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Mattos-Graner RO, Klein MI, Alves LA. The complement system as a key modulator of the oral microbiome in health and disease. Crit Rev Microbiol 2024; 50:138-167. [PMID: 36622855 DOI: 10.1080/1040841x.2022.2163614] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 01/10/2023]
Abstract
In this review, we address the interplay between the complement system and host microbiomes in health and disease, focussing on oral bacteria known to contribute to homeostasis or to promote dysbiosis associated with dental caries and periodontal diseases. Host proteins modulating complement activities in the oral environment and expression profiles of complement proteins in oral tissues were described. In addition, we highlight a sub-set of bacterial proteins involved in complement evasion and/or dysregulation previously characterized in pathogenic species (or strains), but further conserved among prototypical commensal species of the oral microbiome. Potential roles of these proteins in host-microbiome homeostasis and in the emergence of commensal strain lineages with increased virulence were also addressed. Finally, we provide examples of how commensal bacteria might exploit the complement system in competitive or cooperative interactions within the complex microbial communities of oral biofilms. These issues highlight the need for studies investigating the effects of the complement system on bacterial behaviour and competitiveness during their complex interactions within oral and extra-oral host sites.
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Affiliation(s)
- Renata O Mattos-Graner
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas (UNICAMP), Sao Paulo, Brazil
| | - Marlise I Klein
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas (UNICAMP), Sao Paulo, Brazil
| | - Lívia Araújo Alves
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas (UNICAMP), Sao Paulo, Brazil
- School of Dentistry, Cruzeiro do Sul University (UNICSUL), Sao Paulo, Brazil
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2
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Milly TA, Renshaw CP, Tal-Gan Y. Developing multispecies quorum-sensing modulators based on the Streptococcus mitis competence-stimulating peptide. J Biol Chem 2023; 299:105448. [PMID: 37951305 PMCID: PMC10714334 DOI: 10.1016/j.jbc.2023.105448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 10/26/2023] [Accepted: 10/30/2023] [Indexed: 11/13/2023] Open
Abstract
Bacteria utilize quorum sensing (QS) to coordinate many group behaviors. As such, QS has attracted significant attention as a potential mean to attenuate bacterial infectivity without introducing selective pressure for resistance development. Streptococcus mitis, a human commensal, acts as a genetic diversity reservoir for Streptococcus pneumoniae, a prevalent human pathogen. S. mitis possesses a typical comABCDE competence regulon QS circuitry; however, the competence-stimulating peptide (CSP) responsible for QS activation and the regulatory role of the competence regulon QS circuitry in S. mitis are yet to be explored. We set out to delineate the competence regulon QS circuitry in S. mitis, including confirming the identity of the native CSP signal, evaluating the molecular mechanism that governs CSP interactions with histidine kinase receptor ComD leading to ComD activation, and defining the regulatory roles of the competence regulon QS circuitry in initiating various S. mitis phenotypes. Our analysis revealed important structure-activity relationship insights of the CSP signal and facilitated the development of novel CSP-based QS modulators. Our analysis also revealed the involvement of the competence regulon in modulating competence development and biofilm formation. Furthermore, our analysis revealed that the native S. mitis CSP signal can modulate QS response in S. pneumoniae. Capitalizing on this crosstalk, we developed a multispecies QS modulator that activates both the pneumococcus ComD receptors and the S. mitis ComD-2 receptor with high potencies. The novel scaffolds identified herein can be utilized to evaluate the effects temporal QS modulation has on S. mitis as it inhabits its natural niche.
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Affiliation(s)
- Tahmina A Milly
- Department of Chemistry, University of Nevada, Reno, Reno, Nevada, USA
| | - Clay P Renshaw
- Department of Chemistry, University of Nevada, Reno, Reno, Nevada, USA
| | - Yftah Tal-Gan
- Department of Chemistry, University of Nevada, Reno, Reno, Nevada, USA.
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3
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Kuryłek A, Stasiak M, Kern-Zdanowicz I. Virulence factors of Streptococcus anginosus - a molecular perspective. Front Microbiol 2022; 13:1025136. [PMID: 36386673 PMCID: PMC9643698 DOI: 10.3389/fmicb.2022.1025136] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 10/10/2022] [Indexed: 07/21/2023] Open
Abstract
Streptococcus anginosus together with S. constellatus and S. intermedius constitute the Streptococcus anginosus group (SAG), until recently considered to be benign commensals of the human mucosa isolated predominantly from oral cavity, but also from upper respiratory, intestinal, and urogenital tracts. For years the virulence potential of SAG was underestimated, mainly due to complications in correct species identification and their assignment to the physiological microbiota. Still, SAG representatives have been associated with purulent infections at oral and non-oral sites resulting in abscesses formation and empyema. Also, life threatening blood infections caused by SAG have been reported. However, the understanding of SAG as potential pathogen is only fragmentary, albeit certain aspects of SAG infection seem sufficiently well described to deserve a systematic overview. In this review we summarize the current state of knowledge of the S. anginosus pathogenicity factors and their mechanisms of action.
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4
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Jakubovics NS, Goodman SD, Mashburn-Warren L, Stafford GP, Cieplik F. The dental plaque biofilm matrix. Periodontol 2000 2021; 86:32-56. [PMID: 33690911 PMCID: PMC9413593 DOI: 10.1111/prd.12361] [Citation(s) in RCA: 132] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
| | - Steven D Goodman
- Center for Microbial Pathogenesis, The Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Lauren Mashburn-Warren
- Center for Microbial Pathogenesis, The Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Graham P Stafford
- Integrated Biosciences, School of Clinical Dentistry, University of Sheffield, Sheffield, UK
| | - Fabian Cieplik
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Regensburg, Germany
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5
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Potential Risk of Spreading Resistance Genes within Extracellular-DNA-Dependent Biofilms of Streptococcus mutans in Response to Cell Envelope Stress Induced by Sub-MICs of Bacitracin. Appl Environ Microbiol 2020; 86:AEM.00770-20. [PMID: 32532873 DOI: 10.1128/aem.00770-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 06/08/2020] [Indexed: 02/07/2023] Open
Abstract
Antibiotics are used to treat or prevent some types of bacterial infection. The inappropriate use of antibiotics unnecessarily promotes antibiotic resistance and increases resistant bacteria, and controlling these bacteria is difficult. While the emergence of drug-resistant bacteria is a serious problem, the behavior of drug-resistant bacteria is not fully understood. In this study, we investigated the behavior of Streptococcus mutans, a major etiological agent of dental caries that is resistant to bacitracin, which is a cell wall-targeting antibiotic, and focused on biofilm formation in the presence of bacitracin. S. mutans UA159 most strongly induced extracellular DNA (eDNA)-dependent biofilm formation in the presence of bacitracin at 1/8× MIC. The ΔmbrC and ΔmbrD mutant strains, which lack bacitracin resistance, also formed biofilms in the presence of bacitracin at 1/2× MIC. This difference between the wild type and the mutants was caused by the induction of atlA expression in the mid-log phase. We also revealed that certain rgp genes involved in the synthesis of rhamnose-glucose polysaccharide related to cell wall synthesis were downregulated by bacitracin. In addition, glucosyltransferase-I was also involved in eDNA-dependent biofilm formation. The biofilm led to increased transformation efficiencies and promoted horizontal gene transfer. Biofilms were also induced by ampicillin and vancomycin, antibiotics targeting cell wall synthesis, suggesting that cell envelope stress triggers biofilm formation. Therefore, the expression of the atlA and rgp genes is regulated by S. mutans, which forms eDNA-dependent biofilms, promoting horizontal gene transfer in response to cell envelope stress induced by sub-MICs of antibiotics.IMPORTANCE Antibiotics have been reported to induce biofilm formation in many bacteria at subinhibitory concentrations. Accordingly, it is conceivable that the MIC against drug-sensitive bacteria may promote biofilm formation of resistant bacteria. Since drug-resistant bacteria have spread, it is important to understand the behavior of resistant bacteria. Streptococcus mutans is bacitracin resistant, and the 1/8× MIC of bacitracin, which is a cell wall-targeted antibiotic, induced eDNA-dependent biofilm formation. The ΔmbrC and ΔmbrD strains, which are not resistant to bacitracin, also formed biofilms in the presence of bacitracin at 1/2× MIC, and biofilms of both the wild type and mutants promoted horizontal gene transfer. Another cell wall-targeted antibiotic, vancomycin, showed effects on biofilms and gene transfer similar to those of bacitracin. Thus, treatment with cell wall-targeted antibiotics may promote the spread of drug-resistant genes in biofilms. Therefore, the behavior of resistant bacteria in the presence of antibiotics at sub-MICs should be investigated when using antibiotics.
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6
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Marshall H, Aguayo S, Kilian M, Petersen F, Bozec L, Brown J. In Vivo Relationship between the Nano-Biomechanical Properties of Streptococcal Polysaccharide Capsules and Virulence Phenotype. ACS NANO 2020; 14:1070-1083. [PMID: 31854972 DOI: 10.1021/acsnano.9b08631] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In common with many bacterial pathogens, Streptococcus pneumoniae has a polysaccharide capsule which facilitates immune evasion and determines virulence. Recent data have shown that the closely related Streptococcus mitis also expresses polysaccharide capsules including those with an identical chemical structure to S. pneumoniae capsular serotypes. We utilized atomic force microscopy (AFM) techniques to investigate the biophysical properties of S. mitis and S. pneumoniae strains expressing the same capsular serotypes that might relate to differences in virulence potential. When comparing S. mitis and S. pneumoniae strains with identical capsule serotypes, S. mitis strains were susceptible to neutrophil killing, and electron microscopy and AFM demonstrated significant morphological differences. Force-volume mapping using AFM showed distinct force-curve profiles for the center and edge areas of encapsulated streptococcal strains. This "edge effect" was not observed in unencapsulated bacteria and therefore was a direct representation of the mechanical properties of the bacterial capsule. When two strains of S. mitis and S. pneumoniae expressed an identical capsular serotype, they presented similar biomechanical characteristics. This infers a potential relationship between capsule biochemistry and nanomechanics, independent of bacterial strain. Overall, this study demonstrates that it is possible to investigate reproducibly the mechanistic, structural, and mechanical properties of both the capsule and the body of individual living bacterial cells and relate the data to virulence phenotypes. We have demonstrated that using nanomechanics to investigate individual bacterial cells we can now begin to identify the surface properties bacterial pathogens require to avoid host-mediated immunity.
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Affiliation(s)
- Helina Marshall
- Centre for Inflammation and Tissue Repair, Department of Medicine, Royal Free and University College Medical School , Rayne Institute , London WC1E 6JF , United Kingdom
- School of Biological Sciences , Queen's University Belfast , Belfast BT7 1NN , United Kingdom
| | - Sebastian Aguayo
- Biomaterials and Tissue Engineering, Eastman Dental Institute , University College London , London WC1E 6BT , United Kingdom
- School of Dentistry, Faculty of Medicine , Pontificia Universidad Catolica de Chile , Santiago , Chile
| | - Mogens Kilian
- Department of Biomedicine, Faculty of Health , Aarhus University , Aarhus 8000 , Denmark
| | - Fernanda Petersen
- Faculty of Dentistry, Institute of Oral Biology , University of Oslo , Oslo 0315 , Norway
| | - Laurent Bozec
- Biomaterials and Tissue Engineering, Eastman Dental Institute , University College London , London WC1E 6BT , United Kingdom
- Faculty of Dentistry , University of Toronto , Toronto , Ontario M5G 1G6 , Canada
| | - Jeremy Brown
- Centre for Inflammation and Tissue Repair, Department of Medicine, Royal Free and University College Medical School , Rayne Institute , London WC1E 6JF , United Kingdom
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7
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Streptococcus mitis Expressing Pneumococcal Serotype 1 Capsule. Sci Rep 2018; 8:17959. [PMID: 30568178 PMCID: PMC6299277 DOI: 10.1038/s41598-018-35921-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 11/08/2018] [Indexed: 01/22/2023] Open
Abstract
Streptococcus pneumoniae's polysaccharide capsule is an important virulence factor; vaccine-induced immunity to specific capsular polysaccharide effectively prevents disease. Serotype 1 S. pneumoniae is rarely found in healthy persons, but is highly invasive and a common cause of meningitis outbreaks and invasive disease outside of the United States. Here we show that genes for polysaccharide capsule similar to those expressed by pneumococci were commonly detected by polymerase chain reaction among upper respiratory tract samples from older US adults not carrying pneumococci. Serotype 1-specific genes were predominantly detected. In five oropharyngeal samples tested, serotype 1 gene belonging to S. mitis expressed capsules immunologically indistinct from pneumococcal capsules. Whole genome sequencing revealed three distinct S. mitis clones, each representing a cps1 operon highly similar to the pneumococcal cps1 reference operon. These findings raise important questions about the contribution of commensal streptococci to natural immunity against pneumococci, a leading cause of mortality worldwide.
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8
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Couvigny B, Kulakauskas S, Pons N, Quinquis B, Abraham AL, Meylheuc T, Delorme C, Renault P, Briandet R, Lapaque N, Guédon E. Identification of New Factors Modulating Adhesion Abilities of the Pioneer Commensal Bacterium Streptococcus salivarius. Front Microbiol 2018. [PMID: 29515553 PMCID: PMC5826255 DOI: 10.3389/fmicb.2018.00273] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Biofilm formation is crucial for bacterial community development and host colonization by Streptococcus salivarius, a pioneer colonizer and commensal bacterium of the human gastrointestinal tract. This ability to form biofilms depends on bacterial adhesion to host surfaces, and on the intercellular aggregation contributing to biofilm cohesiveness. Many S. salivarius isolates auto-aggregate, an adhesion process mediated by cell surface proteins. To gain an insight into the genetic factors of S. salivarius that dictate host adhesion and biofilm formation, we developed a screening method, based on the differential sedimentation of bacteria in semi-liquid conditions according to their auto-aggregation capacity, which allowed us to identify twelve mutations affecting this auto-aggregation phenotype. Mutations targeted genes encoding (i) extracellular components, including the CshA surface-exposed protein, the extracellular BglB glucan-binding protein, the GtfE, GtfG and GtfH glycosyltransferases and enzymes responsible for synthesis of cell wall polysaccharides (CwpB, CwpK), (ii) proteins responsible for the extracellular localization of proteins, such as structural components of the accessory SecA2Y2 system (Asp1, Asp2, SecA2) and the SrtA sortase, and (iii) the LiaR transcriptional response regulator. These mutations also influenced biofilm architecture, revealing that similar cell-to-cell interactions govern assembly of auto-aggregates and biofilm formation. We found that BglB, CshA, GtfH and LiaR were specifically associated with bacterial auto-aggregation, whereas Asp1, Asp2, CwpB, CwpK, GtfE, GtfG, SecA2 and SrtA also contributed to adhesion to host cells and host-derived components, or to interactions with the human pathogen Fusobacterium nucleatum. Our study demonstrates that our screening method could also be used to identify genes implicated in the bacterial interactions of pathogens or probiotics, for which aggregation is either a virulence trait or an advantageous feature, respectively.
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Affiliation(s)
- Benoit Couvigny
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Saulius Kulakauskas
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Nicolas Pons
- MetaGenoPoliS, INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Benoit Quinquis
- MetaGenoPoliS, INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | | | - Thierry Meylheuc
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.,INRA, Plateforme MIMA2, Jouy-en-Josas, France
| | - Christine Delorme
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Pierre Renault
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Romain Briandet
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Nicolas Lapaque
- MICALIS Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Eric Guédon
- STLO, UMR 1253, INRA, Agrocampus Ouest, Rennes, France
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9
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Sitkiewicz I. How to become a killer, or is it all accidental? Virulence strategies in oral streptococci. Mol Oral Microbiol 2017; 33:1-12. [PMID: 28727895 DOI: 10.1111/omi.12192] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2017] [Indexed: 01/03/2023]
Abstract
Streptococci are a diverse group of Gram-positive microorganisms sharing common virulence traits and similar strategies to escape the oral niche and establish an infection in other parts of the host organism. Invasive infection with oral streptococci is "a perfect storm" that requires the concerted action of multiple biotic and abiotic factors. Our understanding of streptococcal pathogenicity and infectivity should probably be less mechanistic and driven not only by the identification of novel virulence factors. The observed diversity of the genus, including the range of virulence and pathogenicity mechanisms, is most likely the result of interspecies interactions, a massive horizontal gene transfer between streptococci within a shared oral niche, recombination events, selection of specialized clones, and modification of regulatory circuits. Selective pressure by the host and bacterial communities is a driving force for the selection of virulence traits and shaping the streptococcal genome. Global regulatory events driving niche adaptation and interactions with bacterial communities and the host steer research interests towards attempts to define the oral interactome on the transcriptional level and define signal cross-feeding and co-expression and co-regulation of virulence genes.
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Affiliation(s)
- I Sitkiewicz
- Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland
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10
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Capsular Polysaccharide Expression in Commensal Streptococcus Species: Genetic and Antigenic Similarities to Streptococcus pneumoniae. mBio 2016; 7:mBio.01844-16. [PMID: 27935839 PMCID: PMC5111408 DOI: 10.1128/mbio.01844-16] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule production distinguishes S. pneumoniae from closely related commensals of the mitis group streptococci. Based on antigenic and genetic analyses of 187 mitis group streptococci, including 90 recognized serotypes of S. pneumoniae, we demonstrated capsule production by the Wzy/Wzx pathway in 74% of 66 S. mitis strains and in virtually all tested strains of S. oralis (subspecies oralis, dentisani, and tigurinus) and S. infantis. Additional analyses of genomes of S. cristatus, S. parasanguinis, S. australis, S. sanguinis, S. gordonii, S. anginosus, S. intermedius, and S. constellatus revealed complete capsular biosynthesis (cps) loci in all strains tested. Truncated cps loci were detected in three strains of S. pseudopneumoniae, in 26% of S. mitis strains, and in a single S. oralis strain. The level of sequence identities of cps locus genes confirmed that the structural polymorphism of capsular polysaccharides in S. pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S. pneumoniae raises concerns about potential misidentifications in addition to important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and for the pathogen. Expression of a capsular polysaccharide is among the principal virulence factors of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous assumptions, this study showed that expression of capsular polysaccharides by the same genetic mechanisms is a general property of closely related species of streptococci that form a significant part of our commensal microbiota. The demonstrated antigenic identity of many capsular polysaccharides expressed by commensal streptococci and S. pneumoniae raises important questions concerning the consequences for vaccination and host-parasite relationships both for the commensals and the pathogen.
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11
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Churton NWV, Misra RV, Howlin RP, Allan RN, Jefferies J, Faust SN, Gharbia SE, Edwards RJ, Clarke SC, Webb JS. Parallel Evolution in Streptococcus pneumoniae Biofilms. Genome Biol Evol 2016; 8:1316-26. [PMID: 27190203 PMCID: PMC4898793 DOI: 10.1093/gbe/evw072] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Streptococcus pneumoniae is a commensal human pathogen and the causative agent of various invasive and noninvasive diseases. Carriage of the pneumococcus in the nasopharynx is thought to be mediated by biofilm formation, an environment where isogenic populations frequently give rise to morphological colony variants, including small colony variant (SCV) phenotypes. We employed metabolic characterization and whole-genome sequencing of biofilm-derived S. pneumoniae serotype 22F pneumococcal SCVs to investigate diversification during biofilm formation. Phenotypic profiling revealed that SCVs exhibit reduced growth rates, reduced capsule expression, altered metabolic profiles, and increased biofilm formation compared to the ancestral strain. Whole-genome sequencing of 12 SCVs from independent biofilm experiments revealed that all SCVs studied had mutations within the DNA-directed RNA polymerase delta subunit (RpoE). Mutations included four large-scale deletions ranging from 51 to 264 bp, one insertion resulting in a coding frameshift, and seven nonsense single-nucleotide substitutions that result in a truncated gene product. This work links mutations in the rpoE gene to SCV formation and enhanced biofilm development in S. pneumoniae and therefore may have important implications for colonization, carriage, and persistence of the organism. Furthermore, recurrent mutation of the pneumococcal rpoE gene presents an unprecedented level of parallel evolution in pneumococcal biofilm development.
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Affiliation(s)
- Nicholas W V Churton
- Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom
| | - Raju V Misra
- Genomics Research Unit, Microbiology Services, Public Health England, Colindale, United Kingdom
| | - Robert P Howlin
- Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom
| | - Raymond N Allan
- Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, United Kingdom
| | - Johanna Jefferies
- Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom
| | - Saul N Faust
- Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, United Kingdom
| | - Saheer E Gharbia
- Genomics Research Unit, Microbiology Services, Public Health England, Colindale, United Kingdom
| | - Richard J Edwards
- Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Stuart C Clarke
- Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom Public Health England, Southampton, United Kingdom
| | - Jeremy S Webb
- Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom Institute for Life Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom
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12
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Aguayo S, Strange A, Gadegaard N, Dalby MJ, Bozec L. Influence of biomaterial nanotopography on the adhesive and elastic properties of Staphylococcus aureus cells. RSC Adv 2016. [DOI: 10.1039/c6ra12504b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Despite the well-known beneficial effects of biomaterial nanopatterning on host tissue integration, the influence of controlled nanoscale topography on bacterial colonisation and infection remains unknown.
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Affiliation(s)
- S. Aguayo
- Department of Biomaterials and Tissue Engineering
- UCL Eastman Dental Institute
- University College London
- London
- WC1X 8LD – UK
| | - A. Strange
- Department of Biomaterials and Tissue Engineering
- UCL Eastman Dental Institute
- University College London
- London
- WC1X 8LD – UK
| | - N. Gadegaard
- Division of Biomedical Engineering
- School of Engineering
- University of Glasgow
- UK
| | - M. J. Dalby
- Centre for Cell Engineering
- Institute of Molecular, Cell and Systems Biology
- University of Glasgow
- UK
| | - L. Bozec
- Department of Biomaterials and Tissue Engineering
- UCL Eastman Dental Institute
- University College London
- London
- WC1X 8LD – UK
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13
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Rukke H, Engen S, Schenck K, Petersen F. Capsule expression inStreptococcus mitismodulates interaction with oral keratinocytes and alters susceptibility to human antimicrobial peptides. Mol Oral Microbiol 2015; 31:302-13. [DOI: 10.1111/omi.12123] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2015] [Indexed: 12/21/2022]
Affiliation(s)
- H.V. Rukke
- Department of Oral Biology; Faculty of Dentistry; University of Oslo; Norway
| | - S.A. Engen
- Department of Oral Biology; Faculty of Dentistry; University of Oslo; Norway
| | - K. Schenck
- Department of Oral Biology; Faculty of Dentistry; University of Oslo; Norway
| | - F.C. Petersen
- Department of Oral Biology; Faculty of Dentistry; University of Oslo; Norway
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14
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Ouennane S, Leprohon P, Moineau S. Diverse virulent pneumophages infect Streptococcus mitis. PLoS One 2015; 10:e0118807. [PMID: 25692983 PMCID: PMC4334900 DOI: 10.1371/journal.pone.0118807] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 01/23/2015] [Indexed: 01/01/2023] Open
Abstract
Streptococcus mitis has emerged as one of the leading causes of bacterial endocarditis and is related to Streptococcus pneumoniae. Antibiotic resistance has also increased among strains of S. mitis and S. pneumoniae. Phages are being reinvestigated as alternatives to antibiotics for managing infections. In this study, the two virulent phages Cp-1 (Podoviridae) and Dp-1 (Siphoviridae), previously isolated from S. pneumoniae, were found to also infect S. mitis. Microbiological assays showed that both pneumophages could not only replicate in S. mitis but also produced more visible plaques on this host. However, the burst size and phage adsorption data were lower in S. mitis as compared to S. pneumoniae. A comparison of the genomes of each phage grown on both hosts produced identical nucleotide sequences, confirming that the same phages infect both bacterial species. We also discovered that the genomic sequence of podophage Cp-1 of the Félix d'Hérelle collection is different than the previously reported sequence and thus renamed SOCP.
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Affiliation(s)
- Siham Ouennane
- Département de Biochimie, Microbiologie et Bio-Informatique, Faculté des Sciences et de Génie, Groupe de Recherche en Écologie Buccale, Félix d’Hérelle Reference Center for Bacterial Viruses, Faculté de Médecine Dentaire, Université Laval, Québec City, Québec, Canada
| | - Philippe Leprohon
- Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec City, Québec, Canada
| | - Sylvain Moineau
- Département de Biochimie, Microbiologie et Bio-Informatique, Faculté des Sciences et de Génie, Groupe de Recherche en Écologie Buccale, Félix d’Hérelle Reference Center for Bacterial Viruses, Faculté de Médecine Dentaire, Université Laval, Québec City, Québec, Canada
- * E-mail:
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Straume D, Stamsås GA, Håvarstein LS. Natural transformation and genome evolution in Streptococcus pneumoniae. INFECTION GENETICS AND EVOLUTION 2014; 33:371-80. [PMID: 25445643 DOI: 10.1016/j.meegid.2014.10.020] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 10/16/2014] [Accepted: 10/23/2014] [Indexed: 01/30/2023]
Abstract
Streptococcus pneumoniae is a frequent colonizer of the human nasopharynx that has the potential to cause severe infections such as pneumonia, bacteremia and meningitis. Despite considerable efforts to reduce the burden of pneumococcal disease, it continues to be a major public health problem. After the Second World War, antimicrobial therapy was introduced to fight pneumococcal infections, followed by the first effective vaccines more than half a century later. These clinical interventions generated a selection pressure that drove the evolution of vaccine-escape mutants and strains that were highly resistant against antibiotics. The remarkable ability of S. pneumoniae to acquire drug resistance and evade vaccine pressure is due to its recombination-mediated genetic plasticity. S. pneumoniae is competent for natural genetic transformation, a property that enables the pneumococcus to acquire new traits by taking up naked DNA from the environment and incorporating it into its genome through homologous recombination. In the present paper, we review current knowledge on pneumococcal transformation, and discuss how the pneumococcus uses this mechanism to adapt and survive under adverse and fluctuating conditions.
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Affiliation(s)
- Daniel Straume
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Gro Anita Stamsås
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Leiv Sigve Håvarstein
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, NO-1432 Ås, Norway.
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16
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Engen SA, Valen Rukke H, Becattini S, Jarrossay D, Blix IJ, Petersen FC, Sallusto F, Schenck K. The oral commensal Streptococcus mitis shows a mixed memory Th cell signature that is similar to and cross-reactive with Streptococcus pneumoniae. PLoS One 2014; 9:e104306. [PMID: 25119879 PMCID: PMC4131883 DOI: 10.1371/journal.pone.0104306] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 07/07/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Carriage of and infection with Streptococcus pneumoniae is known to predominantly induce T helper 17 (Th17) responses in humans, but the types of Th cells showing reactivity towards commensal streptococci with low pathogenic potential, such as the oral commensals S. mitis and S. salivarius, remain uncharacterized. METHODS Memory CD4(+) T helper (Th) cell subsets were isolated from healthy human blood donors according to differential expression of chemokine receptors, expanded in vitro using polyclonal stimuli and characterized for reactivity against different streptococcal strains. RESULTS Th cells responding to S. mitis, S. salivarius and S. pneumoniae were predominantly in a CCR6(+)CXCR3(+) subset and produced IFN-γ, and in a CCR6(+)CCR4(+) subset and produced IL-17 and IL-22. Frequencies of S. pneumoniae-reactive Th cells were higher than frequencies of S. mitis- and S. salivarius-specific Th cells. S. mitis and S. pneumoniae isogenic capsule knock-out mutants and a S. mitis mutant expressing the serotype 4 capsule of S. pneumoniae showed no different Th cell responses as compared to wild type strains. S. mitis-specific Th17 cells showed cross-reactivity with S. pneumoniae. CONCLUSIONS As Th17 cells partly control clearance of S. pneumoniae, cross-reactive Th17 cells that may be induced by commensal bacterial species may influence the immune response, independent of capsule expression.
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Affiliation(s)
| | | | - Simone Becattini
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - David Jarrossay
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - Inger Johanne Blix
- Department of Oral Biology, University of Oslo, Oslo, Norway
- Department of Periodontology, University of Oslo, Oslo, Norway
| | | | - Federica Sallusto
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - Karl Schenck
- Department of Oral Biology, University of Oslo, Oslo, Norway
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17
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Engen SA, Valen Rukke H, Becattini S, Jarrossay D, Blix IJ, Petersen FC, Sallusto F, Schenck K. The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 order by 8029-- awyx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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18
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The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 order by 1-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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19
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The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 order by 1-- gadu] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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20
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The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 order by 1-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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21
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The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 order by 8029-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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22
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The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 order by 8029-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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23
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The Oral Commensal Streptococcus mitis Shows a Mixed Memory Th Cell Signature That Is Similar to and Cross-Reactive with Streptococcus pneumoniae. PLoS One 2014. [DOI: 10.1371/journal.pone.0104306 and 1880=1880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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24
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Protective role of the capsule and impact of serotype 4 switching on Streptococcus mitis. Infect Immun 2014; 82:3790-801. [PMID: 24958712 DOI: 10.1128/iai.01840-14] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The polysaccharide capsule surrounding Streptococcus pneumoniae is essential for virulence. Recently, Streptococcus mitis, a human commensal and a close relative of S. pneumoniae, was also shown to have a capsule. In this study, the S. mitis type strain switched capsule by acquisition of the serotype 4 capsule locus of S. pneumoniae TIGR4, following induction of competence for natural transformation. Comparison of the wild type with the capsule-switching mutant and with a capsule deletion mutant showed that the capsule protected S. mitis against phagocytosis by RAW 264.7 macrophages. This effect was enhanced in the S. mitis strain expressing the S. pneumoniae capsule, which showed, in addition, increased resistance against early clearance in a mouse model of lung infection. Expression of both capsules also favored survival in human blood, and the effect was again more pronounced for the capsule-switching mutant. S. mitis survival in horse blood or in a mouse model of bacteremia was not significantly different between the wild type and the mutant strains. In all models, S. pneumoniae TIGR4 showed higher rates of survival than the S. mitis type strain or the capsule-switching mutant, except in the lung model, in which significant differences between S. pneumoniae TIGR4 and the capsule-switching mutant were not observed. Thus, we identified conditions that showed a protective function for the capsule in S. mitis. Under such conditions, S. mitis resistance to clearance could be enhanced by capsule switching to serotype 4, but it was enhanced to levels lower than those for the virulent strain S. pneumoniae TIGR4.
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25
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Jakubovics NS, Yassin SA, Rickard AH. Community interactions of oral streptococci. ADVANCES IN APPLIED MICROBIOLOGY 2014; 87:43-110. [PMID: 24581389 DOI: 10.1016/b978-0-12-800261-2.00002-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
It is now clear that the most common oral diseases, dental caries and periodontitis, are caused by mixed-species communities rather than by individual pathogens working in isolation. Oral streptococci are central to these disease processes since they are frequently the first microorganisms to colonize oral surfaces and they are numerically the dominant microorganisms in the human mouth. Numerous interactions between oral streptococci and other bacteria have been documented. These are thought to be critical for the development of mixed-species oral microbial communities and for the transition from oral health to disease. Recent metagenomic studies are beginning to shed light on the co-occurrence patterns of streptococci with other oral bacteria. Refinements in microscopy techniques and biofilm models are providing detailed insights into the spatial distribution of streptococci in oral biofilms. Targeted genetic manipulation is increasingly being applied for the analysis of specific genes and networks that modulate interspecies interactions. From this work, it is clear that streptococci produce a range of extracellular factors that promote their integration into mixed-species communities and enable them to form social networks with neighboring taxa. These "community integration factors" include coaggregation-mediating adhesins and receptors, small signaling molecules such as peptides or autoinducer-2, bacteriocins, by-products of metabolism including hydrogen peroxide and lactic acid, and a range of extracellular enzymes. Here, we provide an overview of various types of community interactions between oral streptococci and other microorganisms, and we consider the possibilities for the development of new technologies to interfere with these interactions to help control oral biofilms.
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Affiliation(s)
- Nicholas S Jakubovics
- Oral Biology, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom.
| | - Sufian A Yassin
- Oral Biology, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Alexander H Rickard
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, USA
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