1
|
Li H, Cao J, Han Q, Li Z, Zhuang J, Wang C, Wang H, Luo Z, Wang B, Li A. Protease SfpB plays an important role in cell membrane stability and immune system evasion in Streptococcus agalactiae. Microb Pathog 2024; 192:106683. [PMID: 38735447 DOI: 10.1016/j.micpath.2024.106683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/14/2024]
Abstract
Bacteria possess the ability to develop diverse and ingenious strategies to outwit the host immune system, and proteases are one of the many weapons employed by bacteria. This study sought to identify S. agalactiae additional serine protease and determine its role in virulence. The S. agalactiae THN0901 genome features one S8 family serine peptidase B (SfpB), acting as a secreted and externally exposed entity. A S8 family serine peptidase mutant strain (ΔsfpB) and complement strain (CΔsfpB) were generated through homologous recombination. Compared to the wild-type strain THN0901, the absorption of EtBr dyes was significantly reduced (P < 0.01) in ΔsfpB, implying an altered cell membrane permeability. In addition, the ΔsfpB strain had a significantly lower survival rate in macrophages (P < 0.01) and a 61.85 % lower adhesion ability to the EPC cells (P < 0.01) compared to THN0901. In the in vivo colonization experiment using tilapia as a model, 210 fish were selected and injected with different bacterial strains at a concentration of 3 × 106 CFU/tail. At 6, 12, 24, 48, 72 and 96 h post-injection, three fish were randomly selected from each group and their brain, liver, spleen, and kidney tissues were isolated. Subsequently, it was demonstrated that the ΔsfpB strain exhibited a markedly diminished capacity for colonization in tilapia. Additionally, the cumulative mortality of ΔsfpB in fish after intraperitoneal injection was reduced by 19.92-23.85 %. In conclusion, the findings in this study have demonstrated that the SfpB plays a significant role in S. agalactiae cell membrane stability and immune evasion. The immune evasion is fundamental for the development and transmission of invasive diseases, the serine protease SfpB may be a promising candidate for the development of antimicrobial agents to reduce the transmission of S. agalactiae.
Collapse
Affiliation(s)
- Han Li
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Jizhen Cao
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Qing Han
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Zhicheng Li
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Jingyu Zhuang
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Chenxi Wang
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Hebing Wang
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Zhi Luo
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Baotun Wang
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Anxing Li
- State Key Laboratory of Biocontrol/Guangdong Provincial Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China.
| |
Collapse
|
2
|
Liu Y, Ai H. Current research update on group B streptococcal infection related to obstetrics and gynecology. Front Pharmacol 2024; 15:1395673. [PMID: 38953105 PMCID: PMC11215423 DOI: 10.3389/fphar.2024.1395673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Accepted: 05/31/2024] [Indexed: 07/03/2024] Open
Abstract
Group B streptococcal (GBS) is a Gram-positive bacterium that is commonly found in the gastrointestinal tract and urogenital tract. GBS infestation during pregnancy is a significant contributor to maternal and neonatal morbidity and mortality globally. This article aims to discuss the infectious diseases caused by GBS in the field of obstetrics and gynecology, as well as the challenges associated with the detection, treatment, and prevention of GBS.
Collapse
Affiliation(s)
| | - Hao Ai
- Liaoning Provincial Key Laboratory of Follicular Development and Reproductive Health, Jinzhou Medical University, Jinzhou, Liaoning, China
| |
Collapse
|
3
|
Hager-Mair FF, Bloch S, Schäffer C. Glycolanguage of the oral microbiota. Mol Oral Microbiol 2024. [PMID: 38515284 DOI: 10.1111/omi.12456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 02/13/2024] [Accepted: 02/13/2024] [Indexed: 03/23/2024]
Abstract
The oral cavity harbors a diverse and dynamic bacterial biofilm community which is pivotal to oral health maintenance and, if turning dysbiotic, can contribute to various diseases. Glycans as unsurpassed carriers of biological information are participating in underlying processes that shape oral health and disease. Bacterial glycoinfrastructure-encompassing compounds as diverse as glycoproteins, lipopolysaccharides (LPSs), cell wall glycopolymers, and exopolysaccharides-is well known to influence bacterial fitness, with direct effects on bacterial physiology, immunogenicity, lifestyle, and interaction and colonization capabilities. Thus, understanding oral bacterias' glycoinfrastructure and encoded glycolanguage is key to elucidating their pathogenicity mechanisms and developing targeted strategies for therapeutic intervention. Driven by their known immunological role, most research in oral glycobiology has been directed onto LPSs, whereas, recently, glycoproteins have been gaining increased interest. This review draws a multifaceted picture of the glycolanguage, with a focus on glycoproteins, manifested in prominent oral bacteria, such as streptococci, Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum. We first define the characteristics of the different glycoconjugate classes and then summarize the current status of knowledge of the structural diversity of glycoconjugates produced by oral bacteria, describe governing biosynthetic pathways, and list biological roles of these energetically costly compounds. Additionally, we highlight emerging research on the unraveling impact of oral glycoinfrastructure on dental caries, periodontitis, and systemic conditions. By integrating current knowledge and identifying knowledge gaps, this review underscores the importance of studying the glycolanguage oral bacteria speak to advance our understanding of oral microbiology and develop novel antimicrobials.
Collapse
Affiliation(s)
- Fiona F Hager-Mair
- Department of Chemistry, NanoGlycobiology Research Group, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Susanne Bloch
- Department of Chemistry, NanoGlycobiology Research Group, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
- Competence Center for Periodontal Research, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria
| | - Christina Schäffer
- Department of Chemistry, NanoGlycobiology Research Group, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| |
Collapse
|
4
|
Kamińska D, Ratajczak M, Nowak-Malczewska DM, Karolak JA, Kwaśniewski M, Szumala-Kakol A, Dlugaszewska J, Gajecka M. Macrolide and lincosamide resistance of Streptococcus agalactiae in pregnant women in Poland. Sci Rep 2024; 14:3877. [PMID: 38366099 PMCID: PMC10873391 DOI: 10.1038/s41598-024-54521-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 02/13/2024] [Indexed: 02/18/2024] Open
Abstract
Knowing about the antibiotic resistance, serotypes, and virulence-associated genes of Group B Streptococcus for epidemiological and vaccine development is very important. We have determined antimicrobial susceptibility patterns, serotype, and virulence profiles. The antibiotic susceptibility was assessed for a total of 421 Streptococcus agalactiae strains, isolated from pregnant women and neonates. Then, 89 erythromycin and/or clindamycin-resistant strains (82 isolates obtained from pregnant women and seven isolates derived from neonates) were assessed in detail. PCR techniques were used to identify the studied strains, perform serotyping, and assess genes encoding selected virulence factors. Phenotypic and genotypic methods determined the mechanisms of resistance. All tested strains were sensitive to penicillin and levofloxacin. The constitutive MLSB mechanism (78.2%), inducible MLSB mechanism (14.9%), and M phenotype (6.9%) were identified in the macrolide-resistant strains. It was found that macrolide resistance is strongly associated with the presence of the ermB gene and serotype V. FbsA, fbsB, fbsC, scpB, and lmb formed the most recurring pattern of genes among the nine surface proteins whose genes were analysed. A minority (7.9%) of the GBS isolates exhibited resistance to lincosamides and macrolides, or either, including those that comprised the hypervirulent clone ST-17. The representative antibiotic resistance pattern consisted of erythromycin, clindamycin, and tetracycline resistance (71.9%). An increase in the fraction of strains resistant to macrolides and lincosamides indicates the need for monitoring both the susceptibility of these strains and the presence of the ST-17 clone.
Collapse
Affiliation(s)
- Dorota Kamińska
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland
| | - Magdalena Ratajczak
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland
| | - Dorota M Nowak-Malczewska
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland
| | - Justyna A Karolak
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland
| | - Marek Kwaśniewski
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland
| | - Anna Szumala-Kakol
- Unit of Microbiology, Gynecological and Obstetric Clinical Hospital, Poznan University of Medical Sciences, Polna 33, 60-535, Poznan, Poland
| | - Jolanta Dlugaszewska
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland
| | - Marzena Gajecka
- Chair and Department of Genetics and Pharmaceutical Microbiology, Collegium Pharmaceuticum, Poznan University of Medical Sciences, Rokietnicka 3, 60-806, Poznan, Poland.
- Institute of Human Genetics, Polish Academy of Sciences, Strzeszynska 32, 60-479, Poznan, Poland.
| |
Collapse
|
5
|
Cinar MS, Niyas A, Avci FY. Serine-rich repeat proteins: well-known yet little-understood bacterial adhesins. J Bacteriol 2024; 206:e0024123. [PMID: 37975670 PMCID: PMC10810200 DOI: 10.1128/jb.00241-23] [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] [Indexed: 11/19/2023] Open
Abstract
Serine-rich-repeat proteins (SRRPs) are large mucin-like glycoprotein adhesins expressed by a plethora of pathogenic and symbiotic Gram-positive bacteria. SRRPs play major functional roles in bacterial-host interactions, like adhesion, aggregation, biofilm formation, virulence, and pathogenesis. Through their functional roles, SRRPs aid in the development of host microbiomes but also diseases like infective endocarditis, otitis media, meningitis, and pneumonia. SRRPs comprise shared domains across different species, including two or more heavily O-glycosylated long stretches of serine-rich repeat regions. With loci that can be as large as ~40 kb and can encode up to 10 distinct glycosyltransferases that specifically facilitate SRRP glycosylation, the SRRP loci makes up a significant portion of the bacterial genome. The significance of SRRPs and their glycans in host-microbe communications is becoming increasingly evident. Studies are beginning to reveal the glycosylation pathways and mature O-glycans presented by SRRPs. Here we review the glycosylation machinery of SRRPs across species and discuss the functional roles and clinical manifestations of SRRP glycosylation.
Collapse
Affiliation(s)
- Mukaddes S. Cinar
- Department of Biochemistry, Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Afaq Niyas
- Department of Biochemistry, Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Fikri Y. Avci
- Department of Biochemistry, Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, USA
| |
Collapse
|
6
|
Aminov R, Aminova L. The role of the glycome in symbiotic host-microbe interactions. Glycobiology 2023; 33:1106-1116. [PMID: 37741057 PMCID: PMC10876039 DOI: 10.1093/glycob/cwad073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 09/13/2023] [Accepted: 09/21/2023] [Indexed: 09/25/2023] Open
Abstract
Glycosylation plays a crucial role in many aspects of cell biology, including cellular and organismal integrity, structure-and-function of many glycosylated molecules in the cell, signal transduction, development, cancer, and in a number of diseases. Besides, at the inter-organismal level of interaction, a variety of glycosylated molecules are involved in the host-microbiota recognition and initiation of downstream signalling cascades depending on the outcomes of the glycome-mediated ascertainment. The role of glycosylation in host-microbe interactions is better elaborated within the context of virulence and pathogenicity in bacterial infection processes but the symbiotic host-microbe relationships also involve substantive glycome-mediated interactions. The works in the latter field have been reviewed to a much lesser extent, and the main aim of this mini-review is to compensate for this deficiency and summarise the role of glycomics in host-microbe symbiotic interactions.
Collapse
Affiliation(s)
- Rustam Aminov
- The School of Medicine, Medical Sciences and Nutrition, Foresterhill Campus, Aberdeen AB25 2ZD, Scotland, United Kingdom
| | - Leila Aminova
- Midwest Bioprocessing Center, 801 W Main St, Peoria, IL, 61606-1877, United States
| |
Collapse
|
7
|
Kobierecka P, Wyszyńska A, Aleksandrzak-Piekarczyk T, Sałańska A, Gawor J, Bardowski J, Jagusztyn Krynicka KE. Genomic and transcriptomic analysis of Ligilactobacillus salivarius IBB3154-in search of new promoters for vaccine construction. Microbiol Spectr 2023; 11:e0284423. [PMID: 37982628 PMCID: PMC10715006 DOI: 10.1128/spectrum.02844-23] [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: 07/12/2023] [Accepted: 10/16/2023] [Indexed: 11/21/2023] Open
Abstract
IMPORTANCE The genome of the strain Ligilactobacillus salivarius IBB3154 was sequenced, and transcriptome analysis was carried out at two different temperatures, allowing the determination of gene expression levels in response to environmental changes (temperature). Genes with higher expression at 42°C were identified. The use of a reporter gene (β- glucuronidase) did not confirm the transcriptomic results; it was found that the promoters of the genes sasA1 and sasA2 were active in the presence of bile salts. This opens up new opportunities for the overexpression of genes of other bacterial species in Ligilactobacillus cells in the intestinal environment.
Collapse
Affiliation(s)
- Patrycja Kobierecka
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Agnieszka Wyszyńska
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | | | - Agnieszka Sałańska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jan Gawor
- DNA Sequencing and Synthesis Facility, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jacek Bardowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | |
Collapse
|
8
|
Estevens R, Mil-Homens D, Fialho AM. In-Silico Analysis Highlights the Existence in Members of Burkholderia cepacia Complex of a New Class of Adhesins Possessing Collagen-like Domains. Microorganisms 2023; 11:1118. [PMID: 37317093 DOI: 10.3390/microorganisms11051118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/18/2023] [Accepted: 04/22/2023] [Indexed: 06/16/2023] Open
Abstract
Burkholderia cenocepacia is a multi-drug-resistant lung pathogen. This species synthesizes various virulence factors, among which cell-surface components (adhesins) are critical for establishing the contact with host cells. This work in the first part focuses on the current knowledge about the adhesion molecules described in this species. In the second part, through in silico approaches, we perform a comprehensive analysis of a group of unique bacterial proteins possessing collagen-like domains (CLDs) that are strikingly overrepresented in the Burkholderia species, representing a new putative class of adhesins. We identified 75 CLD-containing proteins in Burkholderia cepacia complex (Bcc) members (Bcc-CLPs). The phylogenetic analysis of Bcc-CLPs revealed the evolution of the core domain denominated "Bacterial collagen-like, middle region". Our analysis remarkably shows that these proteins are formed by extensive sets of compositionally biased residues located within intrinsically disordered regions (IDR). Here, we discuss how IDR functions may increase their efficiency as adhesion factors. Finally, we provided an analysis of a set of five homologs identified in B. cenocepacia J2315. Thus, we propose the existence in Bcc of a new type of adhesion factors distinct from the described collagen-like proteins (CLPs) found in Gram-positive bacteria.
Collapse
Affiliation(s)
- Ricardo Estevens
- Department of Bioengineering, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Dalila Mil-Homens
- Department of Bioengineering, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
- Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
- Institute for Health and Bioeconomic (i4HB), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Arsenio M Fialho
- Department of Bioengineering, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
- Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
- Institute for Health and Bioeconomic (i4HB), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| |
Collapse
|
9
|
Cell-surface protein YwfG of Lactococcus lactis binds to α-1,2-linked mannose. PLoS One 2023; 18:e0273955. [PMID: 36602978 DOI: 10.1371/journal.pone.0273955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 12/06/2022] [Indexed: 01/06/2023] Open
Abstract
Lactococcus lactis strains are used as starter cultures in the production of fermented dairy and vegetable foods, but the species also occurs in other niches such as plant material. Lactococcus lactis subsp. lactis G50 (G50) is a plant-derived strain and potential candidate probiotics. Western blotting of cell-wall proteins using antibodies generated against whole G50 cells detected a 120-kDa protein. MALDI-TOF MS analysis identified it as YwfG, a Leu-Pro-any-Thr-Gly cell-wall-anchor-domain-containing protein. Based on a predicted domain structure, a recombinant YwfG variant covering the N-terminal half (aa 28-511) of YwfG (YwfG28-511) was crystallized and the crystal structure was determined. The structure consisted of an L-type lectin domain, a mucin-binding protein domain, and a mucus-binding protein repeat. Recombinant YwfG variants containing combinations of these domains (YwfG28-270, YwfG28-336, YwfG28-511, MubR4) were prepared and their interactions with monosaccharides were examined by isothermal titration calorimetry; the only interaction observed was between YwfG28-270, which contained the L-type lectin domain, and d-mannose. Among four mannobioses, α-1,2-mannobiose had the highest affinity for YwfG28-270 (dissociation constant = 34 μM). YwfG28-270 also interacted with yeast mannoproteins and yeast mannan. Soaking of the crystals of YwfG28-511 with mannose or α-1,2-mannobiose revealed that both sugars bound to the L-type lectin domain in a similar manner, although the presence of the mucin-binding protein domain and the mucus-binding protein repeat within the recombinant protein inhibited the interaction between the L-type lectin domain and mannose residues. Three of the YwfG variants (except MubR4) induced aggregation of yeast cells. Strain G50 also induced aggregation of yeast cells, which was abolished by deletion of ywfG from G50, suggesting that surface YwfG contributes to the interaction with yeast cells. These findings provide new structural and functional insights into the interaction between L. lactis and its ecological niche via binding of the cell-surface protein YwfG with mannose.
Collapse
|
10
|
Group B Streptococcus: Virulence Factors and Pathogenic Mechanism. Microorganisms 2022; 10:microorganisms10122483. [PMID: 36557736 PMCID: PMC9784991 DOI: 10.3390/microorganisms10122483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/10/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Group B Streptococcus (GBS) or Streptococcus agalactiae is a major cause of neonatal mortality. When colonizing the lower genital tract of pregnant women, GBS may cause premature birth and stillbirth. If transmitted to the newborn, it may result in life-threatening illnesses, including sepsis, meningitis, and pneumonia. Moreover, through continuous evolution, GBS can use its original structure and unique factors to greatly improve its survival rate in the human body. This review discusses the key virulence factors that facilitate GBS invasion and colonization and their action mechanisms. A comprehensive understanding of the role of virulence factors in GBS infection is crucial to develop better treatment options and screen potential candidate molecules for the development of the vaccine.
Collapse
|
11
|
Okahashi N, Nakata M, Kuwata H, Kawabata S. Oral mitis group streptococci: A silent majority in our oral cavity. Microbiol Immunol 2022; 66:539-551. [PMID: 36114681 DOI: 10.1111/1348-0421.13028] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/11/2022] [Accepted: 09/12/2022] [Indexed: 12/13/2022]
Abstract
Members of the oral mitis group streptococci including Streptococcus oralis, Streptococcus sanguinis, and Streptococcus gordonii are the most abundant inhabitants of human oral cavity and dental plaque, and have been implicated in infectious complications such as bacteremia and infective endocarditis. Oral mitis group streptococci are genetically close to Streptococcus pneumoniae; however, they do not produce cytolysin (pneumolysin), which is a key virulence factor of S. pneumoniae. Similar to S. pneumoniae, oral mitis group streptococci possess several cell surface proteins that bind to the cell surface components of host mammalian cells. S. sanguinis expresses long filamentous pili that bind to the matrix proteins of host cells. The cell wall-anchored nuclease of S. sanguinis contributes to the evasion of the neutrophil extracellular trap by digesting its web-like extracellular DNA. Oral mitis group streptococci produce glucosyltransferases, which synthesize glucan (glucose polymer) from sucrose of dietary origin. Neuraminidase (NA) is a virulent factor in oral mitis group streptococci. Influenza type A virus (IAV) relies on viral NA activity to release progeny viruses from infected cells and spread the infection, and NA-producing oral streptococci elevate the risk of IAV infection. Moreover, oral mitis group streptococci produce hydrogen peroxide (H2 O2 ) as a by-product of sugar metabolism. Although the concentrations of streptococcal H2 O2 are low (1-2 mM), they play important roles in bacterial competition in the oral cavity and evasion of phagocytosis by host macrophages and neutrophils. In this review, we intended to describe the diverse pathogenicity of oral mitis group streptococci.
Collapse
Affiliation(s)
- Nobuo Okahashi
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan.,Center for Frontier Oral Science, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
| | - Masanobu Nakata
- Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Hirotaka Kuwata
- Department of Oral Microbiology and Immunology, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
| | - Shigetada Kawabata
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
| |
Collapse
|
12
|
Pham H, Tran TDT, Yang Y, Ahn JH, Hur HG, Kim YH. Analysis of phylogenetic markers for classification of a hydrogen peroxide producing Streptococcus oralis isolated from saliva by a newly devised differential medium. J Microbiol 2022; 60:795-805. [DOI: 10.1007/s12275-022-2261-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 06/22/2022] [Accepted: 06/23/2022] [Indexed: 11/30/2022]
|
13
|
Kremer PHC, Ferwerda B, Bootsma HJ, Rots NY, Wijmenga-Monsuur AJ, Sanders EAM, Trzciński K, Wyllie AL, Turner P, van der Ende A, Brouwer MC, Bentley SD, van de Beek D, Lees JA. Pneumococcal genetic variability in age-dependent bacterial carriage. eLife 2022; 11:e69244. [PMID: 35881438 PMCID: PMC9395192 DOI: 10.7554/elife.69244] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 07/03/2022] [Indexed: 11/13/2022] Open
Abstract
The characteristics of pneumococcal carriage vary between infants and adults. Host immune factors have been shown to contribute to these age-specific differences, but the role of pathogen sequence variation is currently less well-known. Identification of age-associated pathogen genetic factors could leadto improved vaccine formulations. We therefore performed genome sequencing in a large carriage cohort of children and adults and combined this with data from an existing age-stratified carriage study. We compiled a dictionary of pathogen genetic variation, including serotype, strain, sequence elements, single-nucleotide polymorphisms (SNPs), and clusters of orthologous genes (COGs) for each cohort - all of which were used in a genome-wide association with host age. Age-dependent colonization showed weak evidence of being heritable in the first cohort (h2 = 0.10, 95% CI 0.00-0.69) and stronger evidence in the second cohort (h2 = 0.56, 95% CI 0.23-0.87). We found that serotypes and genetic background (strain) explained a proportion of the heritability in the first cohort (h2serotype = 0.07, 95% CI 0.04-0.14 and h2GPSC = 0.06, 95% CI 0.03-0.13) and the second cohort (h2serotype = 0.11, 95% CI 0.05-0.21 and h2GPSC = 0.20, 95% CI 0.12-0.31). In a meta-analysis of these cohorts, we found one candidate association (p=1.2 × 10-9) upstream of an accessory Sec-dependent serine-rich glycoprotein adhesin. Overall, while we did find a small effect of pathogen genome variation on pneumococcal carriage between child and adult hosts, this was variable between populations and does not appear to be caused by strong effects of individual genes. This supports proposals for adaptive future vaccination strategies that are primarily targeted at dominant circulating serotypes and tailored to the composition of the pathogen populations.
Collapse
Affiliation(s)
- Philip HC Kremer
- Department of Neurology, Amsterdam UMC, University of AmsterdamMeibergdreefNetherlands
| | - Bart Ferwerda
- Department of Neurology, Amsterdam UMC, University of AmsterdamMeibergdreefNetherlands
- Department of Clinical Epidemiology, Biostatistics and Bioinformatics, University of AmsterdamAmsterdamNetherlands
| | - Hester J Bootsma
- Centre for Infectious Disease Control, National Institute for Public Health and the EnvironmentBilthovenNetherlands
| | - Nienke Y Rots
- Centre for Infectious Disease Control, National Institute for Public Health and the EnvironmentBilthovenNetherlands
| | - Alienke J Wijmenga-Monsuur
- Centre for Infectious Disease Control, National Institute for Public Health and the EnvironmentBilthovenNetherlands
| | - Elisabeth AM Sanders
- Centre for Infectious Disease Control, National Institute for Public Health and the EnvironmentBilthovenNetherlands
- Department of Pediatric Immunology and Infectious D, Wilhelmina Children's HospitalUtrechtNetherlands
| | - Krzysztof Trzciński
- Department of Pediatric Immunology and Infectious D, Wilhelmina Children's HospitalUtrechtNetherlands
| | - Anne L Wyllie
- Department of Pediatric Immunology and Infectious D, Wilhelmina Children's HospitalUtrechtNetherlands
- Epidemiology of Microbial Diseases, Yale School of Public HealthNew HavenUnited States
| | - Paul Turner
- Cambodia Oxford Medical Research Unit, Angkor Hospital for ChildrenSiem ReapCambodia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Arie van der Ende
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMCAmsterdamNetherlands
- The Netherlands Reference Laboratory for Bacterial MeningitisAmsterdamNetherlands
| | - Matthijs C Brouwer
- Department of Neurology, Amsterdam UMC, University of AmsterdamMeibergdreefNetherlands
| | - Stephen D Bentley
- Parasites and Microbes, Wellcome Sanger InstituteCambridgeUnited Kingdom
| | - Diederik van de Beek
- Department of Neurology, Amsterdam UMC, University of AmsterdamMeibergdreefNetherlands
| | - John A Lees
- European Molecular Biology Laboratory–European Bioinformatics InstituteCambridgeUnited Kingdom
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College LondonLondonUnited Kingdom
| |
Collapse
|
14
|
Abstract
Purpose of review Community-acquired bacterial meningitis is a continually changing disease. This review summarises both dynamic epidemiology and emerging data on pathogenesis. Updated clinical guidelines are discussed, new agents undergoing clinical trials intended to reduce secondary brain damage are presented. Recent findings Conjugate vaccines are effective against serotype/serogroup-specific meningitis but vaccine escape variants are rising in prevalence. Meningitis occurs when bacteria evade mucosal and circulating immune responses and invade the brain: directly, or across the blood–brain barrier. Tissue damage is caused when host genetic susceptibility is exploited by bacterial virulence. The classical clinical triad of fever, neck stiffness and headache has poor diagnostic sensitivity, all guidelines reflect the necessity for a low index of suspicion and early Lumbar puncture. Unnecessary cranial imaging causes diagnostic delays. cerebrospinal fluid (CSF) culture and PCR are diagnostic, direct next-generation sequencing of CSF may revolutionise diagnostics. Administration of early antibiotics is essential to improve survival. Dexamethasone partially mitigates central nervous system inflammation in high-income settings. New agents in clinical trials include C5 inhibitors and daptomycin, data are expected in 2025. Summary Clinicians must remain vigilant for bacterial meningitis. Constantly changing epidemiology and emerging pathogenesis data are increasing the understanding of meningitis. Prospects for better treatments are forthcoming.
Collapse
|