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Torrillo PA, Lieberman TD. Reversions mask the contribution of adaptive evolution in microbiomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.14.557751. [PMID: 37745437 PMCID: PMC10515931 DOI: 10.1101/2023.09.14.557751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
When examining bacterial genomes for evidence of past selection, the results obtained depend heavily on the mutational distance between chosen genomes. Even within a bacterial species, genomes separated by larger mutational distances exhibit stronger evidence of purifying selection as assessed by d N / d S , the normalized ratio of nonsynonymous to synonymous mutations. This dependence on mutational distance, and thus time, has been proposed to arise from the inefficiency of purifying selection at removing weakly deleterious mutations. Here, we revisit this assumption in light of abundant genomes from gut microbiomes and show that a model of weak purifying selection that fits the data leads to problematic mutation accumulation. We propose an alternative model to explain the timescale dependence of d N / d S , in which constantly changing environmental pressures select for revertants of previously adaptive mutations. Reversions that sweep within-host populations are nearly guaranteed in microbiomes due to large population sizes, short generation times, and variable environments. Using analytical and simulation approaches, we fit the adaptive reversion model to d N / d S decay curves and obtain estimates of local adaptation that are realistic in the context of bacterial genomes. These results argue for interpreting low values of d N / d S with caution, as they may emerge even when adaptive sweeps are frequent. This work reframes an old observation in bacterial evolution, illustrates the potential of mutation reversions to shape genomic landscapes over time, and highlights the need for additional research on bacterial genomic evolution on short time scales.
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Affiliation(s)
- Paul A. Torrillo
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Tami D. Lieberman
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA
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2
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Earle SG, Lobanovska M, Lavender H, Tang C, Exley RM, Ramos-Sevillano E, Browning DF, Kostiou V, Harrison OB, Bratcher HB, Varani G, Tang CM, Wilson DJ, Maiden MCJ. Genome-wide association studies reveal the role of polymorphisms affecting factor H binding protein expression in host invasion by Neisseria meningitidis. PLoS Pathog 2021; 17:e1009992. [PMID: 34662348 PMCID: PMC8553145 DOI: 10.1371/journal.ppat.1009992] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/28/2021] [Accepted: 09/29/2021] [Indexed: 11/18/2022] Open
Abstract
Many invasive bacterial diseases are caused by organisms that are ordinarily harmless components of the human microbiome. Effective interventions against these microbes require an understanding of the processes whereby symbiotic or commensal relationships transition into pathology. Here, we describe bacterial genome-wide association studies (GWAS) of Neisseria meningitidis, a common commensal of the human respiratory tract that is nevertheless a leading cause of meningitis and sepsis. An initial GWAS discovered bacterial genetic variants, including single nucleotide polymorphisms (SNPs), associated with invasive meningococcal disease (IMD) versus carriage in several loci across the meningococcal genome, encoding antigens and other extracellular components, confirming the polygenic nature of the invasive phenotype. In particular, there was a significant peak of association around the fHbp locus, encoding factor H binding protein (fHbp), which promotes bacterial immune evasion of human complement by recruiting complement factor H (CFH) to the meningococcal surface. The association around fHbp with IMD was confirmed by a validation GWAS, and we found that the SNPs identified in the validation affected the 5' region of fHbp mRNA, altering secondary RNA structures, thereby increasing fHbp expression and enhancing bacterial escape from complement-mediated killing. This finding is consistent with the known link between complement deficiencies and CFH variation with human susceptibility to IMD. These observations demonstrate the importance of human and bacterial genetic variation across the fHbp:CFH interface in determining IMD susceptibility, the transition from carriage to disease.
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Affiliation(s)
- Sarah G. Earle
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
| | - Mariya Lobanovska
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Hayley Lavender
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Changyan Tang
- Department of Chemistry, University of Washington, Seattle, Washington United States of America
| | - Rachel M. Exley
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | | | - Douglas F. Browning
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Vasiliki Kostiou
- Nuffield Department of Clinical Medicine, Experimental Medicine Division, John Radcliffe Hospital, Oxford, United Kingdom
| | | | | | - Gabriele Varani
- Department of Chemistry, University of Washington, Seattle, Washington United States of America
- * E-mail: (GV); (CMT); (DJW); (MCJM)
| | - Christoph M. Tang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- * E-mail: (GV); (CMT); (DJW); (MCJM)
| | - Daniel J. Wilson
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom
- Department for Continuing Education, University of Oxford, Oxford, United Kingdom
- * E-mail: (GV); (CMT); (DJW); (MCJM)
| | - Martin C. J. Maiden
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- * E-mail: (GV); (CMT); (DJW); (MCJM)
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3
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Tzeng YL, Stephens DS. A Narrative Review of the W, X, Y, E, and NG of Meningococcal Disease: Emerging Capsular Groups, Pathotypes, and Global Control. Microorganisms 2021; 9:microorganisms9030519. [PMID: 33802567 PMCID: PMC7999845 DOI: 10.3390/microorganisms9030519] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 12/21/2022] Open
Abstract
Neisseria meningitidis, carried in the human nasopharynx asymptomatically by ~10% of the population, remains a leading cause of meningitis and rapidly fatal sepsis, usually in otherwise healthy individuals. The epidemiology of invasive meningococcal disease (IMD) varies substantially by geography and over time and is now influenced by meningococcal vaccines and in 2020–2021 by COVID-19 pandemic containment measures. While 12 capsular groups, defined by capsular polysaccharide structures, can be expressed by N. meningitidis, groups A, B, and C historically caused most IMD. However, the use of mono-, bi-, and quadrivalent-polysaccharide-conjugate vaccines, the introduction of protein-based vaccines for group B, natural disease fluctuations, new drugs (e.g., eculizumab) that increase meningococcal susceptibility, changing transmission dynamics and meningococcal evolution are impacting the incidence of the capsular groups causing IMD. While the ability to spread and cause illness vary considerably, capsular groups W, X, and Y now cause significant IMD. In addition, group E and nongroupable meningococci have appeared as a cause of invasive disease, and a nongroupable N. meningitidis pathotype of the hypervirulent clonal complex 11 is causing sexually transmitted urethritis cases and outbreaks. Carriage and IMD of the previously “minor” N. meningitidis are reviewed and the need for polyvalent meningococcal vaccines emphasized.
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Affiliation(s)
- Yih-Ling Tzeng
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - David S. Stephens
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA
- Correspondence: ; Tel.: +404-727-8357
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4
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Ait Mouss K, Razki A, Hong E, Zaki B, Maaloum F, Nzoyikorera N, Belabbes H, Elmdaghri N, Zerouali K. Epidemiological profile of Neisseria meningitidis in Casablanca, Morocco: 2010-2019. Access Microbiol 2020; 2:acmi000157. [PMID: 33195986 PMCID: PMC7656187 DOI: 10.1099/acmi.0.000157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 06/30/2020] [Indexed: 12/17/2022] Open
Abstract
Surveillance of invasive meningococcal diseases (IMD) must be carried out regularly and continuously in order to detect the emergence of strains of reduced susceptibility to antibiotics for therapeutic and prophylactic use and the appearance of new invasive clones. Molecular-typing approaches allow reliable traceability and powerful epidemiological analysis. This is an epidemiological study of Neisseria meningitidis causing meningitis in Casablanca, Morocco. The grouping was confirmed by PCR mainly on the isolates from cerebrospinal fluid (CSF). A total of 245 confirmed isolates of N .meningitidis were obtained between 2010 and 2019 of which 93 % are of group B. Overall, 24 % of all the isolates have a reduced susceptibility to penicillin G, but no resistance to penicillin G has been reported. All the isolated strains are susceptible to third-generation cephalosporins (3GCs). Genotyping by multilocus sequence typing (MLST) of a selection of 18 strains showed that the majority of isolates belong to the invasive clonal complex CC 32(9/18) followed by the CC 41/44(3/18).
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Affiliation(s)
- Khadija Ait Mouss
- Department of Microbiology, Faculty of Medicine and Pharmacy, Hassan II University of Casablanca, 19 rue Tarik Bnou Zyad, 20360, Casablanca, Morocco.,Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco.,Institut Pasteur du Maroc, 1, place louis pasteur, 20360, Casablanca, Morocco
| | - Aziza Razki
- Institut Pasteur du Maroc, 1, place louis pasteur, 20360, Casablanca, Morocco
| | - Eva Hong
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Bahija Zaki
- Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco
| | - Fakhreddine Maaloum
- Department of Microbiology, Faculty of Medicine and Pharmacy, Hassan II University of Casablanca, 19 rue Tarik Bnou Zyad, 20360, Casablanca, Morocco.,Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco
| | - Néhémie Nzoyikorera
- Department of Microbiology, Faculty of Medicine and Pharmacy, Hassan II University of Casablanca, 19 rue Tarik Bnou Zyad, 20360, Casablanca, Morocco.,Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco
| | - Houria Belabbes
- Department of Microbiology, Faculty of Medicine and Pharmacy, Hassan II University of Casablanca, 19 rue Tarik Bnou Zyad, 20360, Casablanca, Morocco.,Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco
| | - Naima Elmdaghri
- Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco
| | - Khalid Zerouali
- Department of Microbiology, Faculty of Medicine and Pharmacy, Hassan II University of Casablanca, 19 rue Tarik Bnou Zyad, 20360, Casablanca, Morocco.,Bacteriology-Virology and Hospital Hygiene Laboratory, University Hospital Centre Ibn Rochd, 1, Rue des Hôpitaux, 20100, Casablanca, Morocco
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Multicenter Hospital-Based Prospective Surveillance Study of Bacterial Agents Causing Meningitis and Seroprevalence of Different Serogroups of Neisseria meningitidis, Haemophilus influenzae Type b, and Streptococcus pneumoniae during 2015 to 2018 in Turkey. mSphere 2020; 5:5/2/e00060-20. [PMID: 32213620 PMCID: PMC7096621 DOI: 10.1128/msphere.00060-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Acute bacterial meningitis (ABM) is one of the most common life-threatening infections in children. The incidence and prevalence of ABM vary both geographically and temporally; therefore, surveillance systems are necessary to determine the accurate burden of ABM. The Turkish Meningitis Surveillance Group has been performing a hospital-based meningitis surveillance study since 2005 across several regions in Turkey. Meningococcus was the major ABM-causing agent during the 2015-to-2018 period, during which MenB was the dominant serogroup. The etiology of bacterial meningitis in Turkey changed after the implementation of conjugated vaccines against Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) in the Turkish National Immunization Program (NIP). Administration of Hib vaccine and PCV-7 (7-valent pneumococcal conjugate vaccine) was implemented in NIP in 2006 and 2009, respectively. In 2011, PCV-7 was replaced with PCV-13. Meningococcal vaccines have not yet been included in Turkish NIP. This prospective study comprised 27 hospitals located in seven regions of Turkey and represented 45% of the population. Children aged between 1 month and 18 years who were hospitalized with suspected meningitis were included. Cerebrospinal fluid (CSF) samples were collected, and bacterial identification was made according to the multiplex PCR assay results. During the study period, 994 children were hospitalized for suspected meningitis, and Hib (n = 3, 2.4%), S. pneumoniae (n = 33, 26.4%), and Neisseria meningitidis (n = 89, 71%) were detected in 125 samples. The most common meningococcal serogroup was MenB. Serogroup W comprised 13.9% (n = 5) and 7.5% (n = 4) of the meningococci in 2015 to 2016 and 2017 to 2018, respectively. Serogroup C was not detected. There were four deaths in the study; one was a pneumococcus case, and the others were serogroup B meningococcus cases. The epidemiology of meningococcal diseases has varied over time in Turkey. Differing from the previous surveillance periods, MenB was the most common serogroup in the 2015-to-2018 period. Meningococcal epidemiology is so dynamic that, for vaccination policies, close monitoring is crucial. IMPORTANCE Acute bacterial meningitis (ABM) is one of the most common life-threatening infections in children. The incidence and prevalence of ABM vary both geographically and temporally; therefore, surveillance systems are necessary to determine the accurate burden of ABM. The Turkish Meningitis Surveillance Group has been performing a hospital-based meningitis surveillance study since 2005 across several regions in Turkey. Meningococcus was the major ABM-causing agent during the 2015-to-2018 period, during which MenB was the dominant serogroup.
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Humbert MV, Christodoulides M. Atypical, Yet Not Infrequent, Infections with Neisseria Species. Pathogens 2019; 9:E10. [PMID: 31861867 PMCID: PMC7168603 DOI: 10.3390/pathogens9010010] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 12/24/2022] Open
Abstract
Neisseria species are extremely well-adapted to their mammalian hosts and they display unique phenotypes that account for their ability to thrive within niche-specific conditions. The closely related species N. gonorrhoeae and N. meningitidis are the only two species of the genus recognized as strict human pathogens, causing the sexually transmitted disease gonorrhea and meningitis and sepsis, respectively. Gonococci colonize the mucosal epithelium of the male urethra and female endo/ectocervix, whereas meningococci colonize the mucosal epithelium of the human nasopharynx. The pathophysiological host responses to gonococcal and meningococcal infection are distinct. However, medical evidence dating back to the early 1900s demonstrates that these two species can cross-colonize anatomical niches, with patients often presenting with clinically-indistinguishable infections. The remaining Neisseria species are not commonly associated with disease and are considered as commensals within the normal microbiota of the human and animal nasopharynx. Nonetheless, clinical case reports suggest that they can behave as opportunistic pathogens. In this review, we describe the diversity of the genus Neisseria in the clinical context and raise the attention of microbiologists and clinicians for more cautious approaches in the diagnosis and treatment of the many pathologies these species may cause.
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Affiliation(s)
- Maria Victoria Humbert
- Molecular Microbiology, School of Clinical and Experimental Sciences, University of Southampton, Faculty of Medicine, Southampton General Hospital, Southampton SO16 6YD, UK;
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7
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Genomic, Transcriptomic, and Phenotypic Analyses of Neisseria meningitidis Isolates from Disease Patients and Their Household Contacts. mSystems 2017; 2:mSystems00127-17. [PMID: 29152586 PMCID: PMC5686521 DOI: 10.1128/msystems.00127-17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 10/18/2017] [Indexed: 12/30/2022] Open
Abstract
Neisseria meningitidis causes meningococcal disease but is frequently carried in the throats of healthy individuals; the factors that determine whether invasive disease develops are not completely understood. We carried out detailed studies of isolates, collected from patients and their household contacts, to identify differences between commensal throat isolates and those that caused invasive disease. Though isolates were identical by laboratory typing methods, we uncovered many differences in their genomes, in gene expression, and in their interactions with host cells. In particular, we found that several carriage isolates had lost their type IV pili, a surprising finding since pili are often described as essential for colonization. However, loss of type IV pili correlated with reduced secretion of a proinflammatory cytokine, TNF-α, when meningococci were cocultured with human bronchial epithelial cells; hence, the loss of pili could provide an advantage to meningococci, by resulting in a dampened localized host immune response. Neisseria meningitidis (meningococcus) can cause meningococcal disease, a rapidly progressing and often fatal disease that can occur in previously healthy children. Meningococci are found in healthy carriers, where they reside in the nasopharynx as commensals. While carriage is relatively common, invasive disease, associated with hypervirulent strains, is a comparatively rare event. The basis of increased virulence in some strains is not well understood. New Zealand suffered a protracted meningococcal disease epidemic, from 1991 to 2008. During this time, a household carriage study was carried out in Auckland: household contacts of index meningococcal disease patients were swabbed for isolation of carriage strains. In many households, healthy carriers harbored strains identical, as determined by laboratory typing, to the ones infecting the associated patient. We carried out more-detailed analyses of carriage and disease isolates from a select number of households. We found that isolates, although indistinguishable by laboratory typing methods and likely closely related, had many differences. We identified multiple genome variants and transcriptional differences between isolates. These studies enabled the identification of two new phase-variable genes. We also found that several carriage strains had lost their type IV pili and that this loss correlated with reduced tumor necrosis factor alpha (TNF-α) expression when cultured with epithelial cells. While nonpiliated meningococcal isolates have been previously found in carriage strains, this is the first evidence of an association between type IV pili from meningococci and a proinflammatory epithelial response. We also identified potentially important metabolic differences between carriage and disease isolates, including the sulfate assimilation pathway. IMPORTANCENeisseria meningitidis causes meningococcal disease but is frequently carried in the throats of healthy individuals; the factors that determine whether invasive disease develops are not completely understood. We carried out detailed studies of isolates, collected from patients and their household contacts, to identify differences between commensal throat isolates and those that caused invasive disease. Though isolates were identical by laboratory typing methods, we uncovered many differences in their genomes, in gene expression, and in their interactions with host cells. In particular, we found that several carriage isolates had lost their type IV pili, a surprising finding since pili are often described as essential for colonization. However, loss of type IV pili correlated with reduced secretion of a proinflammatory cytokine, TNF-α, when meningococci were cocultured with human bronchial epithelial cells; hence, the loss of pili could provide an advantage to meningococci, by resulting in a dampened localized host immune response.
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8
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Gianchecchi E, Piccini G, Torelli A, Rappuoli R, Montomoli E. An unwanted guest:Neisseria meningitidis– carriage, risk for invasive disease and the impact of vaccination with insight on Italy incidence. Expert Rev Anti Infect Ther 2017; 15:689-701. [DOI: 10.1080/14787210.2017.1333422] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Giulia Piccini
- VisMederi Srl, Siena, Italy
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Alessandro Torelli
- VisMederi Srl, Siena, Italy
- Department of Life Sciences, University of Siena, Siena, Italy
| | | | - Emanuele Montomoli
- VisMederi Srl, Siena, Italy
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
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9
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Ampattu BJ, Hagmann L, Liang C, Dittrich M, Schlüter A, Blom J, Krol E, Goesmann A, Becker A, Dandekar T, Müller T, Schoen C. Transcriptomic buffering of cryptic genetic variation contributes to meningococcal virulence. BMC Genomics 2017; 18:282. [PMID: 28388876 PMCID: PMC5383966 DOI: 10.1186/s12864-017-3616-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 03/10/2017] [Indexed: 01/06/2023] Open
Abstract
Background Commensal bacteria like Neisseria meningitidis sometimes cause serious disease. However, genomic comparison of hyperinvasive and apathogenic lineages did not reveal unambiguous hints towards indispensable virulence factors. Here, in a systems biological approach we compared gene expression of the invasive strain MC58 and the carriage strain α522 under different ex vivo conditions mimicking commensal and virulence compartments to assess the strain-specific impact of gene regulation on meningococcal virulence. Results Despite indistinguishable ex vivo phenotypes, both strains differed in the expression of over 500 genes under infection mimicking conditions. These differences comprised in particular metabolic and information processing genes as well as genes known to be involved in host-damage such as the nitrite reductase and numerous LOS biosynthesis genes. A model based analysis of the transcriptomic differences in human blood suggested ensuing metabolic flux differences in energy, glutamine and cysteine metabolic pathways along with differences in the activation of the stringent response in both strains. In support of the computational findings, experimental analyses revealed differences in cysteine and glutamine auxotrophy in both strains as well as a strain and condition dependent essentiality of the (p)ppGpp synthetase gene relA and of a short non-coding AT-rich repeat element in its promoter region. Conclusions Our data suggest that meningococcal virulence is linked to transcriptional buffering of cryptic genetic variation in metabolic genes including global stress responses. They further highlight the role of regulatory elements for bacterial virulence and the limitations of model strain approaches when studying such genetically diverse species as N. meningitidis. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3616-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Biju Joseph Ampattu
- Institute for Hygiene and Microbiology, Joseph-Schneider-Straße 2, University of Würzburg, 97080, Würzburg, Germany
| | - Laura Hagmann
- Institute for Hygiene and Microbiology, Joseph-Schneider-Straße 2, University of Würzburg, 97080, Würzburg, Germany
| | - Chunguang Liang
- Department of Bioinformatics, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Marcus Dittrich
- Department of Bioinformatics, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany.,Department of Human Genetics, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Andreas Schlüter
- Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstr. 27, 33615, Bielefeld, Germany
| | - Jochen Blom
- Institute for Bioinformatics and Systems Biology, Justus Liebig University Gießen, Heinrich-Buff-Ring 58, 35392, Gießen, Germany
| | - Elizaveta Krol
- LOEWE-Center for Synthetic Microbiology, Hans-Meerwein-Straße, 35032, Marburg, Germany
| | - Alexander Goesmann
- Institute for Bioinformatics and Systems Biology, Justus Liebig University Gießen, Heinrich-Buff-Ring 58, 35392, Gießen, Germany
| | - Anke Becker
- LOEWE-Center for Synthetic Microbiology, Hans-Meerwein-Straße, 35032, Marburg, Germany
| | - Thomas Dandekar
- Department of Bioinformatics, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Tobias Müller
- Department of Bioinformatics, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Christoph Schoen
- Institute for Hygiene and Microbiology, Joseph-Schneider-Straße 2, University of Würzburg, 97080, Würzburg, Germany.
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10
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Metabolic shift in the emergence of hyperinvasive pandemic meningococcal lineages. Sci Rep 2017; 7:41126. [PMID: 28112239 PMCID: PMC5282872 DOI: 10.1038/srep41126] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 12/15/2016] [Indexed: 12/15/2022] Open
Abstract
Hyperinvasive lineages of Neisseria meningitidis, which persist despite extensive horizontal genetic exchange, are a major cause of meningitis and septicaemia worldwide. Over the past 50 years one such lineage of meningococci, known as serogroup A, clonal complex 5 (A:cc5), has caused three successive pandemics, including epidemics in sub-Saharan Africa. Although the principal antigens that invoke effective immunity have remained unchanged, distinct A:cc5 epidemic clones have nevertheless emerged. An analysis of whole genome sequence diversity among 153 A:cc5 isolates identified eleven genetic introgression events in the emergence of the epidemic clones, which primarily involved variants of core genes encoding metabolic processes. The acquired DNA was identical to that found over many years in other, unrelated, hyperinvasive meningococci, suggesting that the epidemic clones emerged by acquisition of pre-existing metabolic gene variants, rather than ‘virulence’ associated or antigen-encoding genes. This is consistent with mathematical models which predict the association of transmission fitness with the emergence and maintenance of virulence in recombining commensal organisms.
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11
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Distribution of the type III DNA methyltransferases modA, modB and modD among Neisseria meningitidis genotypes: implications for gene regulation and virulence. Sci Rep 2016; 6:21015. [PMID: 26867950 PMCID: PMC4751487 DOI: 10.1038/srep21015] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 01/14/2016] [Indexed: 12/03/2022] Open
Abstract
Neisseria meningitidis is a human-specific bacterium that varies in invasive potential. All meningococci are carried in the nasopharynx, and most genotypes are very infrequently associated with invasive meningococcal disease; however, those belonging to the ‘hyperinvasive lineages’ are more frequently associated with sepsis or meningitis. Genome content is highly conserved between carriage and disease isolates, and differential gene expression has been proposed as a major determinant of the hyperinvasive phenotype. Three phase variable DNA methyltransferases (ModA, ModB and ModD), which mediate epigenetic regulation of distinct phase variable regulons (phasevarions), have been identified in N. meningitidis. Each mod gene has distinct alleles, defined by their Mod DNA recognition domain, and these target and methylate different DNA sequences, thereby regulating distinct gene sets. Here 211 meningococcal carriage and >1,400 disease isolates were surveyed for the distribution of meningococcal mod alleles. While modA11-12 and modB1-2 were found in most isolates, rarer alleles (e.g., modA15, modB4, modD1-6) were specific to particular genotypes as defined by clonal complex. This suggests that phase variable Mod proteins may be associated with distinct phenotypes and hence invasive potential of N. meningitidis strains.
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12
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Prevalence, Risk Factors and Molecular Characteristics of Meningococcal Carriage Among Brazilian Adolescents. Pediatr Infect Dis J 2015. [PMID: 26222063 DOI: 10.1097/inf.0000000000000853] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND In 2010, introduction of the meningococcal C conjugate vaccine in Brazil for children <2 years provided an immediate reduction in the incidence rates of disease among the age groups targeted for the vaccine, but no early impact was observed in unvaccinated age groups. Knowledge about meningococcal carriage is crucial for improving our understanding of the disease epidemiology and for designing effective vaccination programs. Taking in account the very limited published data currently available describing meningococcal carriage in Brazil, we performed a study to evaluate the prevalence of Neisseria meningitidis carriage among adolescent students. METHODS A cross-sectional study was conducted in 2012 to assess the prevalence of meningococcal carriage among a representative sample of 1208 students 11-19 years of age in Campinas, Brazil. Genotypic and phenotypic characterization of isolated carriage strains and the effect of potential risk factors for carriage were also analyzed. RESULTS The overall carriage prevalence was 9.9% (95% confidence interval, 8.3-11.8%), with dominance of serogroup C (1.32%), followed by serogroups B (0.99%), E (0.74%), Y (0.49%) and W (0.25%). A lower level of education of the parents was independently associated with a higher risk of carriage. A high diversity of genotypes was found among carriage strains. CONCLUSIONS The evidence gathered during this study provides estimates of carriage prevalence in Brazilian adolescents, showing an unusually high dominance of serogroup C. These results have important implications in future strategies to optimize the impact of the current meningococcal C vaccination program in Brazil.
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Guillemi EC, Tomassone L, Farber MD. Tick-borne Rickettsiales: Molecular tools for the study of an emergent group of pathogens. J Microbiol Methods 2015; 119:87-97. [PMID: 26471201 DOI: 10.1016/j.mimet.2015.10.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 10/09/2015] [Accepted: 10/09/2015] [Indexed: 12/16/2022]
Abstract
The use of molecular techniques in recent years has enhanced the sensitivity and specificity of the diagnosis of Rickettsiales, a bacterial order which includes significant emerging and re-emerging pathogens of humans and animals. Molecular detection enables the accurate identification at the species level, providing additional information on the epidemiology and course of the clinical cases. Moreover, PCR and enzyme restriction analysis of the vector blood meal can be employed to study the tick feeding source and possibly identify pathogen's reservoir. Here, we review the molecular tools available for the identification and characterization of tick-borne bacteria from the genera Rickettsia, Ehrlichia and Anaplasma and for the study of ticks feeding behavior. We summarize the significant criteria for taxonomic identification of Rickettsiales species and propose a procedure algorithm for the classification of bacterial isolates as members of this order.
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Affiliation(s)
- Eliana C Guillemi
- Inst. de Biotecnología, INTA Castelar. Los Reseros y N. Repetto, 1686 Hurlingham, Buenos Aires, Argentina.
| | - Laura Tomassone
- Dipartimento di Scienze Veterinarie, Università degli Studi di Torino, Largo Braccini 2, 10095 Grugliasco, Torino, Italy
| | - Marisa D Farber
- Inst. de Biotecnología, INTA Castelar. Los Reseros y N. Repetto, 1686 Hurlingham, Buenos Aires, Argentina
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Besbes A, Le Goff S, Antunes A, Terrade A, Hong E, Giorgini D, Taha MK, Deghmane AE. Hyperinvasive Meningococci Induce Intra-nuclear Cleavage of the NF-κB Protein p65/RelA by Meningococcal IgA Protease. PLoS Pathog 2015; 11:e1005078. [PMID: 26241037 PMCID: PMC4524725 DOI: 10.1371/journal.ppat.1005078] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 07/10/2015] [Indexed: 11/30/2022] Open
Abstract
Differential modulation of NF-κB during meningococcal infection is critical in innate immune response to meningococcal disease. Non-invasive isolates of Neisseria meningitidis provoke a sustained NF-κB activation in epithelial cells. However, the hyperinvasive isolates of the ST-11 clonal complex (ST-11) only induce an early NF-κB activation followed by a sustained activation of JNK and apoptosis. We show that this temporal activation of NF-κB was caused by specific cleavage at the C-terminal region of NF-κB p65/RelA component within the nucleus of infected cells. This cleavage was mediated by the secreted 150 kDa meningococcal ST-11 IgA protease carrying nuclear localisation signals (NLS) in its α-peptide moiety that allowed efficient intra-nuclear transport. In a collection of non-ST-11 healthy carriage isolates lacking NLS in the α-peptide, secreted IgA protease was devoid of intra-nuclear transport. This part of iga polymorphism allows non-invasive isolates lacking NLS, unlike hyperinvasive ST-11 isolates of N. meningitides habouring NLS in their α-peptide, to be carried asymptomatically in the human nasopharynx through selective eradication of their ability to induce apoptosis in infected epithelial cells. Strains of Neisseria meningitidis isolated from patients induce apoptotic cell death, whereas strains isolated from healthy carriage isolates do not. Part of the difference has been shown to arise from differential modulation of NF-κB during meningococcal infection. While non-invasive isolates of Neisseria meningitidis provoke a sustained NF-κB activation in epithelial cells, hyperinvasive isolates only induce an early NF-κB activation followed by a sustained activation of JNK and apoptosis. Here, we elucidate the mechanism conferring this differential modulation, specifically showing that ST-11 hyperinvasive isolates promote specific cleavage of NF-κB p65/RelA component in a manner dependent on the secreted IgA protease. This cleavage occurs within the nuclear compartment. Secreted IgA protease from non-invasive isolates was unable to reach the nuclear compartment of infected cells, resulting in a sustained activation of NF-κB activity and subsequent cytoprotective effect. Modulation of NF-κB-related signaling is likely a double-edged sword to decide the fate of meningococcal infection.
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Affiliation(s)
- Anissa Besbes
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Salomé Le Goff
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Ana Antunes
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Aude Terrade
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Eva Hong
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Dario Giorgini
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Muhamed-Kheir Taha
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
- * E-mail: (MKT); (AED)
| | - Ala-Eddine Deghmane
- Institut Pasteur, Invasive Bacterial Infections Unit, Paris, France
- * E-mail: (MKT); (AED)
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Jolley KA, Maiden MCJ. Using multilocus sequence typing to study bacterial variation: prospects in the genomic era. Future Microbiol 2015; 9:623-30. [PMID: 24957089 DOI: 10.2217/fmb.14.24] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Multilocus sequence typing (MLST) indexes the sequence variation present in a small number (usually seven) of housekeeping gene fragments located around the bacterial genome. Unique alleles at these loci are assigned arbitrary integer identifiers, which effectively summarizes the variation present in several thousand base pairs of genome sequence information as a series of numbers. Comparing bacterial isolates using allele-based methods efficiently corrects for the effects of lateral gene transfer present in many bacterial populations and is computationally efficient. This 'gene-by-gene' approach can be applied to larger collections of loci, such as the ribosomal protein genes used in ribosomal MLST (rMLST), up to and including the complete set of coding sequences present in a genome, whole-genome MLST (wgMLST), providing scalable, efficient and readily interpreted genome analysis.
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Affiliation(s)
- Keith A Jolley
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
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Guillemi EC, Ruybal P, Lia V, Gonzalez S, Lew S, Zimmer P, Lopez Arias L, Rodriguez JL, Rodriguez SY, Frutos R, Wilkowsky SE, Farber MD. Development of a Multilocus Sequence Typing scheme for the study of Anaplasma marginale population structure over space and time. INFECTION GENETICS AND EVOLUTION 2015; 30:186-194. [DOI: 10.1016/j.meegid.2014.12.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/21/2014] [Accepted: 12/22/2014] [Indexed: 12/11/2022]
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Abstract
Neisseria meningitidis, the cause of meningococcal disease, has been the subject of sophisticated molecular epidemiological investigation as a consequence of the significant public health threat posed by this organism. The use of multilocus sequence typing and whole genome sequencing classifies the organism into clonal complexes. Extensive phenotypic, genotypic and epidemiological information is available on the PubMLST website. The human nasopharynx is the sole ecological niche of this species, and carrier isolates show extensive genetic diversity as compared with hyperinvasive lineages. Horizontal gene exchange and recombinant events within the meningococcal genome during residence in the human nasopharynx result in antigenic diversity even within clonal complexes, so that individual clones may express, for example, more than one capsular polysaccharide (serogroup). Successful clones are capable of wide global dissemination, and may be associated with explosive epidemics of invasive disease.
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Affiliation(s)
- R C Read
- Clinical and Experimental Sciences and NIHR Respiratory Biomedical Research Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
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Whelan J, Bambini S, Biolchi A, Brunelli B, Robert–Du Ry van Beest Holle M. Outbreaks of meningococcal B infection and the 4CMenB vaccine: historical and future perspectives. Expert Rev Vaccines 2015; 14:713-36. [DOI: 10.1586/14760584.2015.1004317] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Ren X, MacKichan JK. Disease-associated Neisseria meningitidis isolates inhibit wound repair in respiratory epithelial cells in a type IV pilus-independent manner. Infect Immun 2014; 82:5023-34. [PMID: 25225250 PMCID: PMC4249276 DOI: 10.1128/iai.02001-14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 09/12/2014] [Indexed: 12/28/2022] Open
Abstract
Neisseria meningitidis is the causative agent of meningococcal disease. Onset of meningococcal disease can be extremely rapid and can kill within a matter of hours. However, although a much-feared pathogen, Neisseria meningitidis is frequently found in the nasopharyngeal mucosae of healthy carriers. The bacterial factors that distinguish disease- from carriage-associated meningococci are incompletely understood. Evidence suggesting that disruptions to the nasopharynx may increase the risk of acquiring meningococcal disease led us to evaluate the ability of disease- and carriage-associated meningococcal isolates to inhibit cell migration, using an in vitro assay for wound repair. We found that disease-associated isolates in our collection inhibited wound closure, while carriage-associated isolates were more variable, with many isolates not inhibiting wound repair at all. For isolates selected for further study, we found that actin morphology, such as presence of lamellipodia, correlated with cell migration. We demonstrated that multiple meningococcal virulence factors, including the type IV pili, are dispensable for inhibition of wound repair. Inhibition of wound repair was also shown to be an active process, i.e., requiring live bacteria undergoing active protein synthesis.
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Affiliation(s)
- Xiaoyun Ren
- Institute of Environmental Science and Research, Kenepuru Science Centre, Porirua, New Zealand School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Joanna K MacKichan
- Institute of Environmental Science and Research, Kenepuru Science Centre, Porirua, New Zealand School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand Centre for Biodiscovery, Victoria University of Wellington, Wellington, New Zealand
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Simonis A, Hebling S, Gulbins E, Schneider-Schaulies S, Schubert-Unkmeir A. Differential activation of acid sphingomyelinase and ceramide release determines invasiveness of Neisseria meningitidis into brain endothelial cells. PLoS Pathog 2014; 10:e1004160. [PMID: 24945304 PMCID: PMC4055770 DOI: 10.1371/journal.ppat.1004160] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 04/20/2014] [Indexed: 12/02/2022] Open
Abstract
The interaction with brain endothelial cells is central to the pathogenicity of Neisseria meningitidis infections. Here, we show that N. meningitidis causes transient activation of acid sphingomyelinase (ASM) followed by ceramide release in brain endothelial cells. In response to N. meningitidis infection, ASM and ceramide are displayed at the outer leaflet of the cell membrane and condense into large membrane platforms which also concentrate the ErbB2 receptor. The outer membrane protein Opc and phosphatidylcholine-specific phospholipase C that is activated upon binding of the pathogen to heparan sulfate proteoglycans, are required for N. meningitidis-mediated ASM activation. Pharmacologic or genetic ablation of ASM abrogated meningococcal internalization without affecting bacterial adherence. In accordance, the restricted invasiveness of a defined set of pathogenic isolates of the ST-11/ST-8 clonal complex into brain endothelial cells directly correlated with their restricted ability to induce ASM and ceramide release. In conclusion, ASM activation and ceramide release are essential for internalization of Opc-expressing meningococci into brain endothelial cells, and this segregates with invasiveness of N. meningitidis strains. Neisseria meningitidis, an obligate human pathogen, is a causative agent of septicemia and meningitis worldwide. Meningococcal infection manifests in a variety of forms, including meningitis, meningococcemia with meningitis or meningococcemia without obvious meningitis. The interaction of N. meningitidis with human cells lining the blood vessels of the blood-cerebrospinal fluid barrier is a prerequisite for the development of meningitis. As a major pathogenicity factor, the meningococcal outer membrane protein Opc enhances bacterial entry into brain endothelial cells, however, mechanisms underlying trapping of receptors and signaling molecules following this interaction remained elusive. We now show that Opc-expressing meningococci activate acid sphingomyelinase (ASM) in brain endothelial cells, which hydrolyses sphingomyelin to cause ceramide release and formation of extended ceramide-enriched membrane platforms wherein ErbB2, an important receptor involved in bacterial uptake, clusters. Mechanistically, ASM activation relied on binding of N. meningitidis to its attachment receptor, HSPG, followed by activation of PC-PLC. Meningococcal isolates of the ST-11 clonal complex, which are reported to be more likely to cause severe sepsis, but rarely meningitis, barely invaded brain endothelial cells and revealed a highly restricted ability to induce ASM and ceramide release. Thus, our results unravel a differential activation of the ASM/ceramide system by the species N. meningitidis determining its invasiveness into brain endothelial cells.
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Affiliation(s)
- Alexander Simonis
- Institute of Hygiene and Microbiology, University of Wuerzburg, Wuerzburg, Germany
| | - Sabrina Hebling
- Institute of Hygiene and Microbiology, University of Wuerzburg, Wuerzburg, Germany
| | - Erich Gulbins
- Department of Molecular Medicine, University of Essen, Essen, Germany
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Implications of differential age distribution of disease-associated meningococcal lineages for vaccine development. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:847-53. [PMID: 24695776 PMCID: PMC4054250 DOI: 10.1128/cvi.00133-14] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
New vaccines targeting meningococci expressing serogroup B polysaccharide have been developed, with some being licensed in Europe. Coverage depends on the distribution of disease-associated genotypes, which may vary by age. It is well established that a small number of hyperinvasive lineages account for most disease, and these lineages are associated with particular antigens, including vaccine candidates. A collection of 4,048 representative meningococcal disease isolates from 18 European countries, collected over a 3-year period, were characterized by multilocus sequence typing (MLST). Age data were available for 3,147 isolates. The proportions of hyperinvasive lineages, identified as particular clonal complexes (ccs) by MLST, differed among age groups. Subjects <1 year of age experienced lower risk of sequence type 11 (ST-11) cc, ST-32 cc, and ST-269 cc disease and higher risk of disease due to unassigned STs, 1- to 4-year-olds experienced lower risk of ST-11 cc and ST-32 cc disease, 5- to 14-year-olds were less likely to experience ST-11 cc and ST-269 cc disease, and ≥25-year-olds were more likely to experience disease due to less common ccs and unassigned STs. Younger and older subjects were vulnerable to a more diverse set of genotypes, indicating the more clonal nature of genotypes affecting adolescents and young adults. Knowledge of temporal and spatial diversity and the dynamics of meningococcal populations is essential for disease control by vaccines, as coverage is lineage specific. The nonrandom age distribution of hyperinvasive lineages has consequences for the design and implementation of vaccines, as different variants, or perhaps targets, may be required for different age groups.
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Soriano-Gabarró M, Wolter J, Hogea C, Vyse A. Carriage ofNeisseria meningitidisin Europe: a review of studies undertaken in the region. Expert Rev Anti Infect Ther 2014; 9:761-74. [DOI: 10.1586/eri.11.89] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Abio A, Neal KR, Beck CR. An epidemiological review of changes in meningococcal biology during the last 100 years. Pathog Glob Health 2013; 107:373-80. [PMID: 24392681 PMCID: PMC4083158 DOI: 10.1179/2047773213y.0000000119] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AIM The aim of this study was to assess changes in trends of meningococcal disease and strain diversity of Neisseria meningitidis in Europe, South America, and Africa over the last 100 years. METHODS Healthcare databases and sources of grey literature were searched in 2012 and records were screened against the protocol eligibility criteria using a three-stage sifting process. Studies included in the review were subject to data extraction. Results were summarised using a narrative approach. RESULTS Serogroup A was the dominant cause of invasive meningococcal disease in Europe before and during World Wars I and II. Whilst serogroup B has been dominant from the 1970s in Europe and the 1980s in South America, outbreaks have emerged associated with serogroups W135 and Y in the twenty-first century. There has been a shift in the age groups affected by invasive meningococcal disease with an increase in incidence among the elderly associated with serogroup Y and a decline in serogroup C among adolescent populations. Recent outbreaks of serogroup W135 have occurred in some countries in South America. The epidemiological trend of invasive meningococcal disease has remained largely static across Africa and dominated by serogroup A although recently serogroups X and W135 have accounted for a large proportion of morbidity and mortality. CONCLUSION The epidemiology of N. meningitidis has been dynamic in Europe and South America especially over the last 30 years. Routine vaccination with serogroup C vaccines has led to reduced carriage and incidence of invasive meningococcal disease and herd immunity.
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Hanincova K, Mukherjee P, Ogden NH, Margos G, Wormser GP, Reed KD, Meece JK, Vandermause MF, Schwartz I. Multilocus sequence typing of Borrelia burgdorferi suggests existence of lineages with differential pathogenic properties in humans. PLoS One 2013; 8:e73066. [PMID: 24069170 PMCID: PMC3775742 DOI: 10.1371/journal.pone.0073066] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 07/17/2013] [Indexed: 11/18/2022] Open
Abstract
The clinical manifestations of Lyme disease, caused by Borrelia burgdorferi, vary considerably in different patients, possibly due to infection by strains with varying pathogenicity. Both rRNA intergenic spacer and ospC typing methods have proven to be useful tools for categorizing B. burgdorferi strains that vary in their tendency to disseminate in humans. Neither method, however, is suitable for inferring intraspecific relationships among strains that are important for understanding the evolution of pathogenicity and the geographic spread of disease. In this study, multilocus sequence typing (MLST) was employed to investigate the population structure of B. burgdorferi recovered from human Lyme disease patients. A total of 146 clinical isolates from patients in New York and Wisconsin were divided into 53 sequence types (STs). A goeBURST analysis, that also included previously published STs from the northeastern and upper Midwestern US and adjoining areas of Canada, identified 11 major and 3 minor clonal complexes, as well as 14 singletons. The data revealed that patients from New York and Wisconsin were infected with two distinct, but genetically and phylogenetically closely related, populations of B. burgdorferi. Importantly, the data suggest the existence of B. burgdorferi lineages with differential capabilities for dissemination in humans. Interestingly, the data also indicate that MLST is better able to predict the outcome of localized or disseminated infection than is ospC typing.
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Affiliation(s)
- Klara Hanincova
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
- * E-mail:
| | - Priyanka Mukherjee
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
| | - Nicholas H. Ogden
- Zoonoses Division, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada
| | - Gabriele Margos
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich and National Reference Centre for Borrelia at the Bavarian Health and Food Safety Authority, Oberschleissheim, Germany
| | - Gary P. Wormser
- Division of Infectious Diseases, Department of Medicine, New York Medical College, Valhalla, New York, United States of America
| | - Kurt D. Reed
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Jennifer K. Meece
- Marshfield Clinic Research Foundation, Marshfield, Wisconsin, United States of America
| | - Mary F. Vandermause
- Marshfield Clinic Research Foundation, Marshfield, Wisconsin, United States of America
| | - Ira Schwartz
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
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Watkins ER, Maiden MCJ. Persistence of hyperinvasive meningococcal strain types during global spread as recorded in the PubMLST database. PLoS One 2012; 7:e45349. [PMID: 23028953 PMCID: PMC3460945 DOI: 10.1371/journal.pone.0045349] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 08/15/2012] [Indexed: 01/10/2023] Open
Abstract
Neisseria meningitidis is a major cause of septicaemia and meningitis worldwide. Most disease in Europe, the Americas and Australasia is caused by meningococci expressing serogroup B capsules, but no vaccine against this polysaccharide exists. Potential candidates for 'serogroup B substitute' vaccines are outer membrane protein antigens including the typing antigens PorA and FetA. The web-accessible PubMLST database (www.pubmlst.org) was used to investigate the temporal and geographical patterns of associations among PorA and FetA protein variants and lineages defined by combinations of housekeeping genes, known as clonal complexes. The sample contained 3460 isolates with genotypic information from 57 countries over a 74 year period. Although shifting associations among antigen variants and clonal complexes were evident, a subset of strain types associated with several serogroups persisted for decades and proliferated globally. Genetic stability among outer membrane proteins of serogroup A meningococci has been described previously, but here long-lived genetic associations were also observed among meningococci belonging to serogroups B and C. The patterns of variation were consistent with behaviour predicted by models that invoke inter-strain competition mediated by immune selection. There was also substantial geographic and temporal heterogeneity in antigenic repertoires, providing both opportunities and challenges for the design of broad coverage protein-based meningococcal vaccines.
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Clonal analysis of Neisseria meningitidis serogroup B strains in South Africa, 2002 to 2006: emergence of new clone ST-4240/6688. J Clin Microbiol 2012; 50:3678-86. [PMID: 22972827 DOI: 10.1128/jcm.01079-12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
From August 1999 through July 2002, hyperinvasive Neisseria meningitidis serogroup B (MenB) clonal complexes (CCs), namely, ST-32/ET-5 (CC32) and ST-41/44/lineage 3 (CC41/44), were predominant in the Western Cape Province of South Africa. This study analyzed MenB invasive isolates from a national laboratory-based surveillance system that were collected from January 2002 through December 2006. Isolates were characterized by pulsed-field gel electrophoresis (PFGE) (n = 302), and multilocus sequence typing (MLST) and PorA and FetA typing were performed on randomly selected isolates (34/302, 11%). In total, 2,400 cases were reported, with the highest numbers from Gauteng Province (1,307/2,400, 54%) and Western Cape Province (393/2,400, 16%); 67% (1,617/2,400) had viable isolates and 19% (307/1,617) were identified as serogroup B. MenB incidence remained stable over time (P = 0.77) (average incidence, 0.13/100,000 population [range, 0.10 to 0.16/100,000 population]). PFGE (302/307, 98%) divided isolates (206/302, 68%) into 13 clusters and 96 outliers. The largest cluster, B1, accounted for 25% of isolates (76/302) over the study period; its prevalence decreased from 43% (20/47) in 2002 to 13% (8/62) in 2006 (P < 0.001), and it was common in the Western Cape (58/76, 76%). Clusters B2 and B3 accounted for 10% (31/302) and 6% (19/302), respectively, and showed no significant change over time and were predominant in Gauteng. Randomly selected isolates from clusters B1, B2, and B3 belonged to CC32, CC41/44, and the new CC4240/6688, respectively. Overall, 15 PorA and 12 FetA types were identified. MenB isolates were mostly diverse with no single dominant clone; however, CC32 and CC41/44 accounted for 35% and the new CC4240/6688 was the third most prevalent clone.
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Laboratory-based surveillance of Neisseria meningitidis isolates from disease cases in Latin American and Caribbean countries, SIREVA II 2006-2010. PLoS One 2012; 7:e44102. [PMID: 22952888 PMCID: PMC3431326 DOI: 10.1371/journal.pone.0044102] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 07/30/2012] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Published data on the epidemiology of meningococcal disease in Latin America and the Caribbean region is scarce and, when available, it is often published in Spanish and/or in non-peer-reviewed journals, making it difficult for the international scientific community to have access. METHODS Laboratory data on 4,735 Neisseria meningitidis strains was collected and reported by the National Reference Laboratories in 19 Latin American countries and the Caribbean Epidemiology Centre (CAREC) between 2006 and 2010 as part of the work carried out by the SIREVA II network. Serogroup and MIC to penicillin, rifampin and chloramphenicol were determined. RESULTS Isolates were mainly obtained from patients <5 years, but each year around 25% of isolates came from adult patients. Serogroup distribution was highly variable among countries. Serogroup C was the main cause of disease in Brazil; the majority of disease seen in the Southern cone was caused by serogroup B, but serogroup W135 strains have increased in recent years. In the Andean and Mexico, Central America and Caribbean regions, serogroups B and C were equally present, and serogroup Y was frequently isolated. Isolates were generally susceptible to chloramphenicol, penicillin and rifampin, but almost 60% of isolates characterized in Southern cone countries presented intermediate resistance to penicillin. Five rifampin-resistant isolates have been isolated in Uruguay and Brazil. CONCLUSIONS Serogroup distribution is highly variable among countries, but some geographic structuring can be inferred from these data. Epidemiological and laboratory data are scarce among Andean and Mexico, Central America and Caribbean countries. Evaluation and implementation of corrective measures on disease surveillance and reporting systems and the implementation of molecular diagnostic techniques and molecular characterization on meningococcal isolates are advised.
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Ion torrent personal genome machine sequencing for genomic typing of Neisseria meningitidis for rapid determination of multiple layers of typing information. J Clin Microbiol 2012; 50:1889-94. [PMID: 22461678 DOI: 10.1128/jcm.00038-12] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Neisseria meningitidis causes invasive meningococcal disease in infants, toddlers, and adolescents worldwide. DNA sequence-based typing, including multilocus sequence typing, analysis of genetic determinants of antibiotic resistance, and sequence typing of vaccine antigens, has become the standard for molecular epidemiology of the organism. However, PCR of multiple targets and consecutive Sanger sequencing provide logistic constraints to reference laboratories. Taking advantage of the recent development of benchtop next-generation sequencers (NGSs) and of BIGSdb, a database accommodating and analyzing genome sequence data, we therefore explored the feasibility and accuracy of Ion Torrent Personal Genome Machine (PGM) sequencing for genomic typing of meningococci. Three strains from a previous meningococcus serogroup B community outbreak were selected to compare conventional typing results with data generated by semiconductor chip-based sequencing. In addition, sequencing of the meningococcal type strain MC58 provided information about the general performance of the technology. The PGM technology generated sequence information for all target genes addressed. The results were 100% concordant with conventional typing results, with no further editing being necessary. In addition, the amount of typing information, i.e., nucleotides and target genes analyzed, could be substantially increased by the combined use of genome sequencing and BIGSdb compared to conventional methods. In the near future, affordable and fast benchtop NGS machines like the PGM might enable reference laboratories to switch to genomic typing on a routine basis. This will reduce workloads and rapidly provide information for laboratory surveillance, outbreak investigation, assessment of vaccine preventability, and antibiotic resistance gene monitoring.
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Late repression of NF-κB activity by invasive but not non-invasive meningococcal isolates is required to display apoptosis of epithelial cells. PLoS Pathog 2011; 7:e1002403. [PMID: 22144896 PMCID: PMC3228807 DOI: 10.1371/journal.ppat.1002403] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 10/11/2011] [Indexed: 01/24/2023] Open
Abstract
Meningococcal invasive isolates of the ST-11 clonal complex are most frequently associated with disease and rarely found in carriers. Unlike carriage isolates, invasive isolates induce apoptosis in epithelial cells through the TNF-α signaling pathway. While invasive and non-invasive isolates are both able to trigger the TLR4/MyD88 pathway in lipooligosaccharide (LOS)-dependant manner, we show that only non-invasive isolates were able to induce sustained NF-κB activity in infected epithelial cells. ST-11 invasive isolates initially triggered a strong NF-κB activity in infected epithelial cells that was abolished after 9 h of infection and was associated with sustained activation of JNK, increased levels of membrane TNFR1, and induction of apoptosis. In contrast, infection with carriage isolates lead to prolonged activation of NF-κB that was associated with a transient activation of JNK increased TACE/ADAM17-mediated shedding of TNFR1 and protection against apoptosis. Our data provide insights to understand the meningococcal duality between invasiveness and asymptomatic carriage.
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Ibarz-Pavón AB, MacLennan J, Andrews NJ, Gray SJ, Urwin R, Clarke SC, Walker AM, Evans MR, Kroll JS, Neal KR, Ala'Aldeen D, Crook DW, Cann K, Harrison S, Cunningham R, Baxter D, Kaczmarski E, McCarthy ND, Jolley KA, Cameron JC, Stuart JM, Maiden MCJ. Changes in serogroup and genotype prevalence among carried meningococci in the United Kingdom during vaccine implementation. J Infect Dis 2011; 204:1046-53. [PMID: 21881120 PMCID: PMC3164428 DOI: 10.1093/infdis/jir466] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 05/13/2011] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Herd immunity is important in the effectiveness of conjugate polysaccharide vaccines against encapsulated bacteria. A large multicenter study investigated the effect of meningococcal serogroup C conjugate vaccine introduction on the meningococcal population. METHODS Carried meningococci in individuals aged 15-19 years attending education establishments were investigated before and for 2 years after vaccine introduction. Isolates were characterized by multilocus sequence typing, serogroup, and capsular region genotype and changes in phenotypes and genotypes assessed. RESULTS A total of 8462 meningococci were isolated from 47 765 participants (17.7%). Serogroup prevalence was similar over the 3 years, except for decreases of 80% for serogroup C and 40% for serogroup 29E. Clonal complexes were associated with particular serogroups and their relative proportions fluctuated, with 12 statistically significant changes (6 up, 6 down). The reduction of ST-11 complex serogroup C meningococci was probably due to vaccine introduction. Reasons for a decrease in serogroup 29E ST-254 meningococci (from 1.8% to 0.7%) and an increase in serogroup B ST-213 complex meningococci (from 6.7% to 10.6%) were less clear. CONCLUSIONS Natural fluctuations in carried meningococcal genotypes and phenotypes a can be affected by the use of conjugate vaccines, and not all of these changes are anticipatable in advance of vaccine introduction.
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Affiliation(s)
| | | | | | - Stephen J. Gray
- Meningococcal Reference Unit, Health Protection Agency, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary
| | | | - Stuart C. Clarke
- Division of Infection, Inflammation and Immunity, University of Southampton, School of Medicine, Southampton National Institute for Health Research Biomedical Research Unit in Respiratory Medicine, and Health Protection Agency, Southampton
| | | | - Meirion R. Evans
- Department of Primary Care and Public Health, Cardiff University
| | - J. Simon Kroll
- Imperial College School of Medicine, Norfolk Place, London
| | - Keith R. Neal
- University of Nottingham, Epidemiology and Public Health, Community Health Sciences, Queen's Medical Centre
| | - Dlawer Ala'Aldeen
- Division of Microbiology, School of Molecular Medicine, University Hospital, Nottingham
| | - Derrick W. Crook
- Nuffield Department of Clinical and Laboratory Sciences, John Radcliffe Hospital, Headley Way, University of Oxford
| | - Kathryn Cann
- Nuffield Department of Clinical and Laboratory Sciences, John Radcliffe Hospital, Headley Way, University of Oxford
| | | | | | - David Baxter
- Division of Epidemiology and Health Sciences, Medical School, The University of Manchester
| | - Edward Kaczmarski
- Meningococcal Reference Unit, Health Protection Agency, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary
| | | | | | | | - James M. Stuart
- School of Social and Community Medicine, University of Bristol, United Kingdom
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Distribution of serogroups and sequence types in disease-associated and carrier strains of Neisseria meningitidis isolated in China between 2003 and 2008. Epidemiol Infect 2011; 140:1296-303. [PMID: 21929839 DOI: 10.1017/s0950268811001865] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Given the unpredictability of Neisseria meningitidis outbreaks and the increased prevalence of serogroup C strains following the introduction of serogroup A-based vaccines, we conducted an analysis of serogroups and sequence types (STs) in disease-associated and carrier N. meningitidis isolates that have emerged in China since 2003. We used multilocus sequence-typing techniques to investigate 371 N. meningitidis strains isolated from patients with meningitis and healthy carriers. Two lineages were identified in serogroup A and C isolates, genotyped as the ST5 complex and ST4821 complex, respectively. Both clonal complexes were found throughout China, although ST4821 was more concentrated in the eastern region of the country. The ST5 complex has been persistent in China since the late 1980s and has since spread across the entire country. Isolates belonging to the ST4821 complex have been a dominant lineage since 2003.
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Pluciński MM, Starfield R, Almeida RPP. Inferring social network structure from bacterial sequence data. PLoS One 2011; 6:e22685. [PMID: 21829645 PMCID: PMC3148245 DOI: 10.1371/journal.pone.0022685] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 06/28/2011] [Indexed: 11/18/2022] Open
Abstract
Using DNA sequence data from pathogens to infer transmission networks has traditionally been done in the context of epidemics and outbreaks. Sequence data could analogously be applied to cases of ubiquitous commensal bacteria; however, instead of inferring chains of transmission to track the spread of a pathogen, sequence data for bacteria circulating in an endemic equilibrium could be used to infer information about host contact networks. Here, we show—using simulated data—that multilocus DNA sequence data, based on multilocus sequence typing schemes (MLST), from isolates of commensal bacteria can be used to infer both local and global properties of the contact networks of the populations being sampled. Specifically, for MLST data simulated from small-world networks, the small world parameter controlling the degree of structure in the contact network can robustly be estimated. Moreover, we show that pairwise distances in the network—degrees of separation—correlate with genetic distances between isolates, so that how far apart two individuals in the network are can be inferred from MLST analysis of their commensal bacteria. This result has important consequences, and we show an example from epidemiology: how this result could be used to test for infectious origins of diseases of unknown etiology.
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Affiliation(s)
- Mateusz M Pluciński
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California, United States of America.
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Seib KL, Pigozzi E, Muzzi A, Gawthorne JA, Delany I, Jennings MP, Rappuoli R. A novel epigenetic regulator associated with the hypervirulent
Neisseria meningitidis
clonal complex 41/44. FASEB J 2011; 25:3622-33. [DOI: 10.1096/fj.11-183590] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | | | | | - Jayde A. Gawthorne
- Institute for GlycomicsGriffith University Gold Coast Queensland Australia
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Genotypic and phenotypic modifications of Neisseria meningitidis after an accidental human passage. PLoS One 2011; 6:e17145. [PMID: 21386889 PMCID: PMC3046118 DOI: 10.1371/journal.pone.0017145] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 01/11/2011] [Indexed: 01/27/2023] Open
Abstract
A scientist in our laboratory was accidentally infected while working with Z5463, a Neisseria meningitidis serogroup A strain. She developed severe symptoms (fever, meningism, purpuric lesions) that fortunately evolved with antibiotic treatment to complete recovery. Pulse-field gel electrophoresis confirmed that the isolate obtained from the blood culture (Z5463BC) was identical to Z5463, more precisely to a fourth subculture of this strain used the week before the contamination (Z5463PI). In order to get some insights into genomic modifications that can occur in vivo, we sequenced these three isolates. All the strains contained a mutated mutS allele and therefore displayed an hypermutator phenotype, consistent with the high number of mutations (SNP, Single Nucleotide Polymorphism) detected in the three strains. By comparing the number of SNP in all three isolates and knowing the number of passages between Z5463 and Z5463PI, we concluded that around 25 bacterial divisions occurred in the human body. As expected, the in vivo passage is responsible for several modifications of phase variable genes. This genomic study has been completed by transcriptomic and phenotypic studies, showing that the blood strain used a different haemoglobin-linked iron receptor (HpuA/B) than the parental strains (HmbR). Different pilin variants were found after the in vivo passage, which expressed different properties of adhesion. Furthermore the deletion of one gene involved in LOS biosynthesis (lgtB) results in Z5463BC expressing a different LOS than the L9 immunotype of Z2491. The in vivo passage, despite the small numbers of divisions, permits the selection of numerous genomic modifications that may account for the high capacity of the strain to disseminate.
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Tauseef I, Harrison OB, Wooldridge KG, Feavers IM, Neal KR, Gray SJ, Kriz P, Turner DPJ, Ala'Aldeen DAA, Maiden MCJ, Bayliss CD, Shaw JG. Influence of the combination and phase variation status of the haemoglobin receptors HmbR and HpuAB on meningococcal virulence. MICROBIOLOGY-SGM 2011; 157:1446-1456. [PMID: 21310784 PMCID: PMC3352162 DOI: 10.1099/mic.0.046946-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Neisseria meningitidis can utilize haem, haemoglobin and haemoglobin–haptoglobin complexes as sources of iron via two TonB-dependent phase variable haemoglobin receptors, HmbR and HpuAB. HmbR is over-represented in disease isolates, suggesting a link between haemoglobin acquisition and meningococcal disease. This study compared the distribution of HpuAB and phase variation (PV) status of both receptors in disease and carriage isolates. Meningococcal disease (n = 214) and carriage (n = 305) isolates representative of multiple clonal complexes (CCs) were investigated for the distribution, polyG tract lengths and ON/OFF status of both haemoglobin receptors, and for the deletion mechanism for HpuAB. Strains with both receptors or only hmbR were present at similar frequencies among meningococcal disease isolates as compared with carriage isolates. However, >90 % of isolates from the three CCs CC5, CC8 and CC11 with the highest disease to carriage ratios contained both receptors. Strains with an hpuAB-only phenotype were under-represented among disease isolates, suggesting selection against this receptor during systemic disease, possibly due to the receptor having a high level of immunogenicity or being inefficient in acquisition of iron during systemic spread. Absence of hpuAB resulted from either complete deletion or replacement by an insertion element. In an examination of PV status, one or both receptors were found in an ON state in 91 % of disease and 71 % of carriage isolates. We suggest that expression of a haemoglobin receptor, either HmbR or HpuAB, is of major importance for systemic spread of meningococci, and that the presence of both receptors contributes to virulence in some strains.
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Affiliation(s)
- Isfahan Tauseef
- Department of Genetics, University of Leicester, Leicester LE1 7RH, UK
| | - Odile B Harrison
- The Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3SY, UK
| | - Karl G Wooldridge
- Molecular Bacteriology and Immunology Group, University of Nottingham, Nottingham, UK
| | - Ian M Feavers
- National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Hertfordshire EN6 3QG, UK
| | - Keith R Neal
- School of Community Health Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Gray
- Health Protection Agency, Meningococcal Reference Unit, Manchester Royal Infirmary, Manchester M13 9WL, UK
| | - Paula Kriz
- National Reference Laboratory for Meningococcal Infections, National Institute of Public Health, Prague, Czech Republic
| | - David P J Turner
- Molecular Bacteriology and Immunology Group, University of Nottingham, Nottingham, UK
| | - Dlawer A A Ala'Aldeen
- Molecular Bacteriology and Immunology Group, University of Nottingham, Nottingham, UK
| | - Martin C J Maiden
- The Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3SY, UK
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Christensen H, May M, Bowen L, Hickman M, Trotter CL. Meningococcal carriage by age: a systematic review and meta-analysis. THE LANCET. INFECTIOUS DISEASES 2010; 10:853-61. [PMID: 21075057 DOI: 10.1016/s1473-3099(10)70251-6] [Citation(s) in RCA: 432] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Aspholm M, Aas FE, Harrison OB, Quinn D, Vik Å, Viburiene R, Tønjum T, Moir J, Maiden MCJ, Koomey M. Structural alterations in a component of cytochrome c oxidase and molecular evolution of pathogenic Neisseria in humans. PLoS Pathog 2010; 6:e1001055. [PMID: 20808844 PMCID: PMC2924362 DOI: 10.1371/journal.ppat.1001055] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 07/21/2010] [Indexed: 12/26/2022] Open
Abstract
Three closely related bacterial species within the genus Neisseria are of importance to human disease and health. Neisseria meningitidis is a major cause of meningitis, while Neisseria gonorrhoeae is the agent of the sexually transmitted disease gonorrhea and Neisseria lactamica is a common, harmless commensal of children. Comparative genomics have yet to yield clear insights into which factors dictate the unique host-parasite relationships exhibited by each since, as a group, they display remarkable conservation at the levels of nucleotide sequence, gene content and synteny. Here, we discovered two rare alterations in the gene encoding the CcoP protein component of cytochrome cbb3 oxidase that are phylogenetically informative. One is a single nucleotide polymorphism resulting in CcoP truncation that acts as a molecular signature for the species N. meningitidis. We go on to show that the ancestral ccoP gene arose by a unique gene duplication and fusion event and is specifically and completely distributed within species of the genus Neisseria. Surprisingly, we found that strains engineered to express either of the two CcoP forms conditionally differed in their capacity to support nitrite-dependent, microaerobic growth mediated by NirK, a nitrite reductase. Thus, we propose that changes in CcoP domain architecture and ensuing alterations in function are key traits in successive, adaptive radiations within these metapopulations. These findings provide a dramatic example of how rare changes in core metabolic proteins can be connected to significant macroevolutionary shifts. They also show how evolutionary change at the molecular level can be linked to metabolic innovation and its reversal as well as demonstrating how genotype can be used to infer alterations of the fitness landscape within a single host. The closely related bacterial species N. meningitidis, N. gonorrhoeae and N. lactamica exclusively colonise mucosal surfaces in humans. While N. gonorrhoeae leads to gonorrhea, the other two species persist mainly in their host in the absence of disease. N. meningitidis does occasionally cause severe, life threatening illness, however. Little is known about the factors and elements that dictate the unique human interactions exhibited by each species. Moreover, the evolutionary relationships between these species are poorly characterized. Here, we describe two successive alterations in a single gene that can be linked first to all species within the genus Neisseria and then the species N. meningitidis. We also show these signature alterations have phenotypic consequences by affecting core respiratory metabolic processes. These findings have significant implications for the evolution of related bacterial species within a single host and provide a novel perspective on the episodic and reversible nature of innovative adaptation.
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Affiliation(s)
- Marina Aspholm
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
| | - Finn Erik Aas
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
| | | | - Diana Quinn
- Department of Biology (Area 10), University of York, Heslington, York, United Kingdom
| | - Åshild Vik
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
| | - Raimonda Viburiene
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
| | - Tone Tønjum
- Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
- Institute of Microbiology, University of Oslo, Oslo, Norway
| | - James Moir
- Department of Biology (Area 10), University of York, Heslington, York, United Kingdom
| | | | - Michael Koomey
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Biology and Neuroscience, University of Oslo, Oslo, Norway
- * E-mail:
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Comparative genome biology of a serogroup B carriage and disease strain supports a polygenic nature of meningococcal virulence. J Bacteriol 2010; 192:5363-77. [PMID: 20709895 DOI: 10.1128/jb.00883-10] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neisseria meningitidis serogroup B strains are responsible for most meningococcal cases in the industrialized countries, and strains belonging to the clonal complex ST-41/44 are among the most prevalent serogroup B strains in carriage and disease. Here, we report the first genome and transcriptome comparison of a serogroup B carriage strain from the clonal complex ST-41/44 to the serogroup B disease strain MC58 from the clonal complex ST-32. Both genomes are highly colinear, with only three major genome rearrangements that are associated with the integration of mobile genetic elements. They further differ in about 10% of their gene content, with the highest variability in gene presence as well as gene sequence found for proteins involved in host cell interactions, including Opc, NadA, TonB-dependent receptors, RTX toxin, and two-partner secretion system proteins. Whereas housekeeping genes coding for metabolic functions were highly conserved, there were considerable differences in their expression pattern upon adhesion to human nasopharyngeal cells between both strains, including differences in energy metabolism and stress response. In line with these genomic and transcriptomic differences, both strains also showed marked differences in their in vitro infectivity and in serum resistance. Taken together, these data support the concept of a polygenic nature of meningococcal virulence comprising differences in the repertoire of adhesins as well as in the regulation of metabolic genes and suggest a prominent role for immune selection and genetic drift in shaping the meningococcal genome.
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The elusive meningococcal meningitis serogroup: a systematic review of serogroup B epidemiology. BMC Infect Dis 2010; 10:175. [PMID: 20565757 PMCID: PMC2894839 DOI: 10.1186/1471-2334-10-175] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 06/17/2010] [Indexed: 11/23/2022] Open
Abstract
Background Invasive meningococcal disease (IMD), is a widely distributed, complex human disease affecting all age categories. The causative agent, Neisseria meningitidis, is spread through aerosol respiratory droplets. 13 different serogroups have been identified, each with varying epidemiological features including prevalence, virulence, immunogenicity, geographical and temporal distribution. Although preventative measures are available for several of the serogroups, meningococcal disease caused by serogroup B is of particular interest due to the challenge it presents concerning vaccine development. Methods A systematic review of peer reviewed studies and reports, the collection of data from national and international health resources, along with the analysis of the Multi Locus Sequence Typing database was carried out aimed at collecting information concerning serogroup B IMD and the epidemiology attached to it. Results A continuous output of related and novel STs occurring worldwide in terms of the hypervirulent clonal complexes was observed both in published studies and the MLST database in this case using the eburst software, which highlights the genetically diverse nature of serogroup B strains. Conclusions With the recent dominance of serogroup B IMD seen in many countries, along with the presence of antibiotic resistance, vaccine development needs to target areas of the bacterium which tackle this widespread and heterogeneous aspect of meningococcal meningitis disease.
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Biofilm formation by the human pathogen Neisseria meningitidis. Med Microbiol Immunol 2010; 199:173-83. [PMID: 20376486 DOI: 10.1007/s00430-010-0149-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Indexed: 10/19/2022]
Abstract
The past decade has seen an increasing interest in biofilm formation by Neisseria meningitidis, a human facultative pathogen causing life-threatening childhood disease commencing from asymptomatic nasopharyngeal colonization. Studying the biology of in vitro biofilm formation improves the understanding of inter-bacterial processes in asymptomatic carriage, of bacterial aggregate formation on host cells, and of meningococcal population biology. This paper reviews publications referring to meningococcal biofilm formation with an emphasis on the role of motility and of extracellular DNA. The theory of sub-dividing the meningococcal population in settler and spreader lineages is discussed, which provides a mechanistic framework for the assumed balance of colonization efficacy and transmission frequency.
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Buckee CO, Gupta S, Kriz P, Maiden MCJ, Jolley KA. Long-term evolution of antigen repertoires among carried meningococci. Proc Biol Sci 2010; 277:1635-41. [PMID: 20129981 PMCID: PMC2871849 DOI: 10.1098/rspb.2009.2033] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Most studies of bacterial pathogen populations have been based on isolates collected from individuals with disease, or their contacts, over short time periods. For commensal organisms that occasionally cause disease, such as Neisseria meningitidis, however, the analysis of isolates from long-term asymptomatic carriage is necessary to elucidate their evolution and population structure. Here, we use mathematical models to analyse the structuring and dynamics of three vaccine-candidate antigens among carried meningococcal isolates collected over nearly 30 years in the Czech Republic. The data indicate that stable combinations of antigenic alleles were maintained over this time period despite evidence for high rates of recombination, consistent with theoretical models in which strong immune selection can maintain non-overlapping combinations of antigenic determinants in the presence of recombination. We contrast this antigenic structure with the overlapping but relatively stable combinations of the housekeeping genes observed among the same isolates, and use a novel network approach to visualize these relationships.
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Pollock FJ, Wilson B, Johnson WR, Morris PJ, Willis BL, Bourne DG. Phylogeny of the coral pathogen Vibrio coralliilyticus. ENVIRONMENTAL MICROBIOLOGY REPORTS 2010; 2:172-178. [PMID: 23766013 DOI: 10.1111/j.1758-2229.2009.00131.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A phenotypic and phylogenetic comparison of geographically disparate isolates of the coral pathogen Vibrio coralliilyticus was conducted to determine whether the bacterium exists as a single cosmopolitan clonal population, which might indicate rapid spread of a pandemic strain, or is grouped into endemic and genotypically distinct strains. All strains included in this study displayed similar phenotypic characteristics to those of the typed V. coralliilyticus strain LMG 20984(T) . Five phylogenetic marker genes (16S, rpoA, recA, pyrH and dnaJ) frequently used for discriminating closely related Vibrio species and a zinc-metalloprotease gene (vcpA) linked to pathogenicity were sequenced in 13 V. coralliilyticus isolates collected from corals, bivalves, and their surrounding seawater in the Red and Caribbean Seas, and Indian, Pacific and Atlantic Oceans. A high level of genetic polymorphism was observed with all isolates possessing unique genotypes at all six genetic loci examined. No consistent lineage structure was observed within the marker genes and homologous recombination was detected in the 16S and vcpA genes, suggesting that V. coralliilyticus does not possess a highly clonal population structure. Interestingly, two geographically distinct (Caribbean/south-Atlantic and Indo-Pacific/north-Atlantic) and highly divergent clades were detected within the zinc-metalloprotease gene, but it is not known if these clades correspond to phenotypic differences in virulence. These findings stress the need for a multi-locus approach for inferring V. coralliilyticus phylogeny and indicate that populations of this bacterium are likely an endemic component of coral reef ecosystems globally.
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Affiliation(s)
- F Joseph Pollock
- Australian Institute of Marine Science, PMB 3, Townsville 4810, Australia. College of Charleston, Charleston, SC 29412, USA. Hollings Marine Laboratory, Charleston, SC 29412, USA. ARC Centre of Excellence for Coral Reef Studies, School of Marine and Tropical Biology, James Cook University, Townsville 4811, Australia
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Clonal distribution of disease-associated and healthy carrier isolates of Neisseria meningitidis between 1983 and 2005 in Cuba. J Clin Microbiol 2009; 48:802-10. [PMID: 20042619 DOI: 10.1128/jcm.01653-09] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In response to epidemic levels of serogroup B meningococcal disease in Cuba during the 1980s, the VA-MENGOC-BC vaccine was developed and introduced into the National Infant Immunization Program in 1991. Since then the incidence of meningococcal disease in Cuba has returned to the low levels recorded before the epidemic. A total of 420 Neisseria meningitidis strains collected between 1983 and 2005 in Cuba were analyzed by multilocus sequence typing (MLST). The set of strains comprised 167 isolated from disease cases and 253 obtained from healthy carriers. By MLST analysis, 63 sequence types (STs) were identified, and 32 of these were reported to be a new ST. The Cuban isolates were associated with 12 clonal complexes; and the most common were ST-32 (246 isolates), ST-53 (86 isolates), and ST-41/44 (36 isolates). This study also showed that the application of VA-MENGOC-BC, the Cuban serogroup B and C vaccine, reduced the frequency and diversity of hypervirulent clonal complexes ST-32 (vaccine serogroup B type-strain) and ST-41/44 and also affected other lineages. Lineages ST-8 and ST-11 were no longer found during the postvaccination period. The vaccine also affected the genetic composition of the carrier-associated meningococcal isolates. The number of carrier isolates belonging to hypervirulent lineages decreased significantly after vaccination, and ST-53, a sequence type common in carriers, became the predominant ST.
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Linking questions to practices in the study of microbial pathogens: Sampling bias and typing methods. INFECTION GENETICS AND EVOLUTION 2009; 9:1418-23. [DOI: 10.1016/j.meegid.2009.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2009] [Revised: 08/21/2009] [Accepted: 08/21/2009] [Indexed: 01/10/2023]
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Harrison OB, Evans NJ, Blair JM, Grimes HS, Tinsley CR, Nassif X, Kriz P, Ure R, Gray SJ, Derrick JP, Maiden MCJ, Feavers IM. Epidemiological evidence for the role of the hemoglobin receptor, hmbR, in meningococcal virulence. J Infect Dis 2009; 200:94-8. [PMID: 19476432 DOI: 10.1086/599377] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The distribution of the hemoglobin receptor gene (hmbR) was investigated among disease and carriage Neisseria meningitidis isolates, revealing that the gene was detected at a significantly higher frequency among disease isolates than among carriage isolates. In isolates without hmbR, the locus was occupied by the cassettes exl2 or exl3 or by a "pseudo hmbR" gene, designated exl4. The hmbR locus exhibited characteristics of a pathogenicity island in published genomes of N. meningitidis, Neisseria gonorrhoeae, and Neisseria lactamica sequence type-640. These data are consistent with a role for the hmbR gene in meningococcal disease.
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Affiliation(s)
- Odile B Harrison
- Department of Zoology, University of Oxford, Oxford, United Kingdom
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Tang J, Hanage WP, Fraser C, Corander J. Identifying currents in the gene pool for bacterial populations using an integrative approach. PLoS Comput Biol 2009; 5:e1000455. [PMID: 19662158 PMCID: PMC2713424 DOI: 10.1371/journal.pcbi.1000455] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 07/01/2009] [Indexed: 11/18/2022] Open
Abstract
The evolution of bacterial populations has recently become considerably better understood due to large-scale sequencing of population samples. It has become clear that DNA sequences from a multitude of genes, as well as a broad sample coverage of a target population, are needed to obtain a relatively unbiased view of its genetic structure and the patterns of ancestry connected to the strains. However, the traditional statistical methods for evolutionary inference, such as phylogenetic analysis, are associated with several difficulties under such an extensive sampling scenario, in particular when a considerable amount of recombination is anticipated to have taken place. To meet the needs of large-scale analyses of population structure for bacteria, we introduce here several statistical tools for the detection and representation of recombination between populations. Also, we introduce a model-based description of the shape of a population in sequence space, in terms of its molecular variability and affinity towards other populations. Extensive real data from the genus Neisseria are utilized to demonstrate the potential of an approach where these population genetic tools are combined with an phylogenetic analysis. The statistical tools introduced here are freely available in BAPS 5.2 software, which can be downloaded from http://web.abo.fi/fak/mnf/mate/jc/software/baps.html. The study of bacterial population biology is complicated by the fact that, although bacteria are largely asexual, they can also exchange genetic materials through homologous recombination. Unlike eukaryotes, recombination in bacteria is not an obligatory process. Furthermore, the recombination mechanisms are subject to many biological and ecological factors that can vary even within different populations of the same species. Although increasing evidence for homologous recombination has been found in many bacterial species, determining the frequency of recombination and understanding the influence that it exerts upon the evolution of bacterial populations remains a challenging work. In this article, we provide a dynamic picture of recombination within and between closely related bacteria species. Through an integration of several Bayesian statistical models, our method highlights the importance of a quantitative estimation of recombination. Our analyses of a challenging multi-locus sequence typing (MLST) database demonstrate that combined analyses using both traditional phylogenetic methods, explorative MLST tools and Bayesian population genetic models can together yield interesting biological insights that cannot easily be reached by any of the approaches alone.
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Affiliation(s)
- Jing Tang
- Department of Mathematics and Statistics, University of Helsinki, Helsinki, Finland.
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Didelot X, Urwin R, Maiden MCJ, Falush D. Genealogical typing of Neisseria meningitidis. MICROBIOLOGY-SGM 2009; 155:3176-3186. [PMID: 19643763 PMCID: PMC2762044 DOI: 10.1099/mic.0.031534-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Despite the increasing popularity of multilocus sequence typing (MLST), the most appropriate method for characterizing bacterial variation and facilitating epidemiological investigations remains a matter of debate. Here, we propose that different typing schemes should be compared on the basis of their power to infer clonal relationships and investigate the utility of sequence data for genealogical reconstruction by exploiting new statistical tools and data from 20 housekeeping loci for 93 isolates of the bacterial pathogen Neisseria meningitidis. Our analysis demonstrated that all but one of the hyperinvasive isolates established by multilocus enzyme electrophoresis and MLST were grouped into one of six genealogical lineages, each of which contained substantial variation. Due to the confounding effect of recombination, evolutionary relationships among these lineages remained unclear, even using 20 loci. Analyses of the seven loci in the standard MLST scheme using the same methods reproduced this classification, but were unable to support finer inferences concerning the relationships between the members within each complex.
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Affiliation(s)
| | - Rachel Urwin
- Department of Biology, Pennsylvania State University, USA
| | | | - Daniel Falush
- Environmental Research Institute, University College Cork, Ireland
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Fan J, Shu M, Zhang G, Zhou W, Jiang Y, Zhu Y, Chen G, Peacock SJ, Wan C, Pan W, Feil EJ. Biogeography and virulence of Staphylococcus aureus. PLoS One 2009; 4:e6216. [PMID: 19593449 PMCID: PMC2705676 DOI: 10.1371/journal.pone.0006216] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Accepted: 06/06/2009] [Indexed: 01/23/2023] Open
Abstract
Background Staphylococcus aureus is commonly carried asymptomatically in the human anterior nares and occasionally enters the bloodstream to cause invasive disease. Much of the global diversity of S. aureus remains uncharacterised, and is not clear how disease propensity varies between strains, and between host populations. Methodology We compared 147 isolates recovered from five kindergartens in Chengdu, China, with 51 isolates contemporaneously recovered from cases of pediatric infection from the main hospital serving this community. The samples were characterised by MLST, the presence/absence of PVL, and antibiotic resistance profiling. Principal Findings Genotype frequencies within individual kindergartens differ, but the sample recovered from cases of disease shows a general enrichment of certain MLST genotypes and PVL positive isolates. Genotypes under-represented in the disease sample tend to correspond to a single sequence cluster, and this cluster is more common in China than in other parts of the world. Conclusions/Significance Virulence propensity likely reflects a synergy between variation in the core genome (MLST) and accessory genome (PVL). By combining evidence form biogeography and virulence we demonstrate the existence of a “native” clade in West China which has lowered virulence, possibility due to acquired host immunity.
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Affiliation(s)
- Juan Fan
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
| | - Min Shu
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
| | - Ge Zhang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
| | - Wei Zhou
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
| | - Yongmei Jiang
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
| | - Yu Zhu
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
| | - Guihua Chen
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
| | - Sharon J. Peacock
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Chaomin Wan
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, the People's Republic of China
- * E-mail: (CW); (WP); (EJF)
| | - Wubin Pan
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, the People's Republic of China
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
- Crown Bioscience, Inc. (Beijing), Light Muller Building, ChangPing Science Park, Beijing, the People's Republic of China
- * E-mail: (CW); (WP); (EJF)
| | - Edward J. Feil
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
- * E-mail: (CW); (WP); (EJF)
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Abstract
As reviewed in this paper, meningococcal disease epidemiology varies substantially by geographic area and time. The disease can occur as sporadic cases, outbreaks, and large epidemics. Surveillance is crucial for understanding meningococcal disease epidemiology, as well as the need for and impact of vaccination. Despite limited data from some regions of the world and constant change, current meningococcal disease epidemiology can be summarized by region. By far the highest incidence of meningococcal disease occurs in the meningitis belt of sub-Saharan Africa. During epidemics, the incidence can approach 1000 per 100,000, or 1% of the population. Serogroup A has been the most important serogroup in this region. However, serogroup C disease has also occurred, as has serogroup X disease and, most recently, serogroup W-135 disease. In the Americas, the reported incidence of disease, in the range of 0.3-4 cases per 100,000 population, is much lower than in the meningitis belt. In addition, in some countries such as the United States, the incidence is at an historical low. The bulk of the disease in the Americas is caused by serogroups C and B, although serogroup Y causes a substantial proportion of infections in some countries and W-135 is becoming increasingly problematic as well. The majority of meningococcal disease in European countries, which ranges in incidence from 0.2 to 14 cases per 100,000, is caused by serogroup B strains, particularly in countries that have introduced serogroup C meningococcal conjugate vaccines. Serogroup B also predominates in Australia and New Zealand, in Australia because of the control of serogroup C disease through vaccination and in New Zealand because of a serogroup B epidemic. Based on limited data, most disease in Asia is caused by serogroup A and C strains. Although this review summarizes the current status of meningococcal disease epidemiology, the dynamic nature of this disease requires ongoing surveillance both to provide data for vaccine formulation and vaccine policy and to monitor the impact of vaccines following introduction.
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