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Minnick MF. Functional Roles and Genomic Impact of Miniature Inverted-Repeat Transposable Elements (MITEs) in Prokaryotes. Genes (Basel) 2024; 15:328. [PMID: 38540387 PMCID: PMC10969869 DOI: 10.3390/genes15030328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 02/27/2024] [Accepted: 03/01/2024] [Indexed: 06/14/2024] Open
Abstract
Prokaryotic genomes are dynamic tapestries that are strongly influenced by mobile genetic elements (MGEs), including transposons (Tn's), plasmids, and bacteriophages. Of these, miniature inverted-repeat transposable elements (MITEs) are undoubtedly the least studied MGEs in bacteria and archaea. This review explores the diversity and distribution of MITEs in prokaryotes and describes what is known about their functional roles in the host and involvement in genomic plasticity and evolution.
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Affiliation(s)
- Michael F Minnick
- Program in Cellular, Molecular and Microbial Biology, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
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2
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Wattam AR, Bowers N, Brettin T, Conrad N, Cucinell C, Davis JJ, Dickerman AW, Dietrich EM, Kenyon RW, Machi D, Mao C, Nguyen M, Olson RD, Overbeek R, Parrello B, Pusch GD, Shukla M, Stevens RL, Vonstein V, Warren AS. Comparative Genomic Analysis of Bacterial Data in BV-BRC: An Example Exploring Antimicrobial Resistance. Methods Mol Biol 2024; 2802:547-571. [PMID: 38819571 DOI: 10.1007/978-1-0716-3838-5_18] [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] [Indexed: 06/01/2024]
Abstract
As genomic and related data continue to expand, research biologists are often hampered by the computational hurdles required to analyze their data. The National Institute of Allergy and Infectious Diseases (NIAID) established the Bioinformatics Resource Centers (BRC) to assist researchers with their analysis of genome sequence and other omics-related data. Recently, the PAThosystems Resource Integration Center (PATRIC), the Influenza Research Database (IRD), and the Virus Pathogen Database and Analysis Resource (ViPR) BRCs merged to form the Bacterial and Viral Bioinformatics Resource Center (BV-BRC) at https://www.bv-brc.org/ . The combined BV-BRC leverages the functionality of the original resources for bacterial and viral research communities with a unified data model, enhanced web-based visualization and analysis tools, and bioinformatics services. Here we demonstrate how antimicrobial resistance data can be analyzed in the new resource.
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Affiliation(s)
- Alice R Wattam
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA.
| | - Nicole Bowers
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Thomas Brettin
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne, IL, USA
| | - Neal Conrad
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Clark Cucinell
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA
| | - James J Davis
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Allan W Dickerman
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA
| | - Emily M Dietrich
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Ronald W Kenyon
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA
| | - Dustin Machi
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA
| | - Chunhong Mao
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA
| | - Marcus Nguyen
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Robert D Olson
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Ross Overbeek
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, USA
| | - Bruce Parrello
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, USA
| | - Gordon D Pusch
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, USA
| | - Maulik Shukla
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Division of Data Science and Learning, Argonne National Laboratory, Argonne, IL, USA
| | - Rick L Stevens
- Department of Computer Science, University of Chicago, Chicago, IL, USA
| | | | - Andrew S Warren
- Biocomplexity Institute, University of Virginia, Charlottesville, VA, USA
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3
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Chan WT, Garcillán-Barcia MP, Yeo CC, Espinosa M. Type II bacterial toxin-antitoxins: hypotheses, facts, and the newfound plethora of the PezAT system. FEMS Microbiol Rev 2023; 47:fuad052. [PMID: 37715317 PMCID: PMC10532202 DOI: 10.1093/femsre/fuad052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/24/2023] [Accepted: 09/07/2023] [Indexed: 09/17/2023] Open
Abstract
Toxin-antitoxin (TA) systems are entities found in the prokaryotic genomes, with eight reported types. Type II, the best characterized, is comprised of two genes organized as an operon. Whereas toxins impair growth, the cognate antitoxin neutralizes its activity. TAs appeared to be involved in plasmid maintenance, persistence, virulence, and defence against bacteriophages. Most Type II toxins target the bacterial translational machinery. They seem to be antecessors of Higher Eukaryotes and Prokaryotes Nucleotide-binding (HEPN) RNases, minimal nucleotidyltransferase domains, or CRISPR-Cas systems. A total of four TAs encoded by Streptococcus pneumoniae, RelBE, YefMYoeB, Phd-Doc, and HicAB, belong to HEPN-RNases. The fifth is represented by PezAT/Epsilon-Zeta. PezT/Zeta toxins phosphorylate the peptidoglycan precursors, thereby blocking cell wall synthesis. We explore the body of knowledge (facts) and hypotheses procured for Type II TAs and analyse the data accumulated on the PezAT family. Bioinformatics analyses showed that homologues of PezT/Zeta toxin are abundantly distributed among 14 bacterial phyla mostly in Proteobacteria (48%), Firmicutes (27%), and Actinobacteria (18%), showing the widespread distribution of this TA. The pezAT locus was found to be mainly chromosomally encoded whereas its homologue, the tripartite omega-epsilon-zeta locus, was found mostly on plasmids. We found several orphan pezT/zeta toxins, unaccompanied by a cognate antitoxin.
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Affiliation(s)
- Wai Ting Chan
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, 9, 28040 Madrid, Spain
| | - Maria Pilar Garcillán-Barcia
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-Consejo Superior de Investigaciones Científicas, C/Albert Einstein 22, PCTCAN, 39011 Santander, Spain
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine
, Universiti Sultan Zainal Abidin, Jalan Sultan Mahumd, 20400 Kuala Terengganu, Malaysia
| | - Manuel Espinosa
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, 9, 28040 Madrid, Spain
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4
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Colombini L, Cuppone AM, Tirziu M, Lazzeri E, Pozzi G, Santoro F, Iannelli F. The Mobilome-Enriched Genome of the Competence-Deficient Streptococcus pneumoniae BM6001, the Original Host of Integrative Conjugative Element Tn 5253, Is Phylogenetically Distinct from Historical Pneumococcal Genomes. Microorganisms 2023; 11:1646. [PMID: 37512819 PMCID: PMC10383233 DOI: 10.3390/microorganisms11071646] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/08/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
Streptococcus pneumoniae is an important human pathogen causing both mild and severe diseases. In this work, we determined the complete genome sequence of the S. pneumoniae clinical isolate BM6001, which is the original host of the ICE Tn5253. The BM6001 genome is organized in one circular chromosome of 2,293,748 base pairs (bp) in length, with an average GC content of 39.54%; the genome harbors a type 19F capsule locus, two tandem copies of pspC, the comC1-comD1 alleles and the type I restriction modification system SpnIII. The BM6001 mobilome accounts for 15.54% (356,521 bp) of the whole genome and includes (i) the ICE Tn5253 composite; (ii) the novel IME Tn7089; (iii) the novel transposon Tn7090; (iv) 3 prophages and 2 satellite prophages; (v) 5 genomic islands (GIs); (vi) 72 insertion sequences (ISs); (vii) 69 RUPs; (viii) 153 BOX elements; and (ix) 31 SPRITEs. All MGEs, except for the GIs, produce excised circular forms and attB site restoration. Tn7089 is 9089 bp long and contains 11 ORFs, of which 6 were annotated and code for three functions: integration/excision, mobilization and adaptation. Tn7090 is 9053 bp in size, flanked by two copies of ISSpn7, and contains seven ORFs organized as a single transcriptional unit, with genes encoding for proteins likely involved in the uptake and binding of Mg2+ cations in the adhesion to host cells and intracellular survival. BM6001 GIs, except for GI-BM6001.4, are variants of the pneumococcal TIGR4 RD5 region of diversity, pathogenicity island PPI1, R6 Cluster 4 and PTS island. Overall, prophages and satellite prophages contain genes predicted to encode proteins involved in DNA replication and lysogeny, in addition to genes encoding phage structural proteins and lytic enzymes carried only by prophages. ΦBM6001.3 has a mosaic structure that shares sequences with prophages IPP69 and MM1 and disrupts the competent comGC/cglC gene after chromosomal integration. Treatment with mitomycin C results in a 10-fold increase in the frequency of ΦBM6001.3 excised forms and comGC/cglC coding sequence restoration but does not restore competence for genetic transformation. In addition, phylogenetic analysis showed that BM6001 clusters in a small lineage with five other historical strains, but it is distantly related to the lineage due to its unique mobilome, suggesting that BM6001 has progressively accumulated many MGEs while losing competence for genetic transformation.
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Affiliation(s)
- Lorenzo Colombini
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
| | - Anna Maria Cuppone
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
| | - Mariana Tirziu
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
| | - Elisa Lazzeri
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
| | - Gianni Pozzi
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
| | - Francesco Santoro
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
| | - Francesco Iannelli
- Laboratory of Molecular Microbiology and Biotechnology (LAMMB), Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, V Lotto I Piano, Viale Bracci, 53100 Siena, Italy
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Glanville DG, Gazioglu O, Marra M, Tokars VL, Kushnir T, Habtom M, Croucher NJ, Nebenzahl YM, Mondragón A, Yesilkaya H, Ulijasz AT. Pneumococcal capsule expression is controlled through a conserved, distal cis-regulatory element during infection. PLoS Pathog 2023; 19:e1011035. [PMID: 36719895 PMCID: PMC9888711 DOI: 10.1371/journal.ppat.1011035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/29/2022] [Indexed: 02/01/2023] Open
Abstract
Streptococcus pneumoniae (the pneumococcus) is the major cause of bacterial pneumonia in the US and worldwide. Studies have shown that the differing chemical make-up between serotypes of its most important virulence factor, the capsule, can dictate disease severity. Here we demonstrate that control of capsule synthesis is also critical for infection and facilitated by two broadly conserved transcription factors, SpxR and CpsR, through a distal cis-regulatory element we name the 37-CE. Strikingly, changing only three nucleotides within this sequence is sufficient to render pneumococcus avirulent. Using in vivo and in vitro approaches, we present a model where SpxR interacts as a unique trimeric quaternary structure with the 37-CE to enable capsule repression in the airways. Considering its dramatic effect on infection, variation of the 37-CE between serotypes suggests this molecular switch could be a critical contributing factor to this pathogen's serotype-specific disease outcomes.
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Affiliation(s)
- David G. Glanville
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Ozcan Gazioglu
- Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom
| | - Michela Marra
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Valerie L. Tokars
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Tatyana Kushnir
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of The Negev, Beer-Sheva, Israel
| | - Medhanie Habtom
- Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom
| | - Nicholas J. Croucher
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Sir Michael Uren Hub, Imperial College London, London, United Kingdom
| | - Yaffa Mizrachi Nebenzahl
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of The Negev, Beer-Sheva, Israel
| | - Alfonso Mondragón
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America
| | - Hasan Yesilkaya
- Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom
| | - Andrew T. Ulijasz
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, United States of America
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6
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Stevens EJ, Morse DJ, Bonini D, Duggan S, Brignoli T, Recker M, Lees JA, Croucher NJ, Bentley S, Wilson DJ, Earle SG, Dixon R, Nobbs A, Jenkinson H, van Opijnen T, Thibault D, Wilkinson OJ, Dillingham MS, Carlile S, McLoughlin RM, Massey RC. Targeted control of pneumolysin production by a mobile genetic element in Streptococcus pneumoniae. Microb Genom 2022; 8:000784. [PMID: 35416147 PMCID: PMC9453066 DOI: 10.1099/mgen.0.000784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Streptococcus pneumoniae is a major human pathogen that can cause severe invasive diseases such as pneumonia, septicaemia and meningitis. Young children are at a particularly high risk, with an estimated 3-4 million cases of severe disease and between 300 000 and 500 000 deaths attributable to pneumococcal disease each year. The haemolytic toxin pneumolysin (Ply) is a primary virulence factor for this bacterium, yet despite its key role in pathogenesis, immune evasion and transmission, the regulation of Ply production is not well defined. Using a genome-wide association approach, we identified a large number of potential affectors of Ply activity, including a gene acquired horizontally on the antibiotic resistance-conferring Integrative and Conjugative Element (ICE) ICESp23FST81. This gene encodes a novel modular protein, ZomB, which has an N-terminal UvrD-like helicase domain followed by two Cas4-like domains with potent ATP-dependent nuclease activity. We found the regulatory effect of ZomB to be specific for the ply operon, potentially mediated by its high affinity for the BOX repeats encoded therein. Using a murine model of pneumococcal colonization, we further demonstrate that a ZomB mutant strain colonizes both the upper respiratory tract and lungs at higher levels when compared to the wild-type strain. While the antibiotic resistance-conferring aspects of ICESp23FST81 are often credited with contributing to the success of the S. pneumoniae lineages that acquire it, its ability to control the expression of a major virulence factor implicated in bacterial transmission is also likely to have played an important role.
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Affiliation(s)
- Emily J Stevens
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Daniel J Morse
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Dora Bonini
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Seána Duggan
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Tarcisio Brignoli
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Mario Recker
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Exeter, TR10 9FE, UK.,Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - John A Lees
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, St. Mary's Campus, Imperial College London, London, W2 1PG, UK
| | - Nicholas J Croucher
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, St. Mary's Campus, Imperial College London, London, W2 1PG, UK
| | - Stephen Bentley
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Daniel J Wilson
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Oxford, OX3 7LF, UK
| | - Sarah G Earle
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Oxford, OX3 7LF, UK
| | - Robert Dixon
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Oxford, OX3 7LF, UK
| | - Angela Nobbs
- Bristol Dental School, University of Bristol, Bristol, BS1 2LY, UK
| | - Howard Jenkinson
- Bristol Dental School, University of Bristol, Bristol, BS1 2LY, UK
| | | | - Derek Thibault
- Biology Department, Boston College, Chestnut Hill, MA, USA
| | - Oliver J Wilkinson
- DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Mark S Dillingham
- DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Simon Carlile
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Rachel M McLoughlin
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Ruth C Massey
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK.,Schools of Microbiology and Medicine and APC Microbiome Ireland, University College Cork, Cork, Ireland
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Interactions of the Streptococcus pneumoniae Toxin-Antitoxin RelBE Proteins with Their Target DNA. Microorganisms 2021; 9:microorganisms9040851. [PMID: 33921033 PMCID: PMC8071376 DOI: 10.3390/microorganisms9040851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 11/17/2022] Open
Abstract
Type II bacterial toxin-antitoxin (TA) systems are found in most bacteria, archaea, and mobile genetic elements. TAs are usually found as a bi-cistronic operon composed of an unstable antitoxin and a stable toxin that targets crucial cellular functions like DNA supercoiling, cell-wall synthesis or mRNA translation. The type II RelBE system encoded by the pathogen Streptococcus pneumoniae is highly conserved among different strains and participates in biofilm formation and response to oxidative stress. Here, we have analyzed the participation of the RelB antitoxin and the RelB:RelE protein complex in the self-regulation of the pneumococcal relBE operon. RelB acted as a weak repressor, whereas RelE performed the role of a co-repressor. By DNA footprinting experiments, we show that the proteins bind to a region that encompasses two palindromic sequences that are located around the -10 sequences of the single promoter that directs the synthesis of the relBE mRNA. High-resolution footprinting assays showed the distribution of bases whose deoxyriboses are protected by the bound proteins, demonstrating that RelB and RelB:RelE contacted the DNA backbone on one face of the DNA helix and that these interactions extended beyond the palindromic sequences. Our findings suggest that the binding of the RelBE proteins to its DNA target would lead to direct inhibition of the binding of the host RNA polymerase to the relBE promoter.
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8
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Dual RNA-seq in Streptococcus pneumoniae Infection Reveals Compartmentalized Neutrophil Responses in Lung and Pleural Space. mSystems 2019; 4:4/4/e00216-19. [PMID: 31409659 PMCID: PMC6697439 DOI: 10.1128/msystems.00216-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The factors that regulate the passage of bacteria between different anatomical compartments are unclear. We have used an experimental model of infection with Streptococcus pneumoniae to examine the host and bacterial factors involved in the passage of bacteria from the lung to the pleural space. The transcriptional profile of host and bacterial cells within the pleural space and lung was analyzed using deep sequencing of the entire transcriptome using the technique of dual RNA-seq. We found significant differences in the host and bacterial RNA profiles in infection, which shed light on the key factors that allow passage of this bacterium into the pleural space. Streptococcus pneumoniae is the dominant cause of community-acquired pneumonia worldwide. Invasion of the pleural space is common and results in increased mortality. We set out to determine the bacterial and host factors that influence invasion of the pleural space. In a murine model of pneumococcal infection, we isolated neutrophil-dominated samples of bronchoalveolar and pleural fluid containing bacteria 48 hours after infection. Using dual RNA sequencing (RNA-seq), we characterized bacterial and host transcripts that were differentially regulated between these compartments and bacteria in broth and resting neutrophils, respectively. Pleural and lung samples showed upregulation of genes involved in the positive regulation of neutrophil extravasation but downregulation of genes mediating bacterial killing. Compared to the lung samples, cells within the pleural space showed marked upregulation of many genes induced by type I interferons, which are cytokines implicated in preventing bacterial transmigration across epithelial barriers. Differences in the bacterial transcripts between the infected samples and bacteria grown in broth showed the upregulation of genes in the bacteriocin locus, the pneumococcal surface adhesin PsaA, and the glycopeptide resistance gene vanZ; the gene encoding the ClpP protease was downregulated in infection. One hundred sixty-nine intergenic putative small bacterial RNAs were also identified, of which 43 (25.4%) small RNAs had been previously described. Forty-two of the small RNAs were upregulated in pleura compared to broth, including many previously identified as being important in virulence. Our results have identified key host and bacterial responses to invasion of the pleural space that can be potentially exploited to develop alternative antimicrobial strategies for the prevention and treatment of pneumococcal pleural disease. IMPORTANCE The factors that regulate the passage of bacteria between different anatomical compartments are unclear. We have used an experimental model of infection with Streptococcus pneumoniae to examine the host and bacterial factors involved in the passage of bacteria from the lung to the pleural space. The transcriptional profile of host and bacterial cells within the pleural space and lung was analyzed using deep sequencing of the entire transcriptome using the technique of dual RNA-seq. We found significant differences in the host and bacterial RNA profiles in infection, which shed light on the key factors that allow passage of this bacterium into the pleural space.
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9
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Slager J, Aprianto R, Veening JW. Deep genome annotation of the opportunistic human pathogen Streptococcus pneumoniae D39. Nucleic Acids Res 2019; 46:9971-9989. [PMID: 30107613 PMCID: PMC6212727 DOI: 10.1093/nar/gky725] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 07/30/2018] [Indexed: 12/27/2022] Open
Abstract
A precise understanding of the genomic organization into transcriptional units and their regulation is essential for our comprehension of opportunistic human pathogens and how they cause disease. Using single-molecule real-time (PacBio) sequencing we unambiguously determined the genome sequence of Streptococcus pneumoniae strain D39 and revealed several inversions previously undetected by short-read sequencing. Significantly, a chromosomal inversion results in antigenic variation of PhtD, an important surface-exposed virulence factor. We generated a new genome annotation using automated tools, followed by manual curation, reflecting the current knowledge in the field. By combining sequence-driven terminator prediction, deep paired-end transcriptome sequencing and enrichment of primary transcripts by Cappable-Seq, we mapped 1015 transcriptional start sites and 748 termination sites. We show that the pneumococcal transcriptional landscape is complex and includes many secondary, antisense and internal promoters. Using this new genomic map, we identified several new small RNAs (sRNAs), RNA switches (including sixteen previously misidentified as sRNAs), and antisense RNAs. In total, we annotated 89 new protein-encoding genes, 34 sRNAs and 165 pseudogenes, bringing the S. pneumoniae D39 repertoire to 2146 genetic elements. We report operon structures and observed that 9% of operons are leaderless. The genome data are accessible in an online resource called PneumoBrowse (https://veeninglab.com/pneumobrowse) providing one of the most complete inventories of a bacterial genome to date. PneumoBrowse will accelerate pneumococcal research and the development of new prevention and treatment strategies.
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Affiliation(s)
- Jelle Slager
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, the Netherlands
| | - Rieza Aprianto
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, the Netherlands
| | - Jan-Willem Veening
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, the Netherlands.,Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
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10
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Abstract
Ninety years after the discovery of pneumococcal Transformation, and 74 years after the work of Avery and colleagues that identified DNA as the genetic material, Streptococcus pneumoniae is still one of the most important model organism to understand Bacterial Genetics and Genomics. In this Chapter special emphasis has been given to Genomics and to Mobile Genetic Elements (the Mobilome) which greatly contribute to the dynamic variation of pneumococcal genomes by horizontal gene transfer. Other topics include molecular mechanisms of Genetic Transformation, Restriction/Modification Systems, Mismatch DNA Repair, and techniques for construction of genetically engineered pneumococcal strains.
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11
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Lees JA, Ferwerda B, Kremer PHC, Wheeler NE, Serón MV, Croucher NJ, Gladstone RA, Bootsma HJ, Rots NY, Wijmega-Monsuur AJ, Sanders EAM, Trzciński K, Wyllie AL, Zwinderman AH, van den Berg LH, van Rheenen W, Veldink JH, Harboe ZB, Lundbo LF, de Groot LCPGM, van Schoor NM, van der Velde N, Ängquist LH, Sørensen TIA, Nohr EA, Mentzer AJ, Mills TC, Knight JC, du Plessis M, Nzenze S, Weiser JN, Parkhill J, Madhi S, Benfield T, von Gottberg A, van der Ende A, Brouwer MC, Barrett JC, Bentley SD, van de Beek D. Joint sequencing of human and pathogen genomes reveals the genetics of pneumococcal meningitis. Nat Commun 2019; 10:2176. [PMID: 31092817 PMCID: PMC6520353 DOI: 10.1038/s41467-019-09976-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 04/11/2019] [Indexed: 12/21/2022] Open
Abstract
Streptococcus pneumoniae is a common nasopharyngeal colonizer, but can also cause life-threatening invasive diseases such as empyema, bacteremia and meningitis. Genetic variation of host and pathogen is known to play a role in invasive pneumococcal disease, though to what extent is unknown. In a genome-wide association study of human and pathogen we show that human variation explains almost half of variation in susceptibility to pneumococcal meningitis and one-third of variation in severity, identifying variants in CCDC33 associated with susceptibility. Pneumococcal genetic variation explains a large amount of invasive potential (70%), but has no effect on severity. Serotype alone is insufficient to explain invasiveness, suggesting other pneumococcal factors are involved in progression to invasive disease. We identify pneumococcal genes involved in invasiveness including pspC and zmpD, and perform a human-bacteria interaction analysis. These genes are potential candidates for the development of more broadly-acting pneumococcal vaccines.
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Affiliation(s)
- John A Lees
- Department of Microbiology, New York University School of Medicine, New York, NY, 10016, USA
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
| | - Bart Ferwerda
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
| | - Philip H C Kremer
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
| | - Nicole E Wheeler
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
- The Centre for Genomic Pathogen Surveillance, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
| | - Mercedes Valls Serón
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
| | - Nicholas J Croucher
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, W2 1PG, UK
| | | | - Hester J Bootsma
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, 3721 MA, The Netherlands
| | - Nynke Y Rots
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, 3721 MA, The Netherlands
| | - Alienke J Wijmega-Monsuur
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, 3721 MA, The Netherlands
| | - Elisabeth A M Sanders
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, 3721 MA, The Netherlands
- Department of Pediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, 3508 AB, The Netherlands
| | - Krzysztof Trzciński
- Department of Pediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, 3508 AB, The Netherlands
| | - Anne L Wyllie
- Department of Pediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, 3508 AB, The Netherlands
- Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, 06520, USA
| | - Aeilko H Zwinderman
- Amsterdam UMC, University of Amsterdam, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
| | - Leonard H van den Berg
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, 3584 CG, The Netherlands
| | - Wouter van Rheenen
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, 3584 CG, The Netherlands
| | - Jan H Veldink
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, 3584 CG, The Netherlands
| | - Zitta B Harboe
- Department of Microbiological Surveillance and Research, Statens Serum Institut, Copenhagen, DK-2300, Denmark
| | - Lene F Lundbo
- Department of Infectious Diseases, Hvidovre Hospital, University of Copenhagen, Hvidovre, 2650, Denmark
| | - Lisette C P G M de Groot
- Department of Human Nutrition, Wageningen University, P.O. Box 17, 6700 AA, Wageningen, The Netherlands
| | - Natasja M van Schoor
- Amsterdam UMC, VU University, Department of Epidemiology and Biostatistics, Amsterdam Public Health, Van der Boechorststraat 7, Amsterdam, 1007 MB, The Netherlands
| | - Nathalie van der Velde
- Amsterdam UMC, University of Amsterdam, Department of Internal Medicine, Geriatrics, Amsterdam Public Health, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Centre Rotterdam, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - Lars H Ängquist
- Center for Clinical Research and Disease Prevention, Bispebjerg and Frederiksberg Hospitals, The Capital Region, Copenhagen, DK-2000, Denmark
| | - Thorkild I A Sørensen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Copenhagen, DK-2200, Denmark
- The Department of Public Health, Section of Epidemiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, DK-1014, Denmark
| | - Ellen A Nohr
- Institute of Clinical Research, University of Southern Denmark, Odense, DK-5000, Denmark
| | - Alexander J Mentzer
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7BN, UK
| | - Tara C Mills
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7BN, UK
| | - Julian C Knight
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7BN, UK
| | - Mignon du Plessis
- School of Pathology, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, 2000, South Africa
| | - Susan Nzenze
- School of Pathology, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, 2000, South Africa
| | - Jeffrey N Weiser
- Department of Microbiology, New York University School of Medicine, New York, NY, 10016, USA
| | - Julian Parkhill
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
| | - Shabir Madhi
- National Institute for Communicable Diseases, Johannesburg, 2192, South Africa
| | - Thomas Benfield
- Department of Infectious Diseases, Hvidovre Hospital, University of Copenhagen, Hvidovre, 2650, Denmark
| | - Anne von Gottberg
- School of Pathology, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, 2000, South Africa
- National Institute for Communicable Diseases, Johannesburg, 2192, South Africa
| | - Arie van der Ende
- Amsterdam UMC, University of Amsterdam, Department of Medical Microbiology, Amsterdam Infection and Immunity, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
- Netherlands Reference Laboratory for Bacterial Meningitis, Amsterdam UMC/RIVM, University of Amsterdam, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
| | - Matthijs C Brouwer
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
| | - Jeffrey C Barrett
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
- Genomics Plc, East Road, Cambridge, CB1 1BH, UK
| | - Stephen D Bentley
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK.
| | - Diederik van de Beek
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands.
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12
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Puranen S, Pesonen M, Pensar J, Xu YY, Lees JA, Bentley SD, Croucher NJ, Corander J. SuperDCA for genome-wide epistasis analysis. Microb Genom 2018; 4. [PMID: 29813016 PMCID: PMC6096938 DOI: 10.1099/mgen.0.000184] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The potential for genome-wide modelling of epistasis has recently surfaced given the possibility of sequencing densely sampled populations and the emerging families of statistical interaction models. Direct coupling analysis (DCA) has previously been shown to yield valuable predictions for single protein structures, and has recently been extended to genome-wide analysis of bacteria, identifying novel interactions in the co-evolution between resistance, virulence and core genome elements. However, earlier computational DCA methods have not been scalable to enable model fitting simultaneously to 104-105 polymorphisms, representing the amount of core genomic variation observed in analyses of many bacterial species. Here, we introduce a novel inference method (SuperDCA) that employs a new scoring principle, efficient parallelization, optimization and filtering on phylogenetic information to achieve scalability for up to 105 polymorphisms. Using two large population samples of Streptococcus pneumoniae, we demonstrate the ability of SuperDCA to make additional significant biological findings about this major human pathogen. We also show that our method can uncover signals of selection that are not detectable by genome-wide association analysis, even though our analysis does not require phenotypic measurements. SuperDCA, thus, holds considerable potential in building understanding about numerous organisms at a systems biological level.
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Affiliation(s)
- Santeri Puranen
- 2Department of Mathematics and Statistics, Helsinki Institute of Information Technology (HIIT), FI-00014 University of Helsinki, Finland.,1Department of Computer Science, Aalto University, FI-00076 Espoo, Finland
| | - Maiju Pesonen
- 1Department of Computer Science, Aalto University, FI-00076 Espoo, Finland.,2Department of Mathematics and Statistics, Helsinki Institute of Information Technology (HIIT), FI-00014 University of Helsinki, Finland
| | - Johan Pensar
- 2Department of Mathematics and Statistics, Helsinki Institute of Information Technology (HIIT), FI-00014 University of Helsinki, Finland
| | - Ying Ying Xu
- 1Department of Computer Science, Aalto University, FI-00076 Espoo, Finland.,2Department of Mathematics and Statistics, Helsinki Institute of Information Technology (HIIT), FI-00014 University of Helsinki, Finland
| | - John A Lees
- 3Pathogen Genomics, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Stephen D Bentley
- 3Pathogen Genomics, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Nicholas J Croucher
- 4Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, UK
| | - Jukka Corander
- 5Department of Biostatistics, University of Oslo, 0317 Oslo, Norway.,2Department of Mathematics and Statistics, Helsinki Institute of Information Technology (HIIT), FI-00014 University of Helsinki, Finland.,3Pathogen Genomics, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
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13
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Martín-Galiano AJ, Ferrándiz MJ, de la Campa AG. Bridging Chromosomal Architecture and Pathophysiology of Streptococcus pneumoniae. Genome Biol Evol 2018; 9:350-361. [PMID: 28158485 PMCID: PMC5381641 DOI: 10.1093/gbe/evw299] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2016] [Indexed: 11/14/2022] Open
Abstract
The chromosome of Streptococcus pneumoniae is organized into topological domains based on its transcriptional response to DNA relaxation: Up-regulated (UP), down-regulated (DOWN), nonregulated (NR), and AT-rich. In the present work, NR genes found to have highly conserved chromosomal locations (17% of the genome) were categorized as members of position-conserved nonregulated (pcNR) domains, while NR genes with a variable position (36% of the genome) were classified as members of position-variable nonregulated (pvNR) domains. On average, pcNR domains showed high transcription rates, optimized codon usage, and were found to contain only a small number of RUP/BOX/SPLICE repeats. They were also poor in exogenous genes but enriched in leading strand genes that code for proteins involved in primary metabolism with central roles within the interactome. In contrast, pvNR genes coding for cell wall proteins, paralogs, virulence factors and immunogenic candidates for protein-based vaccines were found to be overrepresented. DOWN domains were enriched in genes essential for infection. Many UP and DOWN domain genes were seen to be activated during different stages of competence, whereas pcNR genes tended to be repressed until the competence was switched off. Pneumococcal genes appear to be subject to a topology-driven selection pressure that defines the chromosomal location of genes involved in metabolism, virulence and competence. The pcNR domains are interleaved between UP and DOWN domains according to a pattern that suggests the existence of macrodomain entities. The term “topogenomics” is here proposed to describe the study of the topological rules of genomes and their relationship with physiology.
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Affiliation(s)
- Antonio J Martín-Galiano
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Majadahonda, Spain
| | - María J Ferrándiz
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Majadahonda, Spain
| | - Adela G de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Majadahonda, Spain.,Unidad de Genética Bacteriana, Presidencia, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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14
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Corander J, Fraser C, Gutmann MU, Arnold B, Hanage WP, Bentley SD, Lipsitch M, Croucher NJ. Frequency-dependent selection in vaccine-associated pneumococcal population dynamics. Nat Ecol Evol 2017; 1:1950-1960. [PMID: 29038424 PMCID: PMC5708525 DOI: 10.1038/s41559-017-0337-x] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 09/01/2017] [Indexed: 12/21/2022]
Abstract
Many bacterial species are composed of multiple lineages distinguished by extensive variation in gene content. These often cocirculate in the same habitat, but the evolutionary and ecological processes that shape these complex populations are poorly understood. Addressing these questions is particularly important for Streptococcus pneumoniae, a nasopharyngeal commensal and respiratory pathogen, because the changes in population structure associated with the recent introduction of partial-coverage vaccines have substantially reduced pneumococcal disease. Here we show that pneumococcal lineages from multiple populations each have a distinct combination of intermediate-frequency genes. Functional analysis suggested that these loci may be subject to negative frequency-dependent selection (NFDS) through interactions with other bacteria, hosts or mobile elements. Correspondingly, these genes had similar frequencies in four populations with dissimilar lineage compositions. These frequencies were maintained following substantial alterations in lineage prevalences once vaccination programmes began. Fitting a multilocus NFDS model of post-vaccine population dynamics to three genomic datasets using Approximate Bayesian Computation generated reproducible estimates of the influence of NFDS on pneumococcal evolution, the strength of which varied between loci. Simulations replicated the stable frequency of lineages unperturbed by vaccination, patterns of serotype switching and clonal replacement. This framework highlights how bacterial ecology affects the impact of clinical interventions.
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Affiliation(s)
- Jukka Corander
- Helsinki Institute for Information Technology, Department of Mathematics and Statistics, University of Helsinki, 00014, Helsinki, Finland
- Department of Biostatistics, University of Oslo, 0317, Oslo, Norway
- Infection Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Christophe Fraser
- Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7LF, UK
| | - Michael U Gutmann
- School of Informatics, University of Edinburgh, Edinburgh, EH8 9AB, UK
| | - Brian Arnold
- Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
| | - William P Hanage
- Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
| | - Stephen D Bentley
- Infection Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Marc Lipsitch
- Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
- Departments of Epidemiology and Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
| | - Nicholas J Croucher
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, W2 1PG, UK.
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15
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de la Campa AG, Ferrándiz MJ, Martín-Galiano AJ, García MT, Tirado-Vélez JM. The Transcriptome of Streptococcus pneumoniae Induced by Local and Global Changes in Supercoiling. Front Microbiol 2017; 8:1447. [PMID: 28824578 PMCID: PMC5534458 DOI: 10.3389/fmicb.2017.01447] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/17/2017] [Indexed: 01/28/2023] Open
Abstract
The bacterial chromosome is compacted in a manner optimal for DNA transactions to occur. The degree of compaction results from the level of DNA-supercoiling and the presence of nucleoid-binding proteins. DNA-supercoiling is homeostatically maintained by the opposing activities of relaxing DNA topoisomerases and negative supercoil-inducing DNA gyrase. DNA-supercoiling acts as a general cis regulator of transcription, which can be superimposed upon other types of more specific trans regulatory mechanism. Transcriptomic studies on the human pathogen Streptococcus pneumoniae, which has a relatively small genome (∼2 Mb) and few nucleoid-binding proteins, have been performed under conditions of local and global changes in supercoiling. The response to local changes induced by fluoroquinolone antibiotics, which target DNA gyrase subunit A and/or topoisomerase IV, involves an increase in oxygen radicals which reduces cell viability, while the induction of global supercoiling changes by novobiocin (a DNA gyrase subunit B inhibitor), or by seconeolitsine (a topoisomerase I inhibitor), has revealed the existence of topological domains that specifically respond to such changes. The control of DNA-supercoiling in S. pneumoniae occurs mainly via the regulation of topoisomerase gene transcription: relaxation triggers the up-regulation of gyrase and the down-regulation of topoisomerases I and IV, while hypernegative supercoiling down-regulates the expression of topoisomerase I. Relaxation affects 13% of the genome, with the majority of the genes affected located in 15 domains. Hypernegative supercoiling affects 10% of the genome, with one quarter of the genes affected located in 12 domains. However, all the above domains overlap, suggesting that the chromosome is organized into topological domains with fixed locations. Based on its response to relaxation, the pneumococcal chromosome can be said to be organized into five types of domain: up-regulated, down-regulated, position-conserved non-regulated, position-variable non-regulated, and AT-rich. The AT content is higher in the up-regulated than in the down-regulated domains. Genes within the different domains share structural and functional characteristics. It would seem that a topology-driven selection pressure has defined the chromosomal location of the metabolism, virulence and competence genes, which suggests the existence of topological rules that aim to improve bacterial fitness.
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Affiliation(s)
- Adela G de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos IIIMadrid, Spain.,Presidencia, Consejo Superior de Investigaciones CientíficasMadrid, Spain
| | - María J Ferrándiz
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos IIIMadrid, Spain
| | - Antonio J Martín-Galiano
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos IIIMadrid, Spain
| | - María T García
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad ComplutenseMadrid, Spain
| | - Jose M Tirado-Vélez
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos IIIMadrid, Spain
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16
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Costa NS, Pinto TCA, Merquior VLC, Castro LFS, da Rocha FSP, Morais JM, Peralta JM, Teixeira LM. MLVA Typing of Streptococcus pneumoniae Isolates with Emphasis on Serotypes 14, 9N and 9V: Comparison of Previously Described Panels and Proposal of a Novel 7 VNTR Loci-Based Simplified Scheme. PLoS One 2016; 11:e0158651. [PMID: 27391462 PMCID: PMC4938579 DOI: 10.1371/journal.pone.0158651] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 06/20/2016] [Indexed: 11/18/2022] Open
Abstract
Streptococcus pneumoniae remains as an important cause of community-acquired bacterial infections, and the nasopharynx of asymptomatic carriers is the major reservoir of this microorganism. Pneumococcal strains of serotype 14 and serogroup 9 are among the most frequently isolated from both asymptomatic carriers and patients with invasive disease living in Brazil. Internationally disseminated clones belonging to such serotypes have been associated with the emergence and spread of antimicrobial resistance in our setting, highlighting the need for epidemiological tracking of these isolates. In this scenario, Multiple Loci VNTR Analysis (MLVA) has emerged as an alternative tool for the molecular characterization of pneumococci, in addition to more traditional techniques such as Multi-Locus Sequence Typing (MLST) and Pulsed-Field Gel Electrophoresis (PFGE). In the present study, 18 VNTR loci, as well as other previously described reduced MLVA panels (7 VNTR loci), were evaluated as tools to characterize pneumococcal strains of serotypes 14, 9N and 9V belonging to international and regional clones isolated in Brazil. The 18 VNTR loci panel was highly congruent with MLST and PFGE, being also useful for indicating the genetic relationship with international clones and for discriminating among strains with indistinguishable STs and PFGE profiles. Analysis of the results also allowed deducing a novel shorter 7 VNTR loci panel, keeping a high discriminatory power for isolates of the serotypes investigated and a high congruence level with MLST and PFGE. The newly proposed simplified panel was then evaluated for typing pneumococcal strains of other commonly isolated serotypes. The results indicate that MLVA is a faster and easier to perform, reliable approach for the molecular characterization of S. pneumoniae isolates, with potential for cost-effective application, especially in resource-limited countries.
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Affiliation(s)
- Natália S. Costa
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
- Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Tatiana C. A. Pinto
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Vânia L. C. Merquior
- Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Luciana F. S. Castro
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Filomena S. P. da Rocha
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Jaqueline M. Morais
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - José M. Peralta
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Lúcia M. Teixeira
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
- * E-mail:
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17
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Complete Genome Sequence of Streptococcus mitis Strain SVGS_061 Isolated from a Neutropenic Patient with Viridans Group Streptococcal Shock Syndrome. GENOME ANNOUNCEMENTS 2016; 4:4/2/e00259-16. [PMID: 27056234 PMCID: PMC4824267 DOI: 10.1128/genomea.00259-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Streptococcus mitisfrequently causes invasive infections in neutropenic cancer patients, with a subset of patients developing viridans group streptococcal (VGS) shock syndrome. We report here the first complete genome sequence ofS. mitisstrain SVGS_061, which caused VGS shock syndrome, to help elucidate the pathogenesis of severe VGS infection.
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18
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Population genomic datasets describing the post-vaccine evolutionary epidemiology of Streptococcus pneumoniae. Sci Data 2015; 2:150058. [PMID: 26528397 PMCID: PMC4622223 DOI: 10.1038/sdata.2015.58] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/28/2015] [Indexed: 11/08/2022] Open
Abstract
Streptococcus pneumoniae is common nasopharyngeal commensal bacterium and important human pathogen. Vaccines against a subset of pneumococcal antigenic diversity have reduced rates of disease, without changing the frequency of asymptomatic carriage, through altering the bacterial population structure. These changes can be studied in detail through using genome sequencing to characterise systematically-sampled collections of carried S. pneumoniae. This dataset consists of 616 annotated draft genomes of isolates collected from children during routine visits to primary care physicians in Massachusetts between 2001, shortly after the seven valent polysaccharide conjugate vaccine was introduced, and 2007. Also made available are a core genome alignment and phylogeny describing the overall population structure, clusters of orthologous protein sequences, software for inferring serotype from Illumina reads, and whole genome alignments for the analysis of closely-related sets of pneumococci. These data can be used to study both bacterial evolution and the epidemiology of a pathogen population under selection from vaccine-induced immunity.
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19
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Holder IT, Wagner S, Xiong P, Sinn M, Frickey T, Meyer A, Hartig JS. Intrastrand triplex DNA repeats in bacteria: a source of genomic instability. Nucleic Acids Res 2015; 43:10126-42. [PMID: 26450966 PMCID: PMC4666352 DOI: 10.1093/nar/gkv1017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 09/21/2015] [Indexed: 01/10/2023] Open
Abstract
Repetitive nucleic acid sequences are often prone to form secondary structures distinct from B-DNA. Prominent examples of such structures are DNA triplexes. We observed that certain intrastrand triplex motifs are highly conserved and abundant in prokaryotic genomes. A systematic search of 5246 different prokaryotic plasmids and genomes for intrastrand triplex motifs was conducted and the results summarized in the ITxF database available online at http://bioinformatics.uni-konstanz.de/utils/ITxF/. Next we investigated biophysical and biochemical properties of a particular G/C-rich triplex motif (TM) that occurs in many copies in more than 260 bacterial genomes by CD and nuclear magnetic resonance spectroscopy as well as in vivo footprinting techniques. A characterization of putative properties and functions of these unusually frequent nucleic acid motifs demonstrated that the occurrence of the TM is associated with a high degree of genomic instability. TM-containing genomic loci are significantly more rearranged among closely related Escherichia coli strains compared to control sites. In addition, we found very high frequencies of TM motifs in certain Enterobacteria and Cyanobacteria that were previously described as genetically highly diverse. In conclusion we link intrastrand triplex motifs with the induction of genomic instability. We speculate that the observed instability might be an adaptive feature of these genomes that creates variation for natural selection to act upon.
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Affiliation(s)
- Isabelle T Holder
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Stefanie Wagner
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Peiwen Xiong
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Malte Sinn
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Tancred Frickey
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Axel Meyer
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Jörg S Hartig
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
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Morales M, Martín-Galiano AJ, Domenech M, García E. Insights into the Evolutionary Relationships of LytA Autolysin and Ply Pneumolysin-Like Genes in Streptococcus pneumoniae and Related Streptococci. Genome Biol Evol 2015; 7:2747-61. [PMID: 26349755 PMCID: PMC4607534 DOI: 10.1093/gbe/evv178] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Streptococcus pneumoniae (pneumococcus) is a major human pathogen. The main pneumococcal autolysin LytA and the pneumolysin Ply are two of the bacterium's most important virulence factors. The lytA- and ply-related genes are also found in other streptococci of the Mitis group (SMG). The precise characteristics of the lytA-related-but not the ply-related-genes of SMG and their prophages have been previously described. A search of the more than 400 SMG genomic sequences available in public databases (ca. 300 for S. pneumoniae), showed Streptococcus pseudopneumoniae IS7493 to harbor four ply-related genes, two of which (plyA and plyB) have 98% identical nucleotides. The plyA homolog of S. pseudopneumoniae is conserved in all S. pneumoniae strains, and seems to be included in a pathogenicity island together with the lytA gene. However, only nonencapsulated S. pneumoniae strains possess a plyB gene, which is part of an integrative and conjugative element. Notably, the existence of a bacterial lytA-related gene in a genome is linked to the presence of plyA and vice versa. The present analysis also shows there are eight main types of plyA-lytA genomic islands. A possible stepwise scenario for the evolution of the plyA-lytA island in S. pneumoniae is proposed.
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Affiliation(s)
- María Morales
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain Unidad de Genética Bacteriana, Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Antonio J Martín-Galiano
- Unidad de Genética Bacteriana, Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Madrid, Spain Centro Nacional de Microbiología, ISCIII, Majadahonda, Madrid, Spain
| | - Mirian Domenech
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain Unidad de Genética Bacteriana, Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Ernesto García
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain Unidad de Genética Bacteriana, Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
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Modified MLVA for Genotyping Queensland Invasive Streptococcus pneumoniae. PLoS One 2015; 10:e0121870. [PMID: 25923909 PMCID: PMC4414480 DOI: 10.1371/journal.pone.0121870] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 02/20/2015] [Indexed: 11/25/2022] Open
Abstract
Background Globally, over 800 000 children under five die each year from infectious diseases caused by Streptococcus pneumoniae. To understand genetic relatedness between isolates, study transmission routes, assess the impact of human interventions e.g. vaccines, and determine infection sources, genotyping methods are required. The ‘gold standard’ genotyping method, Multi-Locus Sequence Typing (MLST), is useful for long-term and global studies. Another genotyping method, Multi-Locus Variable Number of Tandem Repeat Analysis (MLVA), has emerged as a more discriminatory, inexpensive and faster technique; however there is no universally accepted method and it is currently suitable for short-term and localised epidemiology studies. Currently Australia has no national MLST database, nor has it adopted any MLVA method for short-term or localised studies. This study aims to improve S. pneumoniae genotyping methods by modifying the existing MLVA techniques to be more discriminatory, faster, cheaper and technically less demanding than previously published MLVA methods and MLST. Methods Four different MLVA protocols, including a modified method, were applied to 317 isolates of serotyped invasive S. pneumoniae isolated from sterile body sites of Queensland children under 15 years from 2007–2012. MLST was applied to 202 isolates for comparison. Results The modified MLVA4 is significantly more discriminatory than the ‘gold standard’ MLST method. MLVA4 has similar discrimination compared to other MLVA techniques in this study). The failure to amplify particular loci in previous MLVA methods were minimised in MLVA4. Failure to amplify BOX-13 and Spneu19 were found to be serotype specific. Conclusion We have modified a highly discriminatory MLVA technique for genotyping Queensland invasive S. pneumoniae. MLVA4 has the ability to enhance our understanding of the pneumococcal epidemiology and the changing genetics of the pneumococcus in localised and short-term studies.
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Wilton J, Acebo P, Herranz C, Gómez A, Amblar M. Small regulatory RNAs in Streptococcus pneumoniae: discovery and biological functions. Front Genet 2015; 6:126. [PMID: 25904932 PMCID: PMC4387999 DOI: 10.3389/fgene.2015.00126] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 03/17/2015] [Indexed: 12/23/2022] Open
Abstract
Streptococcus pneumoniae is a prominent human pathogen responsible for many severe diseases and the leading cause of childhood mortality worldwide. The pneumococcus is remarkably adept at colonizing and infecting different niches in the human body, and its adaptation to dynamic host environment is a central aspect of its pathogenesis. In the last decade, increasing findings have evidenced small RNAs (sRNAs) as vital regulators in a number of important processes in bacteria. In S. pneumoniae, a small antisense RNA was first discovered in the pMV158 plasmid as a copy number regulator. More recently, genome-wide screens revealed that the pneumococcal genome also encodes multiple sRNAs, many of which have important roles in virulence while some are implicated in competence control. The knowledge of the sRNA-mediated regulation in pneumococcus remains very limited, and future research is needed for better understanding of functions and mechanisms. Here, we provide a comprehensive summary of the current knowledge on sRNAs from S. pneumoniae, focusing mainly on the trans-encoded sRNAs.
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Affiliation(s)
- Joana Wilton
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Paloma Acebo
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Cristina Herranz
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Alicia Gómez
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Mónica Amblar
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain ; CIBER Enfermedades Respiratorias Madrid, Spain
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Rayner RE, Savill J, Hafner LM, Huygens F. Genotyping Streptococcus pneumoniae. Future Microbiol 2015; 10:653-64. [DOI: 10.2217/fmb.14.153] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
ABSTRACT Streptococcus pneumoniae is a potentially deadly human pathogen associated with high morbidity, mortality and global economic burden. The universally used bacterial genotyping methods are multilocus sequence typing and pulsed field gel electrophoresis. However, another highly discriminatory, rapid and less expensive genotyping technique, multilocus variable number of tandem repeat analysis (MLVA), has been developed. Unfortunately, no universal MLVA protocol exists, and some MLVA protocols do not amplify certain loci for all pneumococcal serotypes, leaving genotyping profiles incomplete. A number of other genotyping or characterization methods have been developed and will be discussed. This review examines the various protocols for genotyping S. pneumoniae and highlights the current direction technology and research is heading to understand this bacterium.
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Affiliation(s)
- Rachael E Rayner
- Institute of Health & Biomedical Innovation (IHBI), 60 Musk Ave, Kelvin Grove, 4059, Queensland, Australia
| | - John Savill
- Public Health Microbiology Laboratory, Queensland Health Forensic & Scientific Services, Coopers Plains, Queensland, Australia
| | - Louise M Hafner
- Queensland University of Technology (QUT), Brisbane, Queensland, Australia
| | - Flavia Huygens
- Institute of Health & Biomedical Innovation (IHBI), 60 Musk Ave, Kelvin Grove, 4059, Queensland, Australia
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Sequence elements upstream of the core promoter are necessary for full transcription of the capsule gene operon in Streptococcus pneumoniae strain D39. Infect Immun 2015; 83:1957-72. [PMID: 25733517 DOI: 10.1128/iai.02944-14] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 02/16/2015] [Indexed: 02/05/2023] Open
Abstract
Streptococcus pneumoniae is a major bacterial pathogen in humans. Its polysaccharide capsule is a key virulence factor that promotes bacterial evasion of human phagocytic killing. While S. pneumoniae produces at least 94 antigenically different types of capsule, the genes for biosynthesis of almost all capsular types are arranged in the same locus. The transcription of the capsular polysaccharide (cps) locus is not well understood. This study determined the transcriptional features of the cps locus in the type 2 virulent strain D39. The initial analysis revealed that the cps genes are cotranscribed from a major transcription start site at the -25 nucleotide (G) upstream of cps2A, the first gene in the locus. Using unmarked chromosomal truncations and a luciferase-based transcriptional reporter, we showed that the full transcription of the cps genes not only depends on the core promoter immediately upstream of cps2A, but also requires additional elements upstream of the core promoter, particularly a 59-bp sequence immediately upstream of the core promoter. Unmarked deletions of these promoter elements in the D39 genome also led to significant reduction in CPS production and virulence in mice. Lastly, common cps gene (cps2ABCD) mutants did not show significant abnormality in cps transcription, although they produced significantly less CPS, indicating that the CpsABCD proteins are involved in the encapsulation of S. pneumoniae in a posttranscriptional manner. This study has yielded important information on the transcriptional characteristics of the cps locus in S. pneumoniae.
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Brettin T, Davis JJ, Disz T, Edwards RA, Gerdes S, Olsen GJ, Olson R, Overbeek R, Parrello B, Pusch GD, Shukla M, Thomason JA, Stevens R, Vonstein V, Wattam AR, Xia F. RASTtk: a modular and extensible implementation of the RAST algorithm for building custom annotation pipelines and annotating batches of genomes. Sci Rep 2015; 5:8365. [PMID: 25666585 PMCID: PMC4322359 DOI: 10.1038/srep08365] [Citation(s) in RCA: 1721] [Impact Index Per Article: 191.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/02/2015] [Indexed: 12/31/2022] Open
Abstract
The RAST (Rapid Annotation using Subsystem Technology) annotation engine was built in 2008 to annotate bacterial and archaeal genomes. It works by offering a standard software pipeline for identifying genomic features (i.e., protein-encoding genes and RNA) and annotating their functions. Recently, in order to make RAST a more useful research tool and to keep pace with advancements in bioinformatics, it has become desirable to build a version of RAST that is both customizable and extensible. In this paper, we describe the RAST tool kit (RASTtk), a modular version of RAST that enables researchers to build custom annotation pipelines. RASTtk offers a choice of software for identifying and annotating genomic features as well as the ability to add custom features to an annotation job. RASTtk also accommodates the batch submission of genomes and the ability to customize annotation protocols for batch submissions. This is the first major software restructuring of RAST since its inception.
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Affiliation(s)
- Thomas Brettin
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Computation Institute, University of Chicago, Chicago, Illinois, 60637, USA
| | - James J. Davis
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Computation Institute, University of Chicago, Chicago, Illinois, 60637, USA
| | - Terry Disz
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, 60527, USA
| | - Robert A. Edwards
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
- Department of Computer Science, San Diego State University, San Diego, California, 92182, USA
| | - Svetlana Gerdes
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, 60527, USA
| | - Gary J. Olsen
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Robert Olson
- Computation Institute, University of Chicago, Chicago, Illinois, 60637, USA
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Ross Overbeek
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, 60527, USA
| | - Bruce Parrello
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, 60527, USA
| | - Gordon D. Pusch
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, 60527, USA
| | - Maulik Shukla
- Virginia Bioinformatics Institute, Virginia Tech University, Blacksburg, VA, 24060, USA
| | - James A. Thomason
- USDA-ARS Laboratory at Cold Spring Harbor Laboratory, Cold Spring Harbor NY, 11724, USA
| | - Rick Stevens
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Computation Institute, University of Chicago, Chicago, Illinois, 60637, USA
- Department of Computer Science, University of Chicago, Chicago, Illinois, 60637, USA
| | - Veronika Vonstein
- Computing, Environment and Life Sciences, Argonne National Laboratory, Argonne IL, 60439, USA
- Fellowship for Interpretation of Genomes, Burr Ridge, IL, 60527, USA
| | - Alice R. Wattam
- Virginia Bioinformatics Institute, Virginia Tech University, Blacksburg, VA, 24060, USA
| | - Fangfang Xia
- Computation Institute, University of Chicago, Chicago, Illinois, 60637, USA
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
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Croucher NJ, Coupland PG, Stevenson AE, Callendrello A, Bentley SD, Hanage WP. Diversification of bacterial genome content through distinct mechanisms over different timescales. Nat Commun 2014; 5:5471. [PMID: 25407023 PMCID: PMC4263131 DOI: 10.1038/ncomms6471] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/03/2014] [Indexed: 12/16/2022] Open
Abstract
Bacterial populations often consist of multiple co-circulating lineages. Determining how such population structures arise requires understanding what drives bacterial diversification. Using 616 systematically sampled genomes, we show that Streptococcus pneumoniae lineages are typically characterized by combinations of infrequently transferred stable genomic islands: those moving primarily through transformation, along with integrative and conjugative elements and phage-related chromosomal islands. The only lineage containing extensive unique sequence corresponds to a set of atypical unencapsulated isolates that may represent a distinct species. However, prophage content is highly variable even within lineages, suggesting frequent horizontal transmission that would necessitate rapidly diversifying anti-phage mechanisms to prevent these viruses sweeping through populations. Correspondingly, two loci encoding Type I restriction-modification systems able to change their specificity over short timescales through intragenomic recombination are ubiquitous across the collection. Hence short-term pneumococcal variation is characterized by movement of phage and intragenomic rearrangements, with the slower transfer of stable loci distinguishing lineages. Populations of the pathogenic bacterium Streptococcus pneumoniae consist of distinct co-circulating lineages. Here, the authors show lineages are characterized by particular combinations of stable genomic islands, whereas prophage and restriction-modification systems vary over short timescales.
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Affiliation(s)
- Nicholas J Croucher
- 1] Centre for Communicable Disease Dynamics, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, USA [2] Department of Infectious Disease Epidemiology, St. Mary's Campus, Imperial College, London W2 1PG, UK
| | - Paul G Coupland
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Abbie E Stevenson
- Centre for Communicable Disease Dynamics, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, USA
| | - Alanna Callendrello
- Centre for Communicable Disease Dynamics, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, USA
| | - Stephen D Bentley
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - William P Hanage
- Centre for Communicable Disease Dynamics, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, USA
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Vergara-Irigaray M, Fookes MC, Thomson NR, Tang CM. RNA-seq analysis of the influence of anaerobiosis and FNR on Shigella flexneri. BMC Genomics 2014; 15:438. [PMID: 24907032 PMCID: PMC4229854 DOI: 10.1186/1471-2164-15-438] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 05/23/2014] [Indexed: 01/03/2023] Open
Abstract
Background Shigella flexneri is an important human pathogen that has to adapt to the anaerobic environment in the gastrointestinal tract to cause dysentery. To define the influence of anaerobiosis on the virulence of Shigella, we performed deep RNA sequencing to identify transcriptomic differences that are induced by anaerobiosis and modulated by the anaerobic Fumarate and Nitrate Reduction regulator, FNR. Results We found that 528 chromosomal genes were differentially expressed in response to anaerobic conditions; of these, 228 genes were also influenced by FNR. Genes that were up-regulated in anaerobic conditions are involved in carbon transport and metabolism (e.g. ptsG, manX, murQ, cysP, cra), DNA topology and regulation (e.g. ygiP, stpA, hns), host interactions (e.g. yciD, nmpC, slyB, gapA, shf, msbB) and survival within the gastrointestinal tract (e.g. shiA, ospI, adiY, cysP). Interestingly, there was a marked effect of available oxygen on genes involved in Type III secretion system (T3SS), which is required for host cell invasion and pathogenesis. These genes, located on the large Shigella virulence plasmid, were down regulated in anaerobiosis in an FNR-dependent manner. We also confirmed anaerobic induction of csrB and csrC small RNAs in an FNR-independent manner. Conclusions Anaerobiosis promotes survival and adaption strategies of Shigella, while modulating virulence plasmid genes involved in T3SS-mediated host cell invasion. The influence of FNR on this process is more extensive than previously appreciated, although aside from the virulence plasmid, this transcriptional regulator does not govern expression of genes on other horizontally acquired sequences on the chromosome such as pathogenicity islands. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-438) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | - Christoph M Tang
- Sir William Dunn School of Pathology, Oxford University, Oxford, United Kingdom.
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Abstract
Bacterial genomes are remarkably stable from one generation to the next but are plastic on an evolutionary time scale, substantially shaped by horizontal gene transfer, genome rearrangement, and the activities of mobile DNA elements. This implies the existence of a delicate balance between the maintenance of genome stability and the tolerance of genome instability. In this review, we describe the specialized genetic elements and the endogenous processes that contribute to genome instability. We then discuss the consequences of genome instability at the physiological level, where cells have harnessed instability to mediate phase and antigenic variation, and at the evolutionary level, where horizontal gene transfer has played an important role. Indeed, this ability to share DNA sequences has played a major part in the evolution of life on Earth. The evolutionary plasticity of bacterial genomes, coupled with the vast numbers of bacteria on the planet, substantially limits our ability to control disease.
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Van den Bogert B, Boekhorst J, Herrmann R, Smid EJ, Zoetendal EG, Kleerebezem M. Comparative genomics analysis of Streptococcus isolates from the human small intestine reveals their adaptation to a highly dynamic ecosystem. PLoS One 2013; 8:e83418. [PMID: 24386196 PMCID: PMC3875467 DOI: 10.1371/journal.pone.0083418] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 11/04/2013] [Indexed: 02/07/2023] Open
Abstract
The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core genome. Genome mining of the small-intestinal streptococci focused on functions playing an important role in the interaction of these streptococci in the small-intestinal ecosystem, including natural competence and nutrient-transport and metabolism. Analysis of the small-intestinal Streptococcus genomes predicts a high capacity to synthesize amino acids and various vitamins as well as substantial divergence in their carbohydrate transport and metabolic capacities, which is in agreement with observed physiological differences between these Streptococcus strains. Gene-specific PCR-strategies enabled evaluation of conservation of Streptococcus populations in intestinal samples from different human individuals, revealing that the S. salivarius strains were frequently detected in the small-intestine microbiota, supporting the representative value of the genomes provided in this study. Finally, the Streptococcus genomes allow prediction of the effect of dietary substances on Streptococcus population dynamics in the human small-intestine.
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Affiliation(s)
- Bartholomeus Van den Bogert
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Jos Boekhorst
- Centre for Molecular and Biomolecular Informatics, Radboud University Medical Centre, Nijmegen, The Netherlands
- NIZO Food Research B.V., Ede, The Netherlands
| | - Ruth Herrmann
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Eddy J. Smid
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Laboratory of Food Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Erwin G. Zoetendal
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Michiel Kleerebezem
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
- NIZO Food Research B.V., Ede, The Netherlands
- Host-Microbe Interactomics Group, Wageningen University, Wageningen, The Netherlands
- * E-mail:
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Olson AB, Kent H, Sibley CD, Grinwis ME, Mabon P, Ouellette C, Tyson S, Graham M, Tyler SD, Van Domselaar G, Surette MG, Corbett CR. Phylogenetic relationship and virulence inference of Streptococcus Anginosus Group: curated annotation and whole-genome comparative analysis support distinct species designation. BMC Genomics 2013; 14:895. [PMID: 24341328 PMCID: PMC3897883 DOI: 10.1186/1471-2164-14-895] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 12/09/2013] [Indexed: 12/30/2022] Open
Abstract
Background The Streptococcus Anginosus Group (SAG) represents three closely related species of the viridans group streptococci recognized as commensal bacteria of the oral, gastrointestinal and urogenital tracts. The SAG also cause severe invasive infections, and are pathogens during cystic fibrosis (CF) pulmonary exacerbation. Little genomic information or description of virulence mechanisms is currently available for SAG. We conducted intra and inter species whole-genome comparative analyses with 59 publically available Streptococcus genomes and seven in-house closed high quality finished SAG genomes; S. constellatus (3), S. intermedius (2), and S. anginosus (2). For each SAG species, we sequenced at least one numerically dominant strain from CF airways recovered during acute exacerbation and an invasive, non-lung isolate. We also evaluated microevolution that occurred within two isolates that were cultured from one individual one year apart. Results The SAG genomes were most closely related to S. gordonii and S. sanguinis, based on shared orthologs and harbor a similar number of proteins within each COG category as other Streptococcus species. Numerous characterized streptococcus virulence factor homologs were identified within the SAG genomes including; adherence, invasion, spreading factors, LPxTG cell wall proteins, and two component histidine kinases known to be involved in virulence gene regulation. Mobile elements, primarily integrative conjugative elements and bacteriophage, account for greater than 10% of the SAG genomes. S. anginosus was the most variable species sequenced in this study, yielding both the smallest and the largest SAG genomes containing multiple genomic rearrangements, insertions and deletions. In contrast, within the S. constellatus and S. intermedius species, there was extensive continuous synteny, with only slight differences in genome size between strains. Within S. constellatus we were able to determine important SNPs and changes in VNTR numbers that occurred over the course of one year. Conclusions The comparative genomic analysis of the SAG clarifies the phylogenetics of these bacteria and supports the distinct species classification. Numerous potential virulence determinants were identified and provide a foundation for further studies into SAG pathogenesis. Furthermore, the data may be used to enable the development of rapid diagnostic assays and therapeutics for these pathogens.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Michael G Surette
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
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Toxin-antitoxin genes of the Gram-positive pathogen Streptococcus pneumoniae: so few and yet so many. Microbiol Mol Biol Rev 2013. [PMID: 23204366 DOI: 10.1128/mmbr.00030-12] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Pneumococcal infections cause up to 2 million deaths annually and raise a large economic burden and thus constitute an important threat to mankind. Because of the increase in the antibiotic resistance of Streptococcus pneumoniae clinical isolates, there is an urgent need to find new antimicrobial approaches to triumph over pneumococcal infections. Toxin-antitoxin (TA) systems (TAS), which are present in most living bacteria but not in eukaryotes, have been proposed as an effective strategy to combat bacterial infections. Type II TAS comprise a stable toxin and a labile antitoxin that form an innocuous TA complex under normal conditions. Under stress conditions, TA synthesis will be triggered, resulting in the degradation of the labile antitoxin and the release of the toxin protein, which would poison the host cells. The three functional chromosomal TAS from S. pneumoniae that have been studied as well as their molecular characteristics are discussed in detail in this review. Furthermore, a meticulous bioinformatics search has been performed for 48 pneumococcal genomes that are found in public databases, and more putative TAS, homologous to well-characterized ones, have been revealed. Strikingly, several unusual putative TAS, in terms of components and genetic organizations previously not envisaged, have been discovered and are further discussed. Previously, we reported a novel finding in which a unique pneumococcal DNA signature, the BOX element, affected the regulation of the pneumococcal yefM-yoeB TAS. This BOX element has also been found in some of the other pneumococcal TAS. In this review, we also discuss possible relationships between some of the pneumococcal TAS with pathogenicity, competence, biofilm formation, persistence, and an interesting phenomenon called bistability.
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Croucher NJ, Mitchell AM, Gould KA, Inverarity D, Barquist L, Feltwell T, Fookes MC, Harris SR, Dordel J, Salter SJ, Browall S, Zemlickova H, Parkhill J, Normark S, Henriques-Normark B, Hinds J, Mitchell TJ, Bentley SD. Dominant role of nucleotide substitution in the diversification of serotype 3 pneumococci over decades and during a single infection. PLoS Genet 2013; 9:e1003868. [PMID: 24130509 PMCID: PMC3794909 DOI: 10.1371/journal.pgen.1003868] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 08/24/2013] [Indexed: 01/12/2023] Open
Abstract
Streptococcus pneumoniae of serotype 3 possess a mucoid capsule and cause disease associated with high mortality rates relative to other pneumococci. Phylogenetic analysis of a complete reference genome and 81 draft sequences from clonal complex 180, the predominant serotype 3 clone in much of the world, found most sampled isolates belonged to a clade affected by few diversifying recombinations. However, other isolates indicate significant genetic variation has accumulated over the clonal complex's entire history. Two closely related genomes, one from the blood and another from the cerebrospinal fluid, were obtained from a patient with meningitis. The pair differed in their behaviour in a mouse model of disease and in their susceptibility to antimicrobials, with at least some of these changes attributable to a mutation that up-regulated the patAB efflux pump. This indicates clinically important phenotypic variation can accumulate rapidly through small alterations to the genotype.
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Affiliation(s)
- Nicholas J. Croucher
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
- * E-mail: (NJC); (TJM)
| | - Andrea M. Mitchell
- Institute of Microbiology and Infection and School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Katherine A. Gould
- Bacterial Microarray Group, Division of Clinical Sciences, St. George's Hospital, University of London, London, United Kingdom
| | - Donald Inverarity
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Lars Barquist
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Theresa Feltwell
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Maria C. Fookes
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Simon R. Harris
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Janina Dordel
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Susannah J. Salter
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Sarah Browall
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Dept. of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | | | - Julian Parkhill
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Staffan Normark
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Dept. of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Birgitta Henriques-Normark
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Dept. of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Jason Hinds
- Bacterial Microarray Group, Division of Clinical Sciences, St. George's Hospital, University of London, London, United Kingdom
| | - Tim J. Mitchell
- Institute of Microbiology and Infection and School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- * E-mail: (NJC); (TJM)
| | - Stephen D. Bentley
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom
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Shahinas D, Thornton CS, Tamber GS, Arya G, Wong A, Jamieson FB, Ma JH, Alexander DC, Low DE, Pillai DR. Comparative Genomic Analyses of Streptococcus pseudopneumoniae Provide Insight into Virulence and Commensalism Dynamics. PLoS One 2013; 8:e65670. [PMID: 23840352 PMCID: PMC3686770 DOI: 10.1371/journal.pone.0065670] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/26/2013] [Indexed: 01/31/2023] Open
Abstract
Streptococcus pseudopneumoniae (SPPN) is a recently described species of the viridans group streptococci (VGS). Although the pathogenic potential of S. pseudopneumoniae remains uncertain, it is most commonly isolated from patients with underlying medical conditions, such as chronic obstructive pulmonary disease. S. pseudopneumoniae can be distinguished from the closely related species, S. pneumoniae and S. mitis, by phenotypic characteristics, including optochin resistance in the presence of 5% CO2, bile insolubility, and the lack of the pneumococcal capsule. Previously, we reported the draft genome sequence of S. pseudopneumoniae IS7493, a clinical isolate obtained from an immunocompromised patient with documented pneumonia. Here, we use comparative genomics approaches to identify similarities and key differences between S. pseudopneumoniae IS7493, S. pneumoniae and S. mitis. The genome structure of S. pseudopneumoniae IS7493 is most closely related to that of S. pneumoniae R6, but several recombination events are evident. Analysis of gene content reveals numerous unique features that distinguish S. pseudopneumoniae from other streptococci. The presence of loci for competence, iron transport, pneumolysin production and antimicrobial resistance reinforce the phylogenetic position of S. pseudopneumoniae as an intermediate species between S. pneumoniae and S. mitis. Additionally, the presence of several virulence factors and antibiotic resistance mechanisms suggest the potential of this commensal species to become pathogenic or to contribute to increasing antibiotic resistance levels seen among the VGS.
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Affiliation(s)
- Dea Shahinas
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
- * E-mail:
| | - Christina S. Thornton
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Canada
| | | | | | | | - Frances B. Jamieson
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
- Public Health Ontario, Toronto, Canada
| | - Jennifer H. Ma
- Public Health Ontario, Toronto, Canada
- DNA Core Facility, Public Health Ontario, Toronto, Canada
| | - David C. Alexander
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
- Public Health Ontario, Toronto, Canada
- DNA Core Facility, Public Health Ontario, Toronto, Canada
| | - Donald E. Low
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Dylan R. Pillai
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Canada
- Pathology and Laboratory Medicine, University of Calgary, Calgary, Canada
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34
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Donkor ES. Understanding the pneumococcus: transmission and evolution. Front Cell Infect Microbiol 2013; 3:7. [PMID: 23471303 PMCID: PMC3590460 DOI: 10.3389/fcimb.2013.00007] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 02/12/2013] [Indexed: 11/24/2022] Open
Abstract
Streptococcus pneumoniae is part of the normal bacterial flora of the narsopharynx, but is also associated with several invasive and non-invasive diseases. Recently, there has been a plethora of research information on the pneumococcus, however, there are few comprehensive review papers discussing the research information. This paper provides a review of the pneumococcus in two vital areas related to its biology including transmission and evolution. Transmission of the pneumococcus is a highly efficient process that usually occurs through respiratory droplets from asymptomatic carriers. Following acquisition, the pneumococcus may only establish in the nasopharynx of the new host, or further progress to sites such as the lungs and cause disease. Pneumococcus transmission risk factors, as well as factors involved in its translocation from the nasophyarnx to diseases sites are still not fully understood. Pneumococcal evolution is dominated by recombination. The recombinational events usually involve genetic exchange with streptococci of the mitis group and some pneumococci are thought to exhibit hyper-recombination.
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Affiliation(s)
- Eric S Donkor
- Department of Microbiology, University of Ghana Medical School Accra, Ghana. ;
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Bryant J, Chewapreecha C, Bentley SD. Developing insights into the mechanisms of evolution of bacterial pathogens from whole-genome sequences. Future Microbiol 2012; 7:1283-1296. [PMID: 23075447 PMCID: PMC3996552 DOI: 10.2217/fmb.12.108] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Evolution of bacterial pathogen populations has been detected in a variety of ways including phenotypic tests, such as metabolic activity, reaction to antisera and drug resistance and genotypic tests that measure variation in chromosome structure, repetitive loci and individual gene sequences. While informative, these methods only capture a small subset of the total variation and, therefore, have limited resolution. Advances in sequencing technologies have made it feasible to capture whole-genome sequence variation for each sample under study, providing the potential to detect all changes at all positions in the genome from single nucleotide changes to large-scale insertions and deletions. In this review, we focus on recent work that has applied this powerful new approach and summarize some of the advances that this has brought in our understanding of the details of how bacterial pathogens evolve.
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Affiliation(s)
- Josephine Bryant
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SA, UK
| | - Claire Chewapreecha
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SA, UK
| | - Stephen D Bentley
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SA, UK
- Department of Medicine, University of Cambridge, Addenbrooke’s Hospital, Cambridge, CB2 0QQ, UK
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Mann B, van Opijnen T, Wang J, Obert C, Wang YD, Carter R, McGoldrick DJ, Ridout G, Camilli A, Tuomanen EI, Rosch JW. Control of virulence by small RNAs in Streptococcus pneumoniae. PLoS Pathog 2012; 8:e1002788. [PMID: 22807675 PMCID: PMC3395615 DOI: 10.1371/journal.ppat.1002788] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 05/22/2012] [Indexed: 01/10/2023] Open
Abstract
Small noncoding RNAs (sRNAs) play important roles in gene regulation in both prokaryotes and eukaryotes. Thus far, no sRNA has been assigned a definitive role in virulence in the major human pathogen Streptococcus pneumoniae. Based on the potential coding capacity of intergenic regions, we hypothesized that the pneumococcus produces many sRNAs and that they would play an important role in pathogenesis. We describe the application of whole-genome transcriptional sequencing to systematically identify the sRNAs of Streptococcus pneumoniae. Using this approach, we have identified 89 putative sRNAs, 56 of which are newly identified. Furthermore, using targeted genetic approaches and Tn-seq transposon screening, we demonstrate that many of the identified sRNAs have important global and niche-specific roles in virulence. These data constitute the most comprehensive analysis of pneumococcal sRNAs and provide the first evidence of the extensive roles of sRNAs in pneumococcal pathogenesis.
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Affiliation(s)
- Beth Mann
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Tim van Opijnen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Jianmin Wang
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Caroline Obert
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Yong-Dong Wang
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Robert Carter
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Daniel J. McGoldrick
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Granger Ridout
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Andrew Camilli
- Howard Hughes Medical Institute and Tufts University School of Medicine, Department of Molecular Biology and Microbiology, Boston, Massachusetts, United States of America
| | - Elaine I. Tuomanen
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Jason W. Rosch
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
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Croucher NJ, Harris SR, Barquist L, Parkhill J, Bentley SD. A high-resolution view of genome-wide pneumococcal transformation. PLoS Pathog 2012; 8:e1002745. [PMID: 22719250 PMCID: PMC3375284 DOI: 10.1371/journal.ppat.1002745] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 04/27/2012] [Indexed: 01/03/2023] Open
Abstract
Transformation is an important mechanism of microbial evolution through which bacteria have been observed to rapidly adapt in response to clinical interventions; examples include facilitating vaccine evasion and the development of penicillin resistance in the major respiratory pathogen Streptococcus pneumoniae. To characterise the process in detail, the genomes of 124 S. pneumoniae isolates produced through in vitro transformation were sequenced and recombination events detected. Those recombinations importing the selected marker were independent of unselected events elsewhere in the genome, the positions of which were not significantly affected by local sequence similarity between donor and recipient or mismatch repair processes. However, both types of recombinations were sometimes mosaic, with multiple non-contiguous segments originating from the same molecule of donor DNA. The lengths of the unselected events were exponentially distributed with a mean of 2.3 kb, implying that recombinations are stochastically resolved with a fixed per base probability of 4.4×10(-4) bp(-1). This distribution of recombination sizes, coupled with an observed under representation of large insertions within transferred sequence, suggests transformation has the potential to reduce the size of bacterial genomes, and is unlikely to act as an efficient mechanism for the uptake of accessory genomic loci.
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Affiliation(s)
- Nicholas J Croucher
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom.
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38
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Tissue-specific temporal exome capture revealed muscle-specific genes and SNPs in Indian buffalo (Bubalus bubalis). GENOMICS PROTEOMICS & BIOINFORMATICS 2012; 10:107-13. [PMID: 22768984 PMCID: PMC5054198 DOI: 10.1016/j.gpb.2012.05.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 12/28/2011] [Indexed: 11/20/2022]
Abstract
Whole genome sequencing of buffalo is yet to be completed, and in the near future it may not be possible to identify an exome (coding region of genome) through bioinformatics for designing probes to capture it. In the present study, we employed in solution hybridization to sequence tissue specific temporal exomes (TST exome) in buffalo. We utilized cDNA prepared from buffalo muscle tissue as a probe to capture TST exomes from the buffalo genome. This resulted in a prominent reduction of repeat sequences (up to 40%) and an enrichment of coding sequences (up to 60%). Enriched targets were sequenced on a 454 pyro-sequencing platform, generating 101,244 reads containing 24,127,779 high quality bases. The data revealed 40,100 variations, of which 403 were indels and 39,218 SNPs containing 195 nonsynonymous candidate SNPs in protein-coding regions. The study has indicated that 80% of the total genes identified from capture data were expressed in muscle tissue. The present study is the first of its kind to sequence TST exomes captured by use of cDNA molecules for SNPs found in the coding region without any prior sequence information of targeted molecules.
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Peterson ES, McCue LA, Schrimpe-Rutledge AC, Jensen JL, Walker H, Kobold MA, Webb SR, Payne SH, Ansong C, Adkins JN, Cannon WR, Webb-Robertson BJM. VESPA: software to facilitate genomic annotation of prokaryotic organisms through integration of proteomic and transcriptomic data. BMC Genomics 2012; 13:131. [PMID: 22480257 PMCID: PMC3364912 DOI: 10.1186/1471-2164-13-131] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 04/05/2012] [Indexed: 11/10/2022] Open
Abstract
Background The procedural aspects of genome sequencing and assembly have become relatively inexpensive, yet the full, accurate structural annotation of these genomes remains a challenge. Next-generation sequencing transcriptomics (RNA-Seq), global microarrays, and tandem mass spectrometry (MS/MS)-based proteomics have demonstrated immense value to genome curators as individual sources of information, however, integrating these data types to validate and improve structural annotation remains a major challenge. Current visual and statistical analytic tools are focused on a single data type, or existing software tools are retrofitted to analyze new data forms. We present Visual Exploration and Statistics to Promote Annotation (VESPA) is a new interactive visual analysis software tool focused on assisting scientists with the annotation of prokaryotic genomes though the integration of proteomics and transcriptomics data with current genome location coordinates. Results VESPA is a desktop Java™ application that integrates high-throughput proteomics data (peptide-centric) and transcriptomics (probe or RNA-Seq) data into a genomic context, all of which can be visualized at three levels of genomic resolution. Data is interrogated via searches linked to the genome visualizations to find regions with high likelihood of mis-annotation. Search results are linked to exports for further validation outside of VESPA or potential coding-regions can be analyzed concurrently with the software through interaction with BLAST. VESPA is demonstrated on two use cases (Yersinia pestis Pestoides F and Synechococcus sp. PCC 7002) to demonstrate the rapid manner in which mis-annotations can be found and explored in VESPA using either proteomics data alone, or in combination with transcriptomic data. Conclusions VESPA is an interactive visual analytics tool that integrates high-throughput data into a genomic context to facilitate the discovery of structural mis-annotations in prokaryotic genomes. Data is evaluated via visual analysis across multiple levels of genomic resolution, linked searches and interaction with existing bioinformatics tools. We highlight the novel functionality of VESPA and core programming requirements for visualization of these large heterogeneous datasets for a client-side application. The software is freely available at https://www.biopilot.org/docs/Software/Vespa.php.
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Affiliation(s)
- Elena S Peterson
- Scientific Data Management, Pacific Northwest National Laboratory, Richland, WA, USA
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40
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Pinto AC, Melo-Barbosa HP, Miyoshi A, Silva A, Azevedo V. Application of RNA-seq to reveal the transcript profile in bacteria. GENETICS AND MOLECULAR RESEARCH 2012; 10:1707-18. [PMID: 21863565 DOI: 10.4238/vol10-3gmr1554] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The large number of microbial genomes deposited in databanks has opened the door for in-depth studies of organisms, including post-genomics investigations. Thanks to new generation sequencing technology, these studies have made advances that have lead to extraordinary discoveries in bacterial transcriptomics. In this review, we describe bacterial RNA sequencing studies that use these new techniques. We also examined the advantages and biases of these new generation technologies; advances in bioinformatics make it possible to overcome the biases, providing interesting and surprising results.
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Affiliation(s)
- A C Pinto
- Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
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41
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Rakov AV, Ubukata K, Robinson DA. Population structure of hyperinvasive serotype 12F, clonal complex 218 Streptococcus pneumoniae revealed by multilocus boxB sequence typing. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2011; 11:1929-39. [PMID: 21888992 PMCID: PMC3230773 DOI: 10.1016/j.meegid.2011.08.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 08/16/2011] [Accepted: 08/17/2011] [Indexed: 01/13/2023]
Abstract
At least four outbreaks of invasive disease caused by serotype 12F, clonal complex 218 Streptococcus pneumoniae have occurred in the United States over the past two decades. We studied the population structure of this clonal complex using a sample of 203 outbreak and surveillance isolates that were collected over 22 years from 34 US states and eight other countries. Conventional multilocus sequence typing identified five types and distinguished a single outbreak from the others. To improve typing resolution, multilocus boxB sequence typing (MLBT) was developed from 10 variable boxB minisatellite loci. MLBT identified 86 types and distinguished between each of the four outbreaks. Diversity across boxB loci tended to be positively correlated with repeat array size and, overall, best fit the infinite alleles mutation model. Multilocus linkage disequilibrium was strong, but pairwise disequilibrium decreased with the physical distance between loci and was strongest in one large region of the chromosome, indicating recent recombinations. Two major clusters were identified in the sample, and they were differentiated geographically, as western and more easterly US clusters, and temporally, as clusters that predominated before and after the licensure of pneumococcal conjugate vaccines. The diversity and linkage disequilibrium within these two clusters also differed, suggesting different population dynamics. MLBT revealed hidden aspects of the population structure of these hyperinvasive pneumococci, and it may provide a useful adjunct tool for outbreak investigations, surveillance, and population genetics studies of other pneumococcal clonal complexes.
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Affiliation(s)
- Alexey V. Rakov
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS
| | - Kimiko Ubukata
- Laboratory of Molecular Epidemiology for Infectious Agents, Kitasato University, Tokyo, Japan
| | - D. Ashley Robinson
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS
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Abstract
Intergenic regions of prokaryotic genomes carry multiple copies of terminal inverted repeat (TIR) sequences, the nonautonomous miniature inverted-repeat transposable element (MITE). In addition, there are the repetitive extragenic palindromic (REP) sequences that fold into a small stem loop rich in G–C bonding. And the clustered regularly interspaced short palindromic repeats (CRISPRs) display similar small stem loops but are an integral part of a complex genetic element. Other classes of repeats such as the REP2 element do not have TIRs but show other signatures. With the current availability of a large number of whole-genome sequences, many new repeat elements have been discovered. These sequences display diverse properties. Some show an intimate linkage to integrons, and at least one encodes a small RNA. Many repeats are found fused with chromosomal open reading frames, and some are located within protein coding sequences. Small repeat units appear to work hand in hand with the transcriptional and/or post-transcriptional apparatus of the cell. Functionally, they are multifaceted, and this can range from the control of gene expression, the facilitation of host/pathogen interactions, or stimulation of the mammalian immune system. The CRISPR complex displays dramatic functions such as an acquired immune system that defends against invading viruses and plasmids. Evolutionarily, mobile repeat elements may have influenced a cycle of active versus inactive genes in ancestral organisms, and some repeats are concentrated in regions of the chromosome where there is significant genomic plasticity. Changes in the abundance of genomic repeats during the evolution of an organism may have resulted in a benefit to the cell or posed a disadvantage, and some present day species may reflect a purification process. The diverse structure, eclectic functions, and evolutionary aspects of repeat elements are described.
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Affiliation(s)
- Nicholas Delihas
- Department of Molecular Genetics and Microbiology, School of Medicine, State University of New York, Stony Brook, NY, USA.
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Genetic regulation of the yefM-yoeB toxin-antitoxin locus of Streptococcus pneumoniae. J Bacteriol 2011; 193:4612-25. [PMID: 21764929 DOI: 10.1128/jb.05187-11] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Type II (proteic) toxin-antitoxin systems (TAS) are ubiquitous among bacteria. In the chromosome of the pathogenic bacterium Streptococcus pneumoniae, there are at least eight putative TAS, one of them being the yefM-yoeB(Spn) operon studied here. Through footprinting analyses, we showed that purified YefM(Spn) antitoxin and the YefM-YoeB(Spn) TA protein complex bind to a palindrome sequence encompassing the -35 region of the main promoter (P(yefM2)) of the operon. Thus, the locus appeared to be negatively autoregulated with respect to P(yefM2), since YefM(Spn) behaved as a weak repressor with YoeB(Spn) as a corepressor. Interestingly, a BOX element, composed of a single copy (each) of the boxA and boxC subelements, was found upstream of promoter P(yefM2). BOX sequences are pneumococcal, perhaps mobile, genetic elements that have been associated with bacterial processes such as phase variation, virulence regulation, and genetic competence. In the yefM-yoeB(Spn) locus, the boxAC element provided an additional weak promoter, P(yefM1), upstream of P(yefM2) which was not regulated by the TA proteins. In addition, transcriptional fusions with a lacZ reporter gene showed that P(yefM1) was constitutive albeit weaker than P(yefM2). Intriguingly, the coupling of the boxAC element to P(yefM1) and yefM(Spn) in cis (but not in trans) led to transcriptional activation, indicating that the regulation of the yefM-yoeB(Spn) locus differs somewhat from that of other TA loci and may involve as yet unidentified elements. Conservation of the boxAC sequences in all available sequenced genomes of S. pneumoniae which contained the yefM-yoeB(Spn) locus suggested that its presence may provide a selective advantage to the bacterium.
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