rich repeat, tetratricopeptide repeat and Ser/Thr kinase domains. Proteins with identifiable domains in the Gemmataceae have longer lengths and linkers than proteins in most other bacteria, and the analyses suggest that these traits were ancestrally present in the Planctomycetales. A broad comparison of protein length distribution profiles revealed an overlap between the longest proteins in prokaryotes and the shortest proteins in eukaryotes. We conclude that the many similarities between proteins in the Planctomycetales and the eukaryotes are due to convergent evolution and that there is no strict boundary between prokaryotes and eukaryotes with regard to features such as gene paralogy, protein length, and protein domain composition patterns.
Collapse
Affiliation(s)
- Mayank Mahajan
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Benjamin Yee
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Emil Hägglund
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Lionel Guy
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Uppsala, Sweden
- Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - John A Fuerst
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Siv G E Andersson
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Uppsala, Sweden
| |
Collapse
|
14
|
Machulin AV, Deryusheva EI, Selivanova OM, Galzitskaya OV. The number of domains in the ribosomal protein S1 as a hallmark of the phylogenetic grouping of bacteria. PLoS One 2019; 14:e0221370. [PMID: 31437214 PMCID: PMC6705787 DOI: 10.1371/journal.pone.0221370] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/05/2019] [Indexed: 01/18/2023] Open
Abstract
The family of ribosomal proteins S1 contains about 20% of all bacterial proteins including the S1 domain. An important feature of this family is multiple copies of structural domains in bacteria, the number of which changes in a strictly limited range from one to six. In this study, the automated exhaustive analysis of 1453 sequences of S1 allowed us to demonstrate that the number of domains in S1 is a distinctive characteristic for phylogenetic bacterial grouping in main phyla. 1453 sequences of S1 were identified in 25 out of 30 different phyla according to the List of Prokaryotic Names with Standing in Nomenclature. About 62% of all records are identified as six-domain S1 proteins, which belong to phylum Proteobacteria. Four-domain S1 are identified mainly in proteins from phylum Firmicutes and Actinobacteria. Records belonging to these phyla are 33% of all records. The least represented two-domain S1 are about 0.6% of all records. The third and fourth domains for the most representative four- and six-domain S1 have the highest percentage of identity with the S1 domain from polynucleotide phosphorylase and S1 domains from one-domain S1. In addition, for these groups, the central part of S1 (the third domain) is more conserved than the terminal domains.
Collapse
Affiliation(s)
- Andrey V. Machulin
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, Pushchino, Moscow Region, Russia
| | - Evgenia I. Deryusheva
- Institute for Biological Instrumentation, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, Pushchino, Moscow Region, Russia
| | - Olga M. Selivanova
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Oxana V. Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| |
Collapse
|
15
|
Taylor-Brown A, Pillonel T, Greub G, Vaughan L, Nowak B, Polkinghorne A. Metagenomic Analysis of Fish-Associated Ca. Parilichlamydiaceae Reveals Striking Metabolic Similarities to the Terrestrial Chlamydiaceae. Genome Biol Evol 2018; 10:2587-2595. [PMID: 30202970 PMCID: PMC6171736 DOI: 10.1093/gbe/evy195] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2018] [Indexed: 12/13/2022] Open
Abstract
Chlamydiae are an example of obligate intracellular bacteria that possess highly reduced, compact genomes (1.0-3.5 Mbp), reflective of their abilities to sequester many essential nutrients from the host that they no longer need to synthesize themselves. The Chlamydiae is a phylum with a very wide host range spanning mammals, birds, fish, invertebrates, and unicellular protists. This ecological and phylogenetic diversity offers ongoing opportunities to study intracellular survival and metabolic pathways and adaptations. Of particular evolutionary significance are Chlamydiae from the recently proposed Ca. Parilichlamydiaceae, the earliest diverging clade in this phylum, species of which are found only in aquatic vertebrates. Gill extracts from three Chlamydiales-positive Australian aquaculture species (Yellowtail kingfish, Striped trumpeter, and Barramundi) were subject to DNA preparation to deplete host DNA and enrich microbial DNA, prior to metagenome sequencing. We assembled chlamydial genomes corresponding to three Ca. Parilichlamydiaceae species from gill metagenomes, and conducted functional genomics comparisons with diverse members of the phylum. This revealed highly reduced genomes more similar in size to the terrestrial Chlamydiaceae, standing in contrast to members of the Chlamydiae with a demonstrated cosmopolitan host range. We describe a reduction in genes encoding synthesis of nucleotides and amino acids, among other nutrients, and an enrichment of predicted transport proteins. Ca. Parilichlamydiaceae share 342 orthologs with other chlamydial families. We hypothesize that the genome reduction exhibited by Ca. Parilichlamydiaceae and Chlamydiaceae is an example of within-phylum convergent evolution. The factors driving these events remain to be elucidated.
Collapse
Affiliation(s)
- Alyce Taylor-Brown
- USC Animal Research Centre, Faculty of Science, Engineering and Education, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Trestan Pillonel
- Institute of Microbiology, University of Lausanne and University Hospital Center, Switzerland
| | - Gilbert Greub
- Institute of Microbiology, University of Lausanne and University Hospital Center, Switzerland
| | - Lloyd Vaughan
- Institute of Veterinary Pathology, University of Zurich, Switzerland.,Pathovet AG, Tagelswangen, Switzerland
| | - Barbara Nowak
- Institute of Marine and Antarctic Studies, University of Tasmania, Newnham, Tasmania, Australia
| | - Adam Polkinghorne
- USC Animal Research Centre, Faculty of Science, Engineering and Education, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| |
Collapse
|
16
|
Rivas-Marín E, Devos DP. The Paradigms They Are a-Changin': past, present and future of PVC bacteria research. Antonie van Leeuwenhoek 2017; 111:785-799. [PMID: 29058138 PMCID: PMC5945725 DOI: 10.1007/s10482-017-0962-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/10/2017] [Indexed: 11/22/2022]
Abstract
These are exciting times for PVC researchers! The PVC superphylum is composed of the bacterial phyla Planctomycetes, Verrucomicrobia, Chlamydiae (those three founders giving it its name), Lentisphaerae and Kirimatiellaeota as well as some uncultured candidate phyla, such as the Candidatus Omnitrophica (previously known as OP3). Despite early debates, most of the disagreements that surround this group of bacteria have been recently resolved. In this article, we review the history of the study of PVC bacteria, with a particular focus on the misinterpretations that emerged early in the field and their resolution. We begin with a historical perspective that describes the relevant facts of PVC research from the early times when they were not yet termed PVC. Those were controversial times and we refer to them as the “discovery age” of the field. We continue by describing new discoveries due to novel techniques and data that combined with the reinterpretations of old ones have contributed to solve most of the discordances and we refer to these times as the “illumination age” of PVC research. We follow by arguing that we are just entering the “golden age” of PVC research and that the future of this growing community is looking bright. We finish by suggesting a few of the directions that PVC researches might take in the future.
Collapse
Affiliation(s)
- Elena Rivas-Marín
- Centro Andaluz de Biología del Desarrollo (CABD)-CSIC, University Pablo de Olavide, Carretera Utrera, km 1, 41013, Seville, Spain
| | - Damien P Devos
- Centro Andaluz de Biología del Desarrollo (CABD)-CSIC, University Pablo de Olavide, Carretera Utrera, km 1, 41013, Seville, Spain.
| |
Collapse
|
17
|
He S, Stevens SLR, Chan LK, Bertilsson S, Glavina del Rio T, Tringe SG, Malmstrom RR, McMahon KD. Ecophysiology of Freshwater Verrucomicrobia Inferred from Metagenome-Assembled Genomes. mSphere 2017; 2:e00277-17. [PMID: 28959738 PMCID: PMC5615132 DOI: 10.1128/msphere.00277-17] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/05/2017] [Indexed: 11/20/2022] Open
Abstract
Microbes are critical in carbon and nutrient cycling in freshwater ecosystems. Members of the Verrucomicrobia are ubiquitous in such systems, and yet their roles and ecophysiology are not well understood. In this study, we recovered 19 Verrucomicrobia draft genomes by sequencing 184 time-series metagenomes from a eutrophic lake and a humic bog that differ in carbon source and nutrient availabilities. These genomes span four of the seven previously defined Verrucomicrobia subdivisions and greatly expand knowledge of the genomic diversity of freshwater Verrucomicrobia. Genome analysis revealed their potential role as (poly)saccharide degraders in freshwater, uncovered interesting genomic features for this lifestyle, and suggested their adaptation to nutrient availabilities in their environments. Verrucomicrobia populations differ significantly between the two lakes in glycoside hydrolase gene abundance and functional profiles, reflecting the autochthonous and terrestrially derived allochthonous carbon sources of the two ecosystems, respectively. Interestingly, a number of genomes recovered from the bog contained gene clusters that potentially encode a novel porin-multiheme cytochrome c complex and might be involved in extracellular electron transfer in the anoxic humus-rich environment. Notably, most epilimnion genomes have large numbers of so-called "Planctomycete-specific" cytochrome c-encoding genes, which exhibited distribution patterns nearly opposite to those seen with glycoside hydrolase genes, probably associated with the different levels of environmental oxygen availability and carbohydrate complexity between lakes/layers. Overall, the recovered genomes represent a major step toward understanding the role, ecophysiology, and distribution of Verrucomicrobia in freshwater. IMPORTANCE Freshwater Verrucomicrobia spp. are cosmopolitan in lakes and rivers, and yet their roles and ecophysiology are not well understood, as cultured freshwater Verrucomicrobia spp. are restricted to one subdivision of this phylum. Here, we greatly expanded the known genomic diversity of this freshwater lineage by recovering 19 Verrucomicrobia draft genomes from 184 metagenomes collected from a eutrophic lake and a humic bog across multiple years. Most of these genomes represent the first freshwater representatives of several Verrucomicrobia subdivisions. Genomic analysis revealed Verrucomicrobia to be potential (poly)saccharide degraders and suggested their adaptation to carbon sources of different origins in the two contrasting ecosystems. We identified putative extracellular electron transfer genes and so-called "Planctomycete-specific" cytochrome c-encoding genes and identified their distinct distribution patterns between the lakes/layers. Overall, our analysis greatly advances the understanding of the function, ecophysiology, and distribution of freshwater Verrucomicrobia, while highlighting their potential role in freshwater carbon cycling.
Collapse
Affiliation(s)
- Shaomei He
- Department of Bacteriology, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Geoscience, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Sarah L. R. Stevens
- Department of Bacteriology, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | | | - Stefan Bertilsson
- Department of Ecology and Genetics, Limnology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | | | | | | | - Katherine D. McMahon
- Department of Bacteriology, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin, USA
| |
Collapse
|
18
|
Pinos S, Pontarotti P, Raoult D, Merhej V. Identification of constraints influencing the bacterial genomes evolution in the PVC super-phylum. BMC Evol Biol 2017; 17:75. [PMID: 28274202 PMCID: PMC5343374 DOI: 10.1186/s12862-017-0921-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/21/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Horizontal transfer plays an important role in the evolution of bacterial genomes, yet it obeys several constraints, including the ecological opportunity to meet other organisms, the presence of transfer systems, and the fitness of the transferred genes. Bacteria from the Planctomyctetes, Verrumicrobia, Chlamydiae (PVC) super-phylum have a compartmentalized cell plan delimited by an intracytoplasmic membrane that might constitute an additional constraint with particular impact on bacterial evolution. In this investigation, we studied the evolution of 33 genomes from PVC species and focused on the rate and the nature of horizontally transferred sequences in relation to their habitat and their cell plan. RESULTS Using a comparative phylogenomic approach, we showed that habitat influences the evolution of the bacterial genome's content and the flux of horizontal transfer of DNA (HT). Thus bacteria from soil, from insects and ubiquitous bacteria presented the highest average of horizontal transfer compared to bacteria living in water, extracellular bacteria in vertebrates, bacteria from amoeba and intracellular bacteria in vertebrates (with a mean of 379 versus 110 events per species, respectively and 7.6% of each genomes due to HT against 4.8%). The partners of these transfers were mainly bacterial organisms (94.9%); they allowed us to differentiate environmental bacteria, which exchanged more with Proteobacteria, and bacteria from vertebrates, which exchanged more with Firmicutes. The functional analysis of the horizontal transfers revealed a convergent evolution, with an over-representation of genes encoding for membrane biogenesis and lipid metabolism, among compartmentalized bacteria in the different habitats. CONCLUSIONS The presence of an intracytoplasmic membrane in PVC species seems to affect the genome's evolution through the selection of transferred DNA, according to their encoded functions.
Collapse
Affiliation(s)
- Sandrine Pinos
- Aix Marseille Université, CNRS, Centrale Marseille, I2M UMR 7373, Evolution Biologique et Modélisation, 3 place Victor Hugo, Marseille, 13331 France
- Aix Marseille Univ, CNRS, IRD, INSERM, AP-HM URMITE, IHU -Méditerranée Infection, 19-21 Boulevard Jean Moulin, Marseille, 13005 France
| | - Pierre Pontarotti
- Aix Marseille Université, CNRS, Centrale Marseille, I2M UMR 7373, Evolution Biologique et Modélisation, 3 place Victor Hugo, Marseille, 13331 France
| | - Didier Raoult
- Aix Marseille Univ, CNRS, IRD, INSERM, AP-HM URMITE, IHU -Méditerranée Infection, 19-21 Boulevard Jean Moulin, Marseille, 13005 France
| | - Vicky Merhej
- Aix Marseille Univ, CNRS, IRD, INSERM, AP-HM URMITE, IHU -Méditerranée Infection, 19-21 Boulevard Jean Moulin, Marseille, 13005 France
| |
Collapse
|
19
|
Kamneva OK. Genome composition and phylogeny of microbes predict their co-occurrence in the environment. PLoS Comput Biol 2017; 13:e1005366. [PMID: 28152007 PMCID: PMC5313232 DOI: 10.1371/journal.pcbi.1005366] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 02/16/2017] [Accepted: 01/17/2017] [Indexed: 12/15/2022] Open
Abstract
The genomic information of microbes is a major determinant of their phenotypic properties, yet it is largely unknown to what extent ecological associations between different species can be explained by their genome composition. To bridge this gap, this study introduces two new genome-wide pairwise measures of microbe-microbe interaction. The first (genome content similarity index) quantifies similarity in genome composition between two microbes, while the second (microbe-microbe functional association index) summarizes the topology of a protein functional association network built for a given pair of microbes and quantifies the fraction of network edges crossing organismal boundaries. These new indices are then used to predict co-occurrence between reference genomes from two 16S-based ecological datasets, accounting for phylogenetic relatedness of the taxa. Phylogenetic relatedness was found to be a strong predictor of ecological associations between microbes which explains about 10% of variance in co-occurrence data, but genome composition was found to be a strong predictor as well, it explains up to 4% the variance in co-occurrence when all genomic-based indices are used in combination, even after accounting for evolutionary relationships between the species. On their own, the metrics proposed here explain a larger proportion of variance than previously reported more complex methods that rely on metabolic network comparisons. In summary, results of this study indicate that microbial genomes do indeed contain detectable signal of organismal ecology, and the methods described in the paper can be used to improve mechanistic understanding of microbe-microbe interactions. It is still unknown to what extent ecological associations between microbes, as measured by co-occurrence of different taxa in 16S rRNA surveys, can be explained, or predicted, using composition and structure of microbial genomes alone. Here I introduce two new genome-wide, pairwise indices for quantifying the propensity of microbial species to interact with each other. The first measure quantifies similarity in genome composition between two microbes. The second measure summarizes the topology of a protein functional association network built for a given pair of microbes and quantifies the fraction of network edges crossing organismal boundaries. I then study the ability of two newly proposed and two previously reported indices to explain variation in microbial co-occurrence. All four measures are significantly correlated with co-occurrence of microbes even when accounting for evolutionary relationships between the species. One of the newly developed indices outperforms previously proposed ones and explains up to 3.5% of the variance in co-occurrence. In summary, the indices described here are able to detect ecological associations between species using only their genomic information; however, additional methods are needed to provide more reliable genomic tools for microbial ecology.
Collapse
Affiliation(s)
- Olga K. Kamneva
- Department of Biology, Stanford University, Stanford, California, United States of America
- * E-mail:
| |
Collapse
|
20
|
Gonçalves IR, Brouillet S, Soulié MC, Gribaldo S, Sirven C, Charron N, Boccara M, Choquer M. Genome-wide analyses of chitin synthases identify horizontal gene transfers towards bacteria and allow a robust and unifying classification into fungi. BMC Evol Biol 2016; 16:252. [PMID: 27881071 PMCID: PMC5122149 DOI: 10.1186/s12862-016-0815-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 10/28/2016] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Chitin, the second most abundant biopolymer on earth after cellulose, is found in probably all fungi, many animals (mainly invertebrates), several protists and a few algae, playing an essential role in the development of many of them. This polysaccharide is produced by type 2 glycosyltransferases, called chitin synthases (CHS). There are several contradictory classifications of CHS isoenzymes and, as regards their evolutionary history, their origin and diversity is still a matter of debate. RESULTS A genome-wide analysis resulted in the detection of more than eight hundred putative chitin synthases in proteomes associated with about 130 genomes. Phylogenetic analyses were performed with special care to avoid any pitfalls associated with the peculiarities of these sequences (e.g. highly variable regions, truncated or recombined sequences, long-branch attraction). This allowed us to revise and unify the fungal CHS classification and to study the evolutionary history of the CHS multigenic family. This update has the advantage of being user-friendly due to the development of a dedicated website ( http://wwwabi.snv.jussieu.fr/public/CHSdb ), and it includes any correspondences with previously published classifications and mutants. Concerning the evolutionary history of CHS, this family has mainly evolved via duplications and losses. However, it is likely that several horizontal gene transfers (HGT) also occurred in eukaryotic microorganisms and, even more surprisingly, in bacteria. CONCLUSIONS This comprehensive multi-species analysis contributes to the classification of fungal CHS, in particular by optimizing its robustness, consensuality and accessibility. It also highlights the importance of HGT in the evolutionary history of CHS and describes bacterial chs genes for the first time. Many of the bacteria that have acquired a chitin synthase are plant pathogens (e.g. Dickeya spp; Pectobacterium spp; Brenneria spp; Agrobacterium vitis and Pseudomonas cichorii). Whether they are able to produce a chitin exopolysaccharide or secrete chitooligosaccharides requires further investigation.
Collapse
Affiliation(s)
- Isabelle R Gonçalves
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Microbiologie Adaptation et Pathogénie, Bâtiment André Lwoff, 10 rue Raphaël Dubois, F-69622, Villeurbanne, France. .,BAYER S.A.S., Centre de Recherche de la Dargoire, F-69263, Lyon, France.
| | - Sophie Brouillet
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7205 (MNHN, UPMC, CNRS, EPHE), Atelier de Bioinformatique, F-75231, Paris, Cedex 05, France
| | - Marie-Christine Soulié
- Sorbonne Universités, UPMC Univ Paris 06, INRA-AgroParisTech UMR1318, F-78026, Versailles, France
| | - Simonetta Gribaldo
- Institut Pasteur, Unité Biologie Moléculaire du Gène chez les Extrêmophiles, Département de Microbiologie, 25 rue du Docteur Roux, F-75015, Paris, France
| | - Catherine Sirven
- BAYER S.A.S., Centre de Recherche de la Dargoire, F-69263, Lyon, France
| | - Noémie Charron
- BAYER S.A.S., Centre de Recherche de la Dargoire, F-69263, Lyon, France
| | - Martine Boccara
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7205 (MNHN, UPMC, CNRS, EPHE), Atelier de Bioinformatique, F-75231, Paris, Cedex 05, France
| | - Mathias Choquer
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Microbiologie Adaptation et Pathogénie, Bâtiment André Lwoff, 10 rue Raphaël Dubois, F-69622, Villeurbanne, France.,BAYER S.A.S., Centre de Recherche de la Dargoire, F-69263, Lyon, France
| |
Collapse
|
21
|
Gómez-Gallego C, Pohl S, Salminen S, De Vos W, Kneifel W. Akkermansia muciniphila: a novel functional microbe with probiotic properties. Benef Microbes 2016; 7:571-84. [DOI: 10.3920/bm2016.0009] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Akkermansia muciniphila is an intestinal anaerobe which has been proposed as a new functional microbe with probiotic properties. However, the species is not included in the European Union qualified presumption of safety (QPS) list and has not yet been assessed. Moreover, products containing A. muciniphila are not on the market and are thus controlled by the Novel Foods Regulation, which requires extensive safety assessment. This review addresses the safety aspects of the use of A. muciniphila based on published information on its functions in humans and predictions based on its activity in model animals. Further, comprehensive studies related to A. muciniphila and its safety properties have gradually appeared and are summarised here. Many of the criteria required for novel food safety assessment in Europe can thus be fulfilled. However, studies focusing on the toxicological properties of A. muciniphila, including long-term and reproduction studies, have not so far been reported and are discussed in the light of the observation that most, if not all, healthy subjects are known to carry this intestinal anaerobe. As this also applies to other beneficial bacteria found in the human intestinal tract, the A. muciniphila case can be seen as a model for the comprehensive safety evaluations required by the European authorities.
Collapse
Affiliation(s)
- C. Gómez-Gallego
- Functional Foods Forum, Faculty of Medicine, University of Turku, 20014 Turku, Finland
| | - S. Pohl
- Department of Food Sciences and Technology, University of Natural Resources and Life Science Vienna, 1190 Vienna, Austria
| | - S. Salminen
- Functional Foods Forum, Faculty of Medicine, University of Turku, 20014 Turku, Finland
| | - W.M. De Vos
- Laboratory of Microbiology, Wageningen University, 6703 CT, Wageningen, the Netherlands
- RPU Immunobiology, University of Helsinki, 00140 Helsinki, Finland
| | - W. Kneifel
- Department of Food Sciences and Technology, University of Natural Resources and Life Science Vienna, 1190 Vienna, Austria
| |
Collapse
|
22
|
Bertelli C, Cissé OH, Rusconi B, Kebbi-Beghdadi C, Croxatto A, Goesmann A, Collyn F, Greub G. CRISPR System Acquisition and Evolution of an Obligate Intracellular Chlamydia-Related Bacterium. Genome Biol Evol 2016; 8:2376-86. [PMID: 27516530 PMCID: PMC5010888 DOI: 10.1093/gbe/evw138] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Recently, a new Chlamydia-related organism, Protochlamydia naegleriophila KNic, was discovered within a Naegleria amoeba. To decipher the mechanisms at play in the modeling of genomes from the Protochlamydia genus, we sequenced the full genome of Pr. naegleriophila, which includes a 2,885,090 bp chromosome and a 145,285 bp megaplasmid. For the first time within the Chlamydiales order, we describe the presence of a clustered regularly interspaced short palindromic repeats (CRISPR) system, the immune system of bacteria, located on the chromosome. It is composed of a small CRISPR locus comprising eight repeats and associated cas-cse genes of the subtype I-E. A CRISPR locus is also present within Chlamydia sp. Diamant, another Pr. naegleriophila strain, suggesting that the CRISPR system was acquired by a common ancestor of Pr. naegleriophila, after its divergence from Pr. amoebophila. Both nucleotide bias and comparative genomics approaches identified probable horizontal gene acquisitions within two and four genomic islands in Pr. naegleriophila KNic and Diamant genomes, respectively. The plasmid encodes an F-type conjugative system highly similar to 1) that found in the Pam100G genomic island of Pr. amoebophila UWE25 chromosome, as well as on the plasmid of Rubidus massiliensis and 2) to the three genes remaining in the chromosome of Parachlamydia acanthamoebae strains. Therefore, this conjugative system was likely acquired on an ancestral plasmid before the divergence of Parachlamydiaceae Overall, this new complete Pr. naegleriophila genome sequence enables further investigation of the dynamic processes shaping the genomes of the family Parachlamydiaceae and the genus Protochlamydia.
Collapse
Affiliation(s)
- Claire Bertelli
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Ousmane H Cissé
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland
| | - Brigida Rusconi
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland
| | - Carole Kebbi-Beghdadi
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland
| | - Antony Croxatto
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland
| | - Alexander Goesmann
- Bioinformatics and Systems Biology, Justus-Liebig-University Giessen, Germany
| | - François Collyn
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland
| | - Gilbert Greub
- Center for Research on Intracellular Bacteria, Institute of Microbiology, University Hospital Center and University of Lausanne, Switzerland
| |
Collapse
|
23
|
Pinos S, Pontarotti P, Raoult D, Baudoin JP, Pagnier I. Compartmentalization in PVC super-phylum: evolution and impact. Biol Direct 2016; 11:38. [PMID: 27507008 PMCID: PMC4977879 DOI: 10.1186/s13062-016-0144-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 08/02/2016] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND The PVC super-phylum gathers bacteria from seven phyla (Planctomycetes, Verrucomicrobiae, Chlamydiae, Lentisphaera, Poribacteria, OP3, WWE2) presenting different lifestyles, cell plans and environments. Planctomyces and several Verrucomicrobiae exhibit a complex cell plan, with an intracytoplasmic membrane inducing the compartmentalization of the cytoplasm into two regions (pirellulosome and paryphoplasm). The evolution and function of this cell plan is still subject to debate. In this work, we hypothesized that it could play a role in protection of the bacterial DNA, especially against Horizontal Genes Transfers (HGT). Therefore, 64 bacterial genomes belonging to seven different phyla (whose four PVC phyla) were studied. We reconstructed the evolution of the cell plan as precisely as possible, thanks to information obtained by bibliographic study and electronic microscopy. We used a strategy based on comparative phylogenomic in order to determine the part occupied by the horizontal transfers for each studied genomes. RESULTS Our results show that the bacteria Simkania negevensis (Chlamydiae) and Coraliomargarita akajimensis (Verrucomicrobiae), whose cell plan were unknown before, are compartmentalized, as we can see on the micrographies. This is one of the first indication of the presence of an intracytoplasmic membrane in a Chlamydiae. The proportion of HGT does not seems to be related to the cell plan of bacteria, suggesting that compartmentalization does not induce a protection of bacterial DNA against HGT. Conversely, lifestyle of bacteria seems to impact the ability of bacteria to exchange genes. CONCLUSIONS Our study allows a best reconstruction of the evolution of intracytoplasmic membrane, but this structure seems to have no impact on HGT occurrences. REVIEWERS This article was reviewed by Mircea Podar and Olivier Tenaillon.
Collapse
Affiliation(s)
- Sandrine Pinos
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, INSERM 1095, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
- Aix Marseille Université, CNRS, Centrale Marseille, I2M UMR 7373, Evolution Biologique et Modélisation, 13385 Marseille, Cedex 5, France
| | - Pierre Pontarotti
- Aix Marseille Université, CNRS, Centrale Marseille, I2M UMR 7373, Evolution Biologique et Modélisation, 13385 Marseille, Cedex 5, France
| | - Didier Raoult
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, INSERM 1095, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Jean Pierre Baudoin
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, INSERM 1095, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Isabelle Pagnier
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, INSERM 1095, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| |
Collapse
|
24
|
Ottman N, Huuskonen L, Reunanen J, Boeren S, Klievink J, Smidt H, Belzer C, de Vos WM. Characterization of Outer Membrane Proteome of Akkermansia muciniphila Reveals Sets of Novel Proteins Exposed to the Human Intestine. Front Microbiol 2016; 7:1157. [PMID: 27507967 PMCID: PMC4960237 DOI: 10.3389/fmicb.2016.01157] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 07/12/2016] [Indexed: 12/26/2022] Open
Abstract
Akkermansia muciniphila is a common member of the human gut microbiota and belongs to the Planctomycetes-Verrucomicrobia-Chlamydiae superphylum. Decreased levels of A. muciniphila have been associated with many diseases, and thus it is considered to be a beneficial resident of the intestinal mucus layer. Surface-exposed molecules produced by this organism likely play important roles in colonization and communication with other microbes and the host, but the protein composition of the outer membrane (OM) has not been characterized thus far. Herein we set out to identify and characterize A. muciniphila proteins using an integrated approach of proteomics and computational analysis. Sarkosyl extraction and sucrose density-gradient centrifugation methods were used to enrich and fractionate the OM proteome of A. muciniphila. Proteins from these fractions were identified by LC-MS/MS and candidates for OM proteins derived from the experimental approach were subjected to computational screening to verify their location in the cell. In total we identified 79 putative OM and membrane-associated extracellular proteins, and 23 of those were found to differ in abundance between cells of A. muciniphila grown on the natural substrate, mucin, and those grown on the non-mucus sugar, glucose. The identified OM proteins included highly abundant proteins involved in secretion and transport, as well as proteins predicted to take part in formation of the pili-like structures observed in A. muciniphila. The most abundant OM protein was a 95-kD protein, termed PilQ, annotated as a type IV pili secretin and predicted to be involved in the production of pili in A. muciniphila. To verify its location we purified the His-Tag labeled N-terminal domain of PilQ and generated rabbit polyclonal antibodies. Immunoelectron microscopy of thin sections immunolabeled with these antibodies demonstrated the OM localization of PilQ, testifying for its predicted function as a type IV pili secretin in A. muciniphila. As pili structures are known to be involved in the modulation of host immune responses, this provides support for the involvement of OM proteins in the host interaction of A. muciniphila. In conclusion, the characterization of A. muciniphila OM proteome provides valuable information that can be used for further functional and immunological studies.
Collapse
Affiliation(s)
- Noora Ottman
- Laboratory of Microbiology, Wageningen UniversityWageningen, Netherlands; Metapopulation Research Centre, University of HelsinkiHelsinki, Finland
| | - Laura Huuskonen
- Department of Veterinary Biosciences, University of Helsinki Helsinki, Finland
| | - Justus Reunanen
- Department of Veterinary Biosciences, University of HelsinkiHelsinki, Finland; Microbiology and Biotechnology, Department of Food and Environmental Sciences, University of HelsinkiHelsinki, Finland
| | - Sjef Boeren
- Laboratory of Biochemistry, Wageningen University Wageningen, Netherlands
| | - Judith Klievink
- Immunobiology, Department of Bacteriology and Immunology, and Research Programs Unit, University of Helsinki Helsinki, Finland
| | - Hauke Smidt
- Laboratory of Microbiology, Wageningen University Wageningen, Netherlands
| | - Clara Belzer
- Laboratory of Microbiology, Wageningen University Wageningen, Netherlands
| | - Willem M de Vos
- Laboratory of Microbiology, Wageningen UniversityWageningen, Netherlands; Department of Veterinary Biosciences, University of HelsinkiHelsinki, Finland; Immunobiology, Department of Bacteriology and Immunology, and Research Programs Unit, University of HelsinkiHelsinki, Finland
| |
Collapse
|
25
|
Erill I, Campoy S, Kılıç S, Barbé J. The Verrucomicrobia LexA-Binding Motif: Insights into the Evolutionary Dynamics of the SOS Response. Front Mol Biosci 2016; 3:33. [PMID: 27489856 PMCID: PMC4951493 DOI: 10.3389/fmolb.2016.00033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 07/04/2016] [Indexed: 12/20/2022] Open
Abstract
The SOS response is the primary bacterial mechanism to address DNA damage, coordinating multiple cellular processes that include DNA repair, cell division, and translesion synthesis. In contrast to other regulatory systems, the composition of the SOS genetic network and the binding motif of its transcriptional repressor, LexA, have been shown to vary greatly across bacterial clades, making it an ideal system to study the co-evolution of transcription factors and their regulons. Leveraging comparative genomics approaches and prior knowledge on the core SOS regulon, here we define the binding motif of the Verrucomicrobia, a recently described phylum of emerging interest due to its association with eukaryotic hosts. Site directed mutagenesis of the Verrucomicrobium spinosum recA promoter confirms that LexA binds a 14 bp palindromic motif with consensus sequence TGTTC-N4-GAACA. Computational analyses suggest that recognition of this novel motif is determined primarily by changes in base-contacting residues of the third alpha helix of the LexA helix-turn-helix DNA binding motif. In conjunction with comparative genomics analysis of the LexA regulon in the Verrucomicrobia phylum, electrophoretic shift assays reveal that LexA binds to operators in the promoter region of DNA repair genes and a mutagenesis cassette in this organism, and identify previously unreported components of the SOS response. The identification of tandem LexA-binding sites generating instances of other LexA-binding motifs in the lexA gene promoter of Verrucomicrobia species leads us to postulate a novel mechanism for LexA-binding motif evolution. This model, based on gene duplication, successfully addresses outstanding questions in the intricate co-evolution of the LexA protein, its binding motif and the regulatory network it controls.
Collapse
Affiliation(s)
- Ivan Erill
- Erill Lab, Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Susana Campoy
- Unitat de Microbiologia, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona Barcelona, Spain
| | - Sefa Kılıç
- Erill Lab, Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Jordi Barbé
- Unitat de Microbiologia, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona Barcelona, Spain
| |
Collapse
|
26
|
Abstract
Regulation of gene expression ensures an organism responds to stimuli and undergoes proper development. Although the regulatory networks in bacteria have been investigated in model microorganisms, nearly nothing is known about the evolution and plasticity of these networks in obligate, intracellular bacteria. The phylum Chlamydiae contains a vast array of host-associated microbes, including several human pathogens. The Chlamydiae are unique among obligate, intracellular bacteria as they undergo a complex biphasic developmental cycle in which large swaths of genes are temporally regulated. Coupled with the low number of transcription factors, these organisms offer a model to study the evolution of regulatory networks in intracellular organisms. We provide the first comprehensive analysis exploring the diversity and evolution of regulatory networks across the phylum. We utilized a comparative genomics approach to construct predicted coregulatory networks, which unveiled genus- and family-specific regulatory motifs and architectures, most notably those of virulence-associated genes. Surprisingly, our analysis suggests that few regulatory components are conserved across the phylum, and those that are conserved are involved in the exploitation of the intracellular niche. Our study thus lends insight into a component of chlamydial evolution that has otherwise remained largely unexplored.
Collapse
Affiliation(s)
- D Domman
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - M Horn
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| |
Collapse
|
27
|
A phylogenomic and molecular markers based analysis of the phylum Chlamydiae: proposal to divide the class Chlamydiia into two orders, Chlamydiales and Parachlamydiales ord. nov., and emended description of the class Chlamydiia. Antonie van Leeuwenhoek 2015; 108:765-81. [PMID: 26179278 DOI: 10.1007/s10482-015-0532-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 07/10/2015] [Indexed: 12/27/2022]
Abstract
The phylum Chlamydiae contains nine ecologically and genetically diverse families all placed within a single order. In this work, we have completed a comprehensive comparative analysis of 36 sequenced Chlamydiae genomes in order to identify shared molecular characteristics, namely conserved signature insertions/deletions (CSIs) and conserved signature proteins (CSPs), which can serve as distinguishing characteristics of supra-familial clusters within the phylum Chlamydiae. Our analysis has led to the identification of 32 CSIs which are specific to clusters within the phylum Chlamydiae at various phylogenetic depths. Importantly, 17 CSIs and 98 CSPs were found to be specific for the family Chlamydiaceae while another 3 CSI variants and 15 CSPs were specific for a grouping of the families Criblamydiaceae, Parachlamydiaceae, Simkaniaceae and Waddliaceae. These two clusters were also found to be distinguishable in 16S rRNA based phylogenetic trees, concatenated protein based phylogenetic trees, character compatibility based phylogenetic analyses, and on the basis of 16S rRNA gene sequence identity and average amino acid identity values. On the basis of the identified molecular characteristics, branching in phylogenetic trees, and the genetic distance between the two clusters within the phylum Chlamydiae we propose a division of the class Chlamydiia into two orders: an emended order Chlamydiales, containing the family Chlamydiaceae and the closely related Candidatus family Clavichlamydiaceae, and the novel order Parachlamydiales ord. nov. containing the families Parachlamydiaceae, Simkaniaceae and Waddliaceae and the Candidatus families Criblamydiaceae, Parilichlamydiaceae, Piscichlamydiaceae, and Rhabdochlamydiaceae. We also include a brief discussion of the reunification of the genera Chlamydia and Chlamydophila.
Collapse
|
28
|
Kamneva OK, Poudel S, Ward NL. Proteins Related to the Type I Secretion System Are Associated with Secondary SecA_DEAD Domain Proteins in Some Species of Planctomycetes, Verrucomicrobia, Proteobacteria, Nitrospirae and Chlorobi. PLoS One 2015; 10:e0129066. [PMID: 26030905 PMCID: PMC4452313 DOI: 10.1371/journal.pone.0129066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 05/04/2015] [Indexed: 01/09/2023] Open
Abstract
A number of bacteria belonging to the PVC (Planctomycetes-Verrucomicrobia-Chlamydiae) super-phylum contain unusual ribosome-bearing intracellular membranes. The evolutionary origins and functions of these membranes are unknown. Some proteins putatively associated with the presence of intracellular membranes in PVC bacteria contain signal peptides. Signal peptides mark proteins for translocation across the cytoplasmic membrane in prokaryotes, and the membrane of the endoplasmic reticulum in eukaryotes, by highly conserved Sec machinery. This suggests that proteins might be targeted to intracellular membranes in PVC bacteria via the Sec pathway. Here, we show that canonical signal peptides are significantly over-represented in proteins preferentially present in PVC bacteria possessing intracellular membranes, indicating involvement of Sec translocase in their cellular targeting. We also characterized Sec proteins using comparative genomics approaches, focusing on the PVC super-phylum. While we were unable to detect unique changes in Sec proteins conserved among membrane-bearing PVC species, we identified (1) SecA ATPase domain re-arrangements in some Planctomycetes, and (2) secondary SecA_DEAD domain proteins in the genomes of some Planctomycetes, Verrucomicrobia, Proteobacteria, Nitrospirae and Chlorobi. This is the first report of potentially duplicated SecA in Gram-negative bacteria. The phylogenetic distribution of secondary SecA_DEAD domain proteins suggests that the presence of these proteins is not related to the occurrence of PVC endomembranes. Further genomic analysis showed that secondary SecA_DEAD domain proteins are located within genomic neighborhoods that also encode three proteins possessing domains specific for the Type I secretion system.
Collapse
Affiliation(s)
- Olga K. Kamneva
- Department of Biology, Stanford University, Stanford, CA, 94305–5020, United States of America
| | - Saroj Poudel
- Computer Science Department, Montana State University, Bozeman, MT, 59717, United States of America
| | - Naomi L. Ward
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, United States of America
- Department of Botany, University of Wyoming, Laramie, WY, 82071, United States of America
- Program in Ecology, University of Wyoming, Laramie, WY, 82071, United States of America
| |
Collapse
|
29
|
Richards VP, Palmer SR, Pavinski Bitar PD, Qin X, Weinstock GM, Highlander SK, Town CD, Burne RA, Stanhope MJ. Phylogenomics and the dynamic genome evolution of the genus Streptococcus. Genome Biol Evol 2015; 6:741-53. [PMID: 24625962 PMCID: PMC4007547 DOI: 10.1093/gbe/evu048] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The genus Streptococcus comprises important pathogens that have a severe impact on human health and are responsible for substantial economic losses to agriculture. Here, we utilize 46 Streptococcus genome sequences (44 species), including eight species sequenced here, to provide the first genomic level insight into the evolutionary history and genetic basis underlying the functional diversity of all major groups of this genus. Gene gain/loss analysis revealed a dynamic pattern of genome evolution characterized by an initial period of gene gain followed by a period of loss, as the major groups within the genus diversified. This was followed by a period of genome expansion associated with the origins of the present extant species. The pattern is concordant with an emerging view that genomes evolve through a dynamic process of expansion and streamlining. A large proportion of the pan-genome has experienced lateral gene transfer (LGT) with causative factors, such as relatedness and shared environment, operating over different evolutionary scales. Multiple gene ontology terms were significantly enriched for each group, and mapping terms onto the phylogeny showed that those corresponding to genes born on branches leading to the major groups represented approximately one-fifth of those enriched. Furthermore, despite the extensive LGT, several biochemical characteristics have been retained since group formation, suggesting genomic cohesiveness through time, and that these characteristics may be fundamental to each group. For example, proteolysis: mitis group; urea metabolism: salivarius group; carbohydrate metabolism: pyogenic group; and transcription regulation: bovis group.
Collapse
Affiliation(s)
- Vincent P Richards
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Sachse K, Bavoil PM, Kaltenboeck B, Stephens RS, Kuo CC, Rosselló-Móra R, Horn M. Emendation of the family Chlamydiaceae: proposal of a single genus, Chlamydia, to include all currently recognized species. Syst Appl Microbiol 2015; 38:99-103. [PMID: 25618261 DOI: 10.1016/j.syapm.2014.12.004] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 12/22/2014] [Accepted: 12/27/2014] [Indexed: 01/29/2023]
Abstract
The family Chlamydiaceae (order Chlamydiales, phylum Chlamydiae) comprises important, obligate intracellular bacterial pathogens of humans and animals. Subdivision of the family into the two genera Chlamydia and Chlamydophila has been discussed controversially during the past decade. Here, we have revisited the current classification in the light of recent genomic data and in the context of the unique biological properties of these microorganisms. We conclude that neither generally used 16S rRNA sequence identity cut-off values nor parameters based on genomic similarity consistently separate the two genera. Notably, no easily recognizable phenotype such as host preference or tissue tropism is available that would support a subdivision. In addition, the genus Chlamydophila is currently not well accepted and not used by a majority of research groups in the field. Therefore, we propose the classification of all 11 currently recognized Chlamydiaceae species in a single genus, the genus Chlamydia. Finally, we provide emended descriptions of the family Chlamydiaceae, the genus Chlamydia, as well as the species Chlamydia abortus, Chlamydia caviae and Chlamydia felis.
Collapse
Affiliation(s)
- Konrad Sachse
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
| | - Patrik M Bavoil
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, USA
| | - Bernhard Kaltenboeck
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Richard S Stephens
- Program in Infectious Diseases, University of California, Berkeley, CA, USA
| | | | - Ramon Rosselló-Móra
- Mediterranean Institute for Advanced studies (IMEDEA, CSIC-UIB), Esporles, Illes Balears, Spain
| | - Matthias Horn
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| |
Collapse
|
31
|
Domman D, Collingro A, Lagkouvardos I, Gehre L, Weinmaier T, Rattei T, Subtil A, Horn M. Massive expansion of Ubiquitination-related gene families within the Chlamydiae. Mol Biol Evol 2014; 31:2890-904. [PMID: 25069652 PMCID: PMC4209131 DOI: 10.1093/molbev/msu227] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Gene loss, gain, and transfer play an important role in shaping the genomes of all organisms; however, the interplay of these processes in isolated populations, such as in obligate intracellular bacteria, is less understood. Despite a general trend towards genome reduction in these microbes, our phylogenomic analysis of the phylum Chlamydiae revealed that within the family Parachlamydiaceae, gene family expansions have had pronounced effects on gene content. We discovered that the largest gene families within the phylum are the result of rapid gene birth-and-death evolution. These large gene families are comprised of members harboring eukaryotic-like ubiquitination-related domains, such as F-box and BTB-box domains, marking the largest reservoir of these proteins found among bacteria. A heterologous type III secretion system assay suggests that these proteins function as effectors manipulating the host cell. The large disparity in copy number of members in these families between closely related organisms suggests that nonadaptive processes might contribute to the evolution of these gene families. Gene birth-and-death evolution in concert with genomic drift might represent a previously undescribed mechanism by which isolated bacterial populations diversify.
Collapse
Affiliation(s)
- Daryl Domman
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Astrid Collingro
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Ilias Lagkouvardos
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Lena Gehre
- Unité de Biologie des Interactions Cellulaires, Institut Pasteur, Paris, France
| | - Thomas Weinmaier
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Thomas Rattei
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Agathe Subtil
- Unité de Biologie des Interactions Cellulaires, Institut Pasteur, Paris, France
| | - Matthias Horn
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| |
Collapse
|
32
|
Characterization of a planctomycetal organelle: a novel bacterial microcompartment for the aerobic degradation of plant saccharides. Appl Environ Microbiol 2014; 80:2193-205. [PMID: 24487526 DOI: 10.1128/aem.03887-13] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Bacterial microcompartments (BMCs) are organelles that encapsulate functionally linked enzymes within a proteinaceous shell. The prototypical example is the carboxysome, which functions in carbon fixation in cyanobacteria and some chemoautotrophs. It is increasingly apparent that diverse heterotrophic bacteria contain BMCs that are involved in catabolic reactions, and many of the BMCs are predicted to have novel functions. However, most of these putative organelles have not been experimentally characterized. In this study, we sought to discover the function of a conserved BMC gene cluster encoded in the majority of the sequenced planctomycete genomes. This BMC is especially notable for its relatively simple genetic composition, its remote phylogenetic position relative to characterized BMCs, and its apparent exclusivity to the enigmatic Verrucomicrobia and Planctomycetes. Members of the phylum Planctomycetes are known for their morphological dissimilarity to the rest of the bacterial domain: internal membranes, reproduction by budding, and lack of peptidoglycan. As a result, they are ripe for many discoveries, but currently the tools for genetic studies are very limited. We expanded the genetic toolbox for the planctomycetes and generated directed gene knockouts of BMC-related genes in Planctomyces limnophilus. A metabolic activity screen revealed that BMC gene products are involved in the degradation of a number of plant and algal cell wall sugars. Among these sugars, we confirmed that BMCs are formed and required for growth on l-fucose and l-rhamnose. Our results shed light on the functional diversity of BMCs as well as their ecological role in the planctomycetes, which are commonly associated with algae.
Collapse
|
33
|
Subtil A, Collingro A, Horn M. Tracing the primordial Chlamydiae: extinct parasites of plants? TRENDS IN PLANT SCIENCE 2014; 19:36-43. [PMID: 24210739 DOI: 10.1016/j.tplants.2013.10.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 10/09/2013] [Accepted: 10/15/2013] [Indexed: 06/02/2023]
Abstract
Chlamydiae are obligate intracellular bacteria found as symbionts and pathogens in a wide range of eukaryotes, including protists, invertebrates, and vertebrates. It was recently proposed that an ancient chlamydial symbiont facilitated the establishment of primary plastids in a tripartite symbiosis with cyanobacteria and early eukaryotes. In this review, we summarize recent advances in understanding of the lifestyle and the evolutionary history of extant Chlamydiae. We reconstruct and describe key features of the ancient chlamydial symbiont. We propose that it was already adapted to an intracellular lifestyle before the emergence of Archaeplastida, and that several observations are compatible with an essential contribution of Chlamydiae to the evolution of algae and plants.
Collapse
Affiliation(s)
- Agathe Subtil
- Institut Pasteur, Unité de Biologie des Interactions Cellulaires, Paris, France; CNRS URA2582, Paris, France.
| | - Astrid Collingro
- University of Vienna, Division of Microbial Ecology, Vienna, Austria
| | - Matthias Horn
- University of Vienna, Division of Microbial Ecology, Vienna, Austria
| |
Collapse
|
34
|
Kamneva OK, Ward NL. Reconciliation Approaches to Determining HGT, Duplications, and Losses in Gene Trees. METHODS IN MICROBIOLOGY 2014. [DOI: 10.1016/bs.mim.2014.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
35
|
Richards VP, Choi SC, Pavinski Bitar PD, Gurjar AA, Stanhope MJ. Transcriptomic and genomic evidence for Streptococcus agalactiae adaptation to the bovine environment. BMC Genomics 2013; 14:920. [PMID: 24369756 PMCID: PMC3890567 DOI: 10.1186/1471-2164-14-920] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 12/21/2013] [Indexed: 11/10/2022] Open
Abstract
Background Streptococcus agalactiae is a major cause of bovine mastitis, which is the dominant health disorder affecting milk production within the dairy industry and is responsible for substantial financial losses to the industry worldwide. However, there is considerable evidence for host adaptation (ecotypes) within S. agalactiae, with both bovine and human sourced isolates showing a high degree of distinctiveness, suggesting differing ability to cause mastitis. Here, we (i) generate RNAseq data from three S. agalactiae isolates (two putative bovine adapted and one human) and (ii) compare publicly available whole genome shotgun sequence data from an additional 202 isolates, obtained from six host species, to elucidate possible genetic factors/adaptations likely important for S. agalactiae growth and survival in the bovine mammary gland. Results Tests for differential expression showed distinct expression profiles for the three isolates when grown in bovine milk. A key finding for the two putatively bovine adapted isolates was the up regulation of a lactose metabolism operon (Lac.2) that was strongly correlated with the bovine environment (all 36 bovine sourced isolates on GenBank possessed the operon, in contrast to only 8/151 human sourced isolates). Multi locus sequence typing of all genome sequences and phylogenetic analysis using conserved operon genes from 44 S. agalactiae isolates and 16 additional Streptococcus species provided strong evidence for acquisition of the operon via multiple lateral gene transfer events, with all Streptococcus species known to be major causes of mastitis, identified as possible donors. Furthermore, lactose fermentation tests were only positive for isolates possessing Lac.2. Combined, these findings suggest that lactose metabolism is likely an important adaptation to the bovine environment. Additional up regulation in the bovine adapted isolates included genes involved in copper homeostasis, metabolism of purine, pyrimidine, glycerol and glucose, and possibly aminoglycoside antibiotic resistance. Conclusion We detected several genetic factors likely important in S. agalactiae’s adaptation to the bovine environment, in particular lactose metabolism. Of concern is the up regulation of a putative antibiotic resistance gene (GCN5-related N-acetyltransferase) that might reflect an adaptation to the use of aminoglycoside antibiotics within this environment.
Collapse
Affiliation(s)
| | | | | | | | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
| |
Collapse
|
36
|
Nakhleh L. Computational approaches to species phylogeny inference and gene tree reconciliation. Trends Ecol Evol 2013; 28:719-28. [PMID: 24094331 PMCID: PMC3855310 DOI: 10.1016/j.tree.2013.09.004] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 09/02/2013] [Accepted: 09/03/2013] [Indexed: 01/20/2023]
Abstract
An intricate relation exists between gene trees and species phylogenies, due to evolutionary processes that act on the genes within and across the branches of the species phylogeny. From an analytical perspective, gene trees serve as character states for inferring accurate species phylogenies, and species phylogenies serve as a backdrop against which gene trees are contrasted for elucidating evolutionary processes and parameters. In a 1997 paper, Maddison discussed this relation, reviewed the signatures left by three major evolutionary processes on the gene trees, and surveyed parsimony and likelihood criteria for utilizing these signatures to elucidate computationally this relation. Here, I review progress that has been made in developing computational methods for analyses under these two criteria, and survey remaining challenges.
Collapse
Affiliation(s)
- Luay Nakhleh
- Department of Computer Science, Rice University, Houston, TX 77005, USA; Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA.
| |
Collapse
|
37
|
Pilhofer M, Aistleitner K, Ladinsky MS, König L, Horn M, Jensen GJ. Architecture and host interface of environmental chlamydiae revealed by electron cryotomography. Environ Microbiol 2013; 16:417-29. [PMID: 24118768 PMCID: PMC4949044 DOI: 10.1111/1462-2920.12299] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 09/26/2013] [Indexed: 01/14/2023]
Abstract
Chlamydiae comprise important pathogenic and symbiotic bacteria that alternate between morphologically and physiologically different life stages during their developmental cycle. Using electron cryotomography, we characterize the ultrastructure of the developmental stages of three environmental chlamydiae: Parachlamydia acanthamoebae, Protochlamydia amoebophila and Simkania negevensis. We show that chemical fixation and dehydration alter the cell shape of Parachlamydia and that the crescent body is not a developmental stage, but an artefact of conventional electron microscopy. We further reveal type III secretion systems of environmental chlamydiae at macromolecular resolution and find support for a chlamydial needle-tip protein. Imaging bacteria inside their host cells by cryotomography for the first time, we observe marked differences in inclusion morphology and development as well as host organelle recruitment between the three chlamydial organisms, with Simkania inclusions being tightly enveloped by the host endoplasmic reticulum. The study demonstrates the power of electron cryotomography to reveal structural details of bacteria-host interactions that are not accessible using traditional methods.
Collapse
Affiliation(s)
- Martin Pilhofer
- Division of Biology, California Institute of Technology, Pasadena, CA, 91125, USA; Howard Hughes Medical Institute, Pasadena, CA, 91125, USA
| | | | | | | | | | | |
Collapse
|
38
|
Abstract
The phyla Planctomycetes, Verrucomicrobia, Chlamydiae, Lentisphaerae, and "Candidatus Omnitrophica (OP3)" comprise bacteria that share an ancestor but show highly diverse biological and ecological features. Together, they constitute the PVC superphylum. Using large-scale comparative genome sequence analysis, we identified a protein uniquely shared among all of the known members of the PVC superphylum. We provide evidence that this signature protein is expressed by representative members of the PVC superphylum. Its predicted structure, physicochemical characteristics, and overexpression in Escherichia coli and gel retardation assays with purified signature protein suggest a housekeeping function with unspecific DNA/RNA binding activity. Phylogenetic analysis demonstrated that the signature protein is a suitable phylogenetic marker for members of the PVC superphylum, and the screening of published metagenome data indicated the existence of additional PVC members. This study provides further evidence of a common evolutionary history of the PVC superphylum and presents a unique case in which a single protein serves as an evolutionary link among otherwise highly diverse members of major bacterial groups.
Collapse
|
39
|
Lagkouvardos I, Weinmaier T, Lauro FM, Cavicchioli R, Rattei T, Horn M. Integrating metagenomic and amplicon databases to resolve the phylogenetic and ecological diversity of the Chlamydiae. ISME JOURNAL 2013; 8:115-25. [PMID: 23949660 DOI: 10.1038/ismej.2013.142] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 07/12/2013] [Accepted: 07/16/2013] [Indexed: 11/09/2022]
Abstract
In the era of metagenomics and amplicon sequencing, comprehensive analyses of available sequence data remain a challenge. Here we describe an approach exploiting metagenomic and amplicon data sets from public databases to elucidate phylogenetic diversity of defined microbial taxa. We investigated the phylum Chlamydiae whose known members are obligate intracellular bacteria that represent important pathogens of humans and animals, as well as symbionts of protists. Despite their medical relevance, our knowledge about chlamydial diversity is still scarce. Most of the nine known families are represented by only a few isolates, while previous clone library-based surveys suggested the existence of yet uncharacterized members of this phylum. Here we identified more than 22,000 high quality, non-redundant chlamydial 16S rRNA gene sequences in diverse databases, as well as 1900 putative chlamydial protein-encoding genes. Even when applying the most conservative approach, clustering of chlamydial 16S rRNA gene sequences into operational taxonomic units revealed an unexpectedly high species, genus and family-level diversity within the Chlamydiae, including 181 putative families. These in silico findings were verified experimentally in one Antarctic sample, which contained a high diversity of novel Chlamydiae. In our analysis, the Rhabdochlamydiaceae, whose known members infect arthropods, represents the most diverse and species-rich chlamydial family, followed by the protist-associated Parachlamydiaceae, and a putative new family (PCF8) with unknown host specificity. Available information on the origin of metagenomic samples indicated that marine environments contain the majority of the newly discovered chlamydial lineages, highlighting this environment as an important chlamydial reservoir.
Collapse
Affiliation(s)
- Ilias Lagkouvardos
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Thomas Weinmaier
- Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Federico M Lauro
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - Ricardo Cavicchioli
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - Thomas Rattei
- Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Matthias Horn
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| |
Collapse
|
40
|
Fuerst JA. The PVC superphylum: exceptions to the bacterial definition? Antonie van Leeuwenhoek 2013; 104:451-66. [PMID: 23912444 DOI: 10.1007/s10482-013-9986-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 07/22/2013] [Indexed: 11/30/2022]
Abstract
The PVC superphylum is a grouping of distinct phyla of the domain bacteria proposed initially on the basis of 16S rRNA gene sequence analysis. It consists of a core of phyla Planctomycetes, Verrucomicrobia and Chlamydiae, but several other phyla have been considered to be members, including phylum Lentisphaerae and several other phyla consisting only of yet-to-be cultured members. The genomics-based links between Planctomycetes, Verrucomicrobia and Chlamydiae have been recently strengthened, but there appear to be other features which may confirm the relationship at least of Planctomycetes, Verrucomicrobia and Lentisphaerae. Remarkably these include the unique planctomycetal compartmentalized cell plan differing from the cell organization typical for bacteria. Such a shared cell plan suggests that the common ancestor of the PVC superphylum members may also have been compartmentalized, suggesting this is an evolutionarily homologous feature at least within the superphylum. Both the PVC endomembranes and the eukaryote-homologous membrane-coating MC proteins linked to endocytosis ability in Gemmata obscuriglobus and shared by PVC members suggest such homology may extend beyond the bacteria to the Eukarya. If so, either our definition of bacteria may have to change or PVC members admitted to be exceptions. The cases for and against considering the PVC superphylum members as exceptions to the bacteria are discussed, and arguments for them as exceptions presented. Recent critical analysis has favoured convergence and analogy for explaining eukaryote-like features in planctomycetes and other PVC organisms. The case is made for constructing hypotheses leaving the possibility of homology and evolutionary links to eukaryote features open. As the case of discovery of endocytosis-like protein uptake in planctomycetes has suggested, this may prove a strong basis for the immediate future of experimental research programs in the PVC scientific community.
Collapse
Affiliation(s)
- John A Fuerst
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia,
| |
Collapse
|
41
|
Abstract
Marine bacteria in the Roseobacter and SAR11 lineages successfully exploit the ocean habitat, together accounting for ~40% of bacteria in surface waters, yet have divergent life histories that exemplify patch-adapted versus free-living ecological roles. Here, we use a phylogenetic birth-and-death model to understand how genome content supporting different life history strategies evolved in these related alphaproteobacterial taxa, showing that the streamlined genomes of free-living SAR11 were gradually downsized from a common ancestral genome only slightly larger than the extant members (~2,000 genes), while the larger and variably sized genomes of roseobacters evolved along dynamic pathways from a sizeable common ancestor (~8,000 genes). Genome changes in the SAR11 lineage occurred gradually over ~800 million years, whereas Roseobacter genomes underwent more substantial modifications, including major periods of expansion, over ~260 million years. The timing of the first Roseobacter genome expansion was coincident with the predicted radiation of modern marine eukaryotic phytoplankton of sufficient size to create nutrient-enriched microzones and is consistent with present-day ecological associations between these microbial groups. We suggest that diversification of red-lineage phytoplankton is an important driver of divergent life history strategies among the heterotrophic bacterioplankton taxa that dominate the present-day ocean. One-half of global primary production occurs in the oceans, and more than half of this is processed by heterotrophic bacterioplankton through the marine microbial food web. The diversity of life history strategies that characterize different bacterioplankton taxa is an important subject, since the locations and mechanisms whereby bacteria interact with seawater organic matter has effects on microbial growth rates, metabolic pathways, and growth efficiencies, and these in turn affect rates of carbon mineralization to the atmosphere and sequestration into the deep sea. Understanding the evolutionary origins of the ecological strategies that underlie biochemical interactions of bacteria with the ocean system, and which scale up to affect globally important biogeochemical processes, will improve understanding of how microbial diversity is maintained and enable useful predictions about microbial response in the future ocean.
Collapse
|