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Johnson CN, Wilde S, Tuomanen E, Rosch JW. Convergent impact of vaccination and antibiotic pressures on pneumococcal populations. Cell Chem Biol 2024; 31:195-206. [PMID: 38052216 PMCID: PMC10938186 DOI: 10.1016/j.chembiol.2023.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 09/08/2023] [Accepted: 11/07/2023] [Indexed: 12/07/2023]
Abstract
Streptococcus pneumoniae is a remarkably adaptable and successful human pathogen, playing dual roles of both asymptomatic carriage in the nasopharynx and invasive disease including pneumonia, bacteremia, and meningitis. Efficacious vaccines and effective antibiotic therapies are critical to mitigating morbidity and mortality. However, clinical interventions can be rapidly circumvented by the pneumococcus by its inherent proclivity for genetic exchange. This leads to an underappreciated interplay between vaccine and antibiotic pressures on pneumococcal populations. Circulating populations have undergone dramatic shifts due to the introduction of capsule-based vaccines of increasing valency imparting strong selective pressures. These alterations in population structure have concurrent consequences on the frequency of antibiotic resistance profiles in the population. This review will discuss the interactions of these two selective forces. Understanding and forecasting the drivers of antibiotic resistance and capsule switching are of critical importance for public health, particularly for such a genetically promiscuous pathogen as S. pneumoniae.
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Affiliation(s)
- Cydney N Johnson
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shyra Wilde
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Elaine Tuomanen
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Jason W Rosch
- Department of Host-Microbe Interactions, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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2
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Shi R, Lv R, Dong Z, Cao Q, Wu R, Liu S, Ren Y, Liu Z, van der Mei HC, Liu J, Busscher HJ. Magnetically-targetable outer-membrane vesicles for sonodynamic eradication of antibiotic-tolerant bacteria in bacterial meningitis. Biomaterials 2023; 302:122320. [PMID: 37738742 DOI: 10.1016/j.biomaterials.2023.122320] [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: 07/10/2023] [Revised: 09/06/2023] [Accepted: 09/09/2023] [Indexed: 09/24/2023]
Abstract
Treatment of acute bacterial meningitis is difficult due to the impermeability of the blood-brain barrier, greatly limiting the antibiotic concentrations that can be achieved in the brain. Escherichia coli grown in presence of iron-oxide magnetic nanoparticles secrete large amounts of magnetic outer-membrane vesicles (OMVs) in order to remove excess Fe from their cytoplasm. OMVs are fully biomimetic nanocarriers, but can be inflammatory. Here, non-inflammatory magnetic OMVs were prepared from an E. coli strain in which the synthesis of inflammatory lipid A acyltransferase was inhibited using CRISPR/Cas9 mediated gene knockout. OMVs were loaded with ceftriaxone (CRO) and meso-tetra-(4-carboxyphenyl)porphine (TCPP) and magnetically driven across the blood-brain barrier for sonodynamic treatment of bacterial meningitis. ROS-generation upon ultrasound application of CRO- and TCPP-loaded OMVs yielded similar ROS-generation as by TCPP in solution. In vitro, ROS-generation by CRO- and TCPP-loaded OMVs upon ultrasound application operated synergistically with CRO to kill a hard-to-kill, CRO-tolerant E. coli strain. In a mouse model of CRO-tolerant E. coli meningitis, CRO- and TCPP-loaded OMVs improved survival rates and clinical behavioral scores of infected mice after magnetic targeting and ultrasound application. Recurrence did not occur for at least two weeks after arresting treatment.
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Affiliation(s)
- Rui Shi
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China; University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands
| | - Rui Lv
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China
| | - Ziliang Dong
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China; Science and Technology Innovation Center, Shandong First Medical University, Jinan, 250000, Shandong, PR China
| | - Qinghua Cao
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China
| | - Renfei Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China; University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands
| | - Sidi Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China; University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands
| | - Yijin Ren
- University of Groningen and University Medical Center of Groningen, Department of Orthodontics, Hanzeplein 1, 9700 RB, Groningen, the Netherlands
| | - Zhuang Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China
| | - Henny C van der Mei
- University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands.
| | - Jian Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Rd, Suzhou, 215123, Jiangsu, PR China.
| | - Henk J Busscher
- University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands
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García E. Two putative glutamate decarboxylases of Streptococcus pneumoniae as possible antigens for the production of anti-GAD65 antibodies leading to type 1 diabetes mellitus. Int Microbiol 2023; 26:675-690. [PMID: 37154976 PMCID: PMC10165594 DOI: 10.1007/s10123-023-00364-y] [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: 01/11/2023] [Revised: 04/13/2023] [Accepted: 04/21/2023] [Indexed: 05/10/2023]
Abstract
Type 1 diabetes mellitus (T1DM) has been increasing in prevalence in the last decades and has become a global burden. Autoantibodies against human glutamate decarboxylase (GAD65) are among the first to be detected at the onset of T1DM. Diverse viruses have been proposed to be involved in the triggering of T1DM because of molecular mimicry, i.e., similarity between parts of some viral proteins and one or more epitopes of GAD65. However, the possibility that bacterial proteins might also be responsible for GAD65 mimicry has been seldom investigated. To date, many genomes of Streptococcus pneumoniae (the pneumococcus), a prominent human pathogen particularly prevalent among children and the elderly, have been sequenced. A dataset of more than 9000 pneumococcal genomes was mined and two different (albeit related) genes (gadA and gadB), presumably encoding two glutamate decarboxylases similar to GAD65, were found. The various gadASpn alleles were present only in serotype 3 pneumococci belonging to the global lineage GPSC83, although some homologs have also been discovered in two subspecies of Streptococcus constellatus (pharyngis and viborgensis), an isolate of the group B streptococci, and several strains of Lactobacillus delbrueckii. Besides, gadBSpn alleles are present in > 10% of the isolates in our dataset and represent 16 GPSCs with 123 sequence types and 20 different serotypes. Sequence analyses indicated that gadA- and gadB-like genes have been mobilized among different bacteria either by prophage(s) or by integrative and conjugative element(s), respectively. Substantial similarities appear to exist between the putative pneumococcal glutamate decarboxylases and well-known epitopes of GAD65. In this sense, the use of broader pneumococcal conjugate vaccines such as PCV20 would prevent the majority of serotypes expressing those genes that might potentially contribute to T1DM. These results deserve upcoming studies on the possible involvement of S. pneumoniae in the etiopathogenesis and clinical onset of T1DM.
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Affiliation(s)
- Ernesto García
- Departamento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040, Madrid, Spain.
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Oligopeptide Transporters of Nonencapsulated Streptococcus pneumoniae Regulate CbpAC and PspA Expression and Reduce Complement-Mediated Clearance. mBio 2023; 14:e0332522. [PMID: 36625598 PMCID: PMC9973307 DOI: 10.1128/mbio.03325-22] [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] [Indexed: 01/11/2023] Open
Abstract
Streptococcus pneumoniae colonizes the human nasopharynx and causes several diseases. Pneumococcal vaccines target the polysaccharide capsule and prevent most serious disease, but there has been an increase in the prevalence of nonencapsulated S. pneumoniae (NESp). Previously, it was thought that a capsule was necessary to cause invasive disease. NESp strains expressing the oligopeptide transporters AliC and AliD have been isolated from patients with invasive disease. The AliC and AliD oligopeptide transporters regulate the expression of several genes, including choline binding protein AC (CbpAC) (a homolog of PspA), which aids in reducing C3b deposition. It is hypothesized that by altering CbpAC expression, AliC and AliD provide protection from classical complement-mediated clearance by reducing C-reactive protein (CRP) binding. Our study demonstrates that AliC and AliD regulate CbpAC expression in NESp and that AliD found in certain serotypes of encapsulated strains regulates PspA expression. C3b deposition was increased in the NESp ΔaliD and encapsulated mutants in comparison to the wild type. NESp strains expressing AliC and AliD have a significant decrease in C1q and CRP deposition in comparison to the ΔaliC ΔaliD mutant. The complement protein C1q is required for NESp clearance in a murine model and increases opsonophagocytosis. By regulating CbpAC expression, NESp inhibits CRP binding to the bacterial surface and blocks classical complement activation, leading to greater systemic survival and virulence. Due to the increase in the prevalence of NESp, it is important to gain a better understanding of NESp virulence mechanisms that aid in establishing disease and persistence within a host by avoiding clearance by the immune system. IMPORTANCE Streptococcus pneumoniae (pneumococcus) can cause a range of diseases. Although there is a robust pneumococcal vaccination program that reduces invasive pneumococcal disease by targeting various polysaccharide capsules, there has been an increase in the isolation of nonvaccine serotypes and nonencapsulated S. pneumoniae (NESp) strains. While most studies of pneumococcal pathogenesis have focused on encapsulated strains, there is little understanding of how NESp causes disease. NESp lacks a protective capsule but contains novel genes, such as aliC and aliD, which have been shown to regulate the expression of numerous genes and to be required for NESp virulence and immune evasion. Furthermore, NESp strains have high transformation efficiencies and harbor resistance to multiple drugs. This could be deleterious to current treatment strategies employed for pneumococcal disease as NESp can be a reservoir of drug resistance genes. Therefore, deciphering how NESp survives within a host and facilitates disease is a necessity that will allow the fabrication of improved, broad-spectrum treatments and preventatives against pneumococcal disease. Our study provides a better understanding of NESp virulence mechanisms during host-pathogen interactions through the examination of genes directly regulated by the NESp proteins AliC and AliD.
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Platt MP, Lin YH, Penix T, Wiscovitch-Russo R, Vashee I, Mares CA, Rosch JW, Yu Y, Gonzalez-Juarbe N. A multiomics analysis of direct interkingdom dynamics between influenza A virus and Streptococcus pneumoniae uncovers host-independent changes to bacterial virulence fitness. PLoS Pathog 2022; 18:e1011020. [PMID: 36542660 PMCID: PMC9815659 DOI: 10.1371/journal.ppat.1011020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 01/05/2023] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND For almost a century, it has been recognized that influenza A virus (IAV) infection can promote the development of secondary bacterial infections (SBI) mainly caused by Streptococcus pneumoniae (Spn). Recent observations have shown that IAV is able to directly bind to the surface of Spn. To gain a foundational understanding of how direct IAV-Spn interaction alters bacterial biological fitness we employed combinatorial multiomic and molecular approaches. RESULTS Here we show IAV significantly remodels the global transcriptome, proteome and phosphoproteome profiles of Spn independently of host effectors. We identified Spn surface proteins that interact with IAV proteins (hemagglutinin, nucleoprotein, and neuraminidase). In addition, IAV was found to directly modulate expression of Spn virulence determinants such as pneumococcal surface protein A, pneumolysin, and factors associated with antimicrobial resistance among many others. Metabolic pathways were significantly altered leading to changes in Spn growth rate. IAV was also found to drive Spn capsule shedding and the release of pneumococcal surface proteins. Released proteins were found to be involved in evasion of innate immune responses and actively reduced human complement hemolytic and opsonizing activity. IAV also led to phosphorylation changes in Spn proteins associated with metabolism and bacterial virulence. Validation of proteomic data showed significant changes in Spn galactose and glucose metabolism. Furthermore, supplementation with galactose rescued bacterial growth and promoted bacterial invasion, while glucose supplementation led to enhanced pneumolysin production and lung cell apoptosis. CONCLUSIONS Here we demonstrate that IAV can directly modulate Spn biology without the requirement of host effectors and support the notion that inter-kingdom interactions between human viruses and commensal pathobionts can promote bacterial pathogenesis and microbiome dysbiosis.
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Affiliation(s)
- Maryann P. Platt
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, United States of America
| | - Yi-Han Lin
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, United States of America
| | - Trevor Penix
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Rosana Wiscovitch-Russo
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, United States of America
| | - Isha Vashee
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, United States of America
| | - Chris A. Mares
- Department of Life Sciences, Texas A&M University-San Antonio, Texas, United States of America
| | - Jason W. Rosch
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Yanbao Yu
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, United States of America
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, United States of America
| | - Norberto Gonzalez-Juarbe
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, United States of America
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Sakatani H, Kono M, Sugita G, Nanushaj D, Hijiya M, Iyo T, Shiga T, Murakami D, Kaku N, Yanagihara K, Nahm MH, Hotomi M. Investigation on the virulence of non-encapsulated Streptococcus pneumoniae using liquid agar pneumonia model. J Infect Chemother 2022; 28:1452-1458. [PMID: 35835387 DOI: 10.1016/j.jiac.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/14/2022] [Accepted: 07/04/2022] [Indexed: 10/31/2022]
Abstract
INTRODUCTION Since the introduction of pneumococcal conjugate vaccine, there have been warnings of an increase in infections caused by non-vaccine type of Streptococcus pneumoniae strains. Among them, nonencapsulated Streptococcus pneumoniae (NESp) has been reported to cause invasive infections, especially in children and the elderly. Due to low virulence, however, basic experimental reports on invasive infections are limited. METHODS We applied a liquid-agar method to establish a mouse model of invasive NESp infection. Mice were intratracheally administered a bacterial suspension including agar. With this technique, we investigated the pathogenicity of NESp and the effect of Pneumococcal surface protein K (PspK), a specific surface protein antigen of NESp. NESp wild-type strain (MNZ11) and NESp pspK-deleted mutant strain (MNZ1131) were used in this study. The survival rate, number of bacteria, cytokine/chemokine levels in the bronchoalveolar lavage fluid, and histology of the lung tissue were evaluated. RESULTS Mice that were intratracheally administered MNZ11 developed lethal pneumonia with bacteremia within 48 h. Conversely, MNZ1131 showed predominantly low lethality without significant pro-inflammatory cytokine production. NESp was found to cause severe pneumonia and bacteremia upon reaching the lower respiratory tract, and PspK was a critical factor of NESp for developing invasive infections. CONCLUSIONS The current study demonstrated the ability of NESp to develop invasive diseases, especially in connection with PspK by use of a mouse pneumonia model.
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Affiliation(s)
- Hideki Sakatani
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Masamitsu Kono
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Gen Sugita
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan; Sugita ENT Clinic, Mihama-Ku Takasu 3-14-1, Chiba City, Chiba, 261-0004, Japan
| | - Denisa Nanushaj
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Masayoshi Hijiya
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Takuro Iyo
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Tatsuya Shiga
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Daichi Murakami
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Norihito Kaku
- Department of Laboratory Medicine, Nagasaki University, Sakamoto 1-7-1, Nagasaki City, Nagasaki, 852-8501, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University, Sakamoto 1-7-1, Nagasaki City, Nagasaki, 852-8501, Japan
| | - Moon H Nahm
- Department of Medicine, University of Alabama at Birmingham, 1720 2nd Ave South Birmingham, Alabama, 35294, USA
| | - Muneki Hotomi
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan.
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Absence of Streptococcus pneumoniae Capsule Increases Bacterial Binding, Persistence, and Inflammation in Corneal Infection. Microorganisms 2022; 10:microorganisms10040710. [PMID: 35456761 PMCID: PMC9025271 DOI: 10.3390/microorganisms10040710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 03/07/2022] [Accepted: 03/22/2022] [Indexed: 11/17/2022] Open
Abstract
The role of the pneumococcal polysaccharide capsule is largely unclear for Streptococcus pneumoniae keratitis, an ocular inflammatory disease that develops as a result of bacterial infection of the cornea. In this study, capsule-deficient strains were compared to isogenic parent strains in their ability to adhere to human corneal epithelial cells. One isogenic pair was further used in topical ocular infection of mice to assess the contribution of the capsule to keratitis. The results showed that non-encapsulated pneumococci were significantly more adherent to cells, persisted in significantly higher numbers on mouse corneas in vivo, and caused significant increases in murine ocular IL9, IL10, IL12-p70, MIG, and MIP-1-gamma compared to encapsulated S. pneumoniae. These findings indicate that the bacterial capsule impedes virulence and the absence of capsule impacts inflammation following corneal infection.
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Kelly MS, Plunkett C, Yu Y, Aquino JN, Patel SM, Hurst JH, Young RR, Smieja M, Steenhoff AP, Arscott-Mills T, Feemster KA, Boiditswe S, Leburu T, Mazhani T, Patel MZ, Rawls JF, Jawahar J, Shah SS, Polage CR, Cunningham CK, Seed PC. Non-diphtheriae Corynebacterium species are associated with decreased risk of pneumococcal colonization during infancy. THE ISME JOURNAL 2022; 16:655-665. [PMID: 34511605 PMCID: PMC8857224 DOI: 10.1038/s41396-021-01108-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 08/22/2021] [Accepted: 09/03/2021] [Indexed: 02/08/2023]
Abstract
Streptococcus pneumoniae (pneumococcus) is a leading cause of severe infections among children and adults. Interactions between commensal microbes in the upper respiratory tract and S. pneumoniae are poorly described. In this study, we sought to identify interspecies interactions that modify the risk of S. pneumoniae colonization during infancy and to describe development of the upper respiratory microbiome during infancy in a sub-Saharan African setting. We collected nasopharyngeal swabs monthly (0-6 months of age) or bimonthly (6-12 months of age) from 179 mother-infant dyads in Botswana. We used 16S ribosomal RNA gene sequencing to characterize the nasopharyngeal microbiome and identified S. pneumoniae colonization using a species-specific PCR assay. We detect S. pneumoniae colonization in 144 (80%) infants at a median age of 71 days and identify a strong negative association between the relative abundance of the bacterial genera Corynebacterium within the infant nasopharyngeal microbiome and the risk of S. pneumoniae colonization. Using in vitro cultivation experiments, we demonstrate growth inhibition of S. pneumoniae by secreted factors from strains of several Corynebacterium species isolated from these infants. Finally, we demonstrate that antibiotic exposures and the winter season are associated with a decline in the relative abundance of Corynebacterium within the nasopharyngeal microbiome, while breastfeeding is associated with an increase in the Corynebacterium relative abundance. Our findings provide novel insights into the interspecies interactions that contribute to colonization resistance to S. pneumoniae and suggest that the nasopharyngeal microbiome may be a previously unrecognized mechanism by which environmental factors influence the risk of pneumococcal infections during childhood. Moreover, this work lays the foundation for future studies seeking to use targeted manipulation of the nasopharyngeal microbiome to prevent infections caused by S. pneumoniae.
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Affiliation(s)
- Matthew S. Kelly
- grid.7621.20000 0004 0635 5486Botswana-University of Pennsylvania Partnership, Gaborone, Botswana ,grid.26009.3d0000 0004 1936 7961Division of Pediatric Infectious Diseases, Duke University, Durham, NC USA
| | - Catherine Plunkett
- grid.16753.360000 0001 2299 3507Division of Pediatric Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL USA
| | - Yahe Yu
- grid.40803.3f0000 0001 2173 6074Department of Mathematics, North Carolina State University, Raleigh, NC USA
| | - Jhoanna N. Aquino
- grid.26009.3d0000 0004 1936 7961Division of Pediatric Infectious Diseases, Duke University, Durham, NC USA
| | - Sweta M. Patel
- grid.26009.3d0000 0004 1936 7961Division of Pulmonary Allergy, and Critical Care Medicine, Duke University, Durham, NC USA
| | - Jillian H. Hurst
- grid.26009.3d0000 0004 1936 7961Division of Pediatric Infectious Diseases, Duke University, Durham, NC USA
| | - Rebecca R. Young
- grid.26009.3d0000 0004 1936 7961Division of Pediatric Infectious Diseases, Duke University, Durham, NC USA
| | - Marek Smieja
- grid.25073.330000 0004 1936 8227Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON Canada
| | - Andrew P. Steenhoff
- grid.7621.20000 0004 0635 5486Botswana-University of Pennsylvania Partnership, Gaborone, Botswana ,grid.239552.a0000 0001 0680 8770Global Health Center, Children’s Hospital of Philadelphia, Philadelphia, PA USA ,grid.239552.a0000 0001 0680 8770Division of Pediatric Infectious Diseases, Children’s Hospital of Philadelphia, Philadelphia, PA USA
| | - Tonya Arscott-Mills
- grid.7621.20000 0004 0635 5486Botswana-University of Pennsylvania Partnership, Gaborone, Botswana ,grid.239552.a0000 0001 0680 8770Global Health Center, Children’s Hospital of Philadelphia, Philadelphia, PA USA
| | - Kristen A. Feemster
- grid.239552.a0000 0001 0680 8770Division of Pediatric Infectious Diseases, Children’s Hospital of Philadelphia, Philadelphia, PA USA
| | - Sefelani Boiditswe
- grid.7621.20000 0004 0635 5486Botswana-University of Pennsylvania Partnership, Gaborone, Botswana
| | - Tirayaone Leburu
- grid.7621.20000 0004 0635 5486Botswana-University of Pennsylvania Partnership, Gaborone, Botswana
| | - Tiny Mazhani
- grid.7621.20000 0004 0635 5486University of Botswana School of Medicine, Gaborone, Botswana
| | - Mohamed Z. Patel
- grid.7621.20000 0004 0635 5486University of Botswana School of Medicine, Gaborone, Botswana
| | - John F. Rawls
- grid.26009.3d0000 0004 1936 7961Department of Molecular Genetics and Microbiology, Duke University, Durham, NC USA
| | - Jayanth Jawahar
- grid.26009.3d0000 0004 1936 7961Department of Molecular Genetics and Microbiology, Duke University, Durham, NC USA
| | - Samir S. Shah
- grid.239573.90000 0000 9025 8099Divisions of Hospital Medicine and Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Christopher R. Polage
- grid.26009.3d0000 0004 1936 7961Department of Pathology, Duke University, Durham, NC USA
| | - Coleen K. Cunningham
- grid.26009.3d0000 0004 1936 7961Division of Pediatric Infectious Diseases, Duke University, Durham, NC USA
| | - Patrick C. Seed
- grid.16753.360000 0001 2299 3507Division of Pediatric Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL USA
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A novel pneumococcal surface protein K of nonencapsulated Streptococcus pneumoniae promotes transmission among littermates in an infant mouse model with influenza A virus co-infection. Infect Immun 2022; 90:e0062221. [PMID: 34978928 DOI: 10.1128/iai.00622-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We established an infant mouse model for colonization and transmission by nonencapsulated Streptococcus pneumoniae (NESp) strains to gain important information about its virulence among children. Invasive pneumococcal diseases have decreased dramatically since the worldwide introduction of pneumococcal capsular polysaccharide vaccines. Increasing prevalence of non-vaccine serotypes including NESp has been highlighted as a challenge in treatment strategy, but the virulence of NESp is not well understood. Protective strategy against NESp colonization and transmission between children require particularly urgent evaluation. NESp lacks capsules, a major virulent factor of pneumococci, but can cause a variety of infections in children and older people. PspK, a specific surface protein of NESp, is a key factor in establishing nasal colonization. In our infant mouse model for colonization and transmission by NESp strains, NESp could establish stable nasal colonization at the same level as encapsulated serotype 6A in infant mice, and could be transmitted between littermates. Transmission was promoted by NESp surface virulence factor PspK and influenza virus co-infection. However, PspK-deletion mutants lost the ability to colonize and transmit to new hosts. Promotion of NESp transmission by influenza was due to increased susceptibility of the new hosts. PspK was a key factor not only in establishment of nasal colonization, but also in transmission to new hosts. PspK may be targeted as a new candidate vaccine for NESp infection in children.
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McDaniel LS, Swiatlo E. If Not Now, When? Nonserotype Pneumococcal Protein Vaccines. Open Forum Infect Dis 2021; 8:ofab576. [PMID: 34934775 PMCID: PMC8684483 DOI: 10.1093/ofid/ofab576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 11/12/2021] [Indexed: 11/13/2022] Open
Abstract
The sudden emergence and global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have greatly accelerated the adoption of novel vaccine strategies, which otherwise would have likely languished for years. In this light, vaccines for certain other pathogens could certainly benefit from reconsideration. One such pathogen is Streptococcus pneumoniae (pneumococcus), an encapsulated bacterium that can express >100 antigenically distinct serotypes. Current pneumococcal vaccines are based exclusively on capsular polysaccharide—either purified alone or conjugated to protein. Since the introduction of conjugate vaccines, the valence of pneumococcal vaccines has steadily increased, as has the associated complexity and cost of production. There are many pneumococcal proteins invariantly expressed across all serotypes, which have been shown to induce robust immune responses in animal models. These proteins could be readily produced using recombinant DNA technology or by mRNA technology currently used in SARS-CoV-2 vaccines. A door may be opening to new opportunities in affordable and broadly protective vaccines.
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Affiliation(s)
- Larry S McDaniel
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Edwin Swiatlo
- Southeast Louisiana Veterans Health Care Network, New Orleans, Louisiana, USA
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11
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Capsule Promotes Intracellular Survival and Vascular Endothelial Cell Translocation during Invasive Pneumococcal Disease. mBio 2021; 12:e0251621. [PMID: 34634940 PMCID: PMC8510516 DOI: 10.1128/mbio.02516-21] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The polysaccharide capsule that surrounds Streptococcus pneumoniae (Spn) is one of its most important virulence determinants, serving to protect against phagocytosis. To date, 100 biochemical and antigenically distinct capsule types, i.e., serotypes, of Spn have been identified. Yet how capsule influences pneumococcal translocation across vascular endothelial cells (VEC), a key step in the progression of invasive disease, was unknown. Here, we show that despite capsule being inhibitory of Spn uptake by VEC, capsule enhances the escape rate of internalized pneumococci and thereby promotes translocation. Upon investigation, we determined that capsule protected Spn against intracellular killing by VEC and H2O2-mediated killing in vitro. Using a nitroblue tetrazolium reduction assay and nuclear magnetic resonance (NMR) analyses, purified capsule was confirmed as having antioxidant properties which varied according to serotype. Using an 11-member panel of isogenic capsule-switch mutants, we determined that serotype affected levels of Spn resistance to H2O2-mediated killing in vitro, with killing resistance correlated positively with survival duration within VEC, rate of transcytosis to the basolateral surface, and human attack rates. Experiments with mice supported our in vitro findings, with Spn producing oxidative-stress-resistant type 4 capsule being more organ-invasive than that producing oxidative-stress-sensitive type 2 capsule during bacteremia. Capsule-mediated protection against intracellular killing was also observed for Streptococcus pyogenes and Staphylococcus aureus. We conclude that capsular polysaccharide plays an important role within VEC, serving as an intracellular antioxidant, and that serotype-dependent differences in antioxidant capabilities impact the efficiency of VEC translocation and a serotype’s potential for invasive disease.
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12
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Briggs NS, Bruce KE, Naskar S, Winkler ME, Roper DI. The Pneumococcal Divisome: Dynamic Control of Streptococcus pneumoniae Cell Division. Front Microbiol 2021; 12:737396. [PMID: 34737730 PMCID: PMC8563077 DOI: 10.3389/fmicb.2021.737396] [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: 07/06/2021] [Accepted: 09/15/2021] [Indexed: 12/14/2022] Open
Abstract
Cell division in Streptococcus pneumoniae (pneumococcus) is performed and regulated by a protein complex consisting of at least 14 different protein elements; known as the divisome. Recent findings have advanced our understanding of the molecular events surrounding this process and have provided new understanding of the mechanisms that occur during the division of pneumococcus. This review will provide an overview of the key protein complexes and how they are involved in cell division. We will discuss the interaction of proteins in the divisome complex that underpin the control mechanisms for cell division and cell wall synthesis and remodelling that are required in S. pneumoniae, including the involvement of virulence factors and capsular polysaccharides.
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Affiliation(s)
- Nicholas S. Briggs
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Kevin E. Bruce
- Department of Biology, Indiana University Bloomington, Bloomington, IN, United States
| | - Souvik Naskar
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Malcolm E. Winkler
- Department of Biology, Indiana University Bloomington, Bloomington, IN, United States
| | - David I. Roper
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
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13
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Smith JT, Andam CP. Extensive Horizontal Gene Transfer within and between Species of Coagulase-Negative Staphylococcus. Genome Biol Evol 2021; 13:evab206. [PMID: 34498042 PMCID: PMC8462280 DOI: 10.1093/gbe/evab206] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2021] [Indexed: 01/10/2023] Open
Abstract
Members of the gram-positive bacterial genus Staphylococcus have historically been classified into coagulase-positive Staphylococcus (CoPS) and coagulase-negative Staphylococcus (CoNS) based on the diagnostic presentation of the coagulase protein. Previous studies have noted the importance of horizontal gene transfer (HGT) and recombination in the more well-known CoPS species Staphylococcus aureus, yet little is known of the contributions of these processes in CoNS evolution. In this study, we aimed to elucidate the phylogenetic relationships, genomic characteristics, and frequencies of HGT in CoNS, which are now being recognized as major opportunistic pathogens of humans. We compiled a data set of 1,876 publicly available named CoNS genomes. These can be delineated into 55 species based on allele differences in 462 core genes and variation in accessory gene content. CoNS species are a reservoir of transferrable genes associated with resistance to diverse classes of antimicrobials. We also identified nine types of the mobile genetic element SCCmec, which carries the methicillin resistance determinant mecA. Other frequently transferred genes included those associated with resistance to heavy metals, surface-associated proteins related to virulence and biofilm formation, type VII secretion system, iron capture, recombination, and metabolic enzymes. The highest frequencies of receipt and donation of recombined DNA fragments were observed in Staphylococcus capitis, Staphylococcus caprae, Staphylococcus hominis, Staphylococcus haemolyticus, and members of the Saprophyticus species group. The variable rates of recombination and biases in transfer partners imply that certain CoNS species function as hubs of gene flow and major reservoir of genetic diversity for the entire genus.
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Affiliation(s)
- Joshua T Smith
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire, USA
| | - Cheryl P Andam
- Department of Biological Sciences, University at Albany, State University of New York, New York, USA
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Tsang RSW. A Narrative Review of the Molecular Epidemiology and Laboratory Surveillance of Vaccine Preventable Bacterial Meningitis Agents: Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae and Streptococcus agalactiae. Microorganisms 2021; 9:449. [PMID: 33671611 PMCID: PMC7926440 DOI: 10.3390/microorganisms9020449] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/16/2021] [Accepted: 02/16/2021] [Indexed: 12/23/2022] Open
Abstract
This narrative review describes the public health importance of four most common bacterial meningitis agents, Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, and S. agalactiae (group B Streptococcus). Three of them are strict human pathogens that normally colonize the nasopharynx and may invade the blood stream to cause systemic infections and meningitis. S. agalactiae colonizes the genito-gastrointestinal tract and is an important meningitis agent in newborns, but also causes invasive infections in infants or adults. These four bacteria have polysaccharide capsules that protect them against the host complement defense. Currently licensed conjugate vaccines (against S. pneumoniae, H. influenza, and N. meningitidis only but not S. agalactiae) can induce protective serum antibodies in infants as young as two months old offering protection to the most vulnerable groups, and the ability to eliminate carriage of homologous serotype strains in vaccinated subjects lending further protection to those not vaccinated through herd immunity. However, the serotype-specific nature of these vaccines have driven the bacteria to adapt by mechanisms that affect the capsule antigens through either capsule switching or capsule replacement in addition to the possibility of unmasking of strains or serotypes not covered by the vaccines. The post-vaccine molecular epidemiology of vaccine-preventable bacterial meningitis is discussed based on findings obtained with newer genomic laboratory surveillance methods.
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Affiliation(s)
- Raymond S W Tsang
- Laboratory for Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada
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15
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Seid M, Beyene G, Alemu Y, Workalemahu B, Delbo M, Taddesse D, Biresaw G, Manilal A. Does cotrimoxazole prophylaxis in HIV patients increase the drug resistance of pneumococci? A comparative cross-sectional study in southern Ethiopia. PLoS One 2020; 15:e0243054. [PMID: 33284828 PMCID: PMC7721141 DOI: 10.1371/journal.pone.0243054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/15/2020] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Infections caused by antibiotic-resistant bacteria results in high rates of morbidity and mortality. Although the prolonged cotrimoxazole (CTX) prophylaxis is arguably associated with the risk of increasing drug resistance in the common pathogens, information regarding its impact on Streptococci pneumoniae / pneumococcus is very limited. OBJECTIVE This study was conducted to investigate the effect of cotrimoxazole prophylaxis on nasopharyngeal colonization rate and antimicrobial resistance using Streptococci pneumoniae (pneumococcus) as an indicator organism among HIV patients in Arba Minch, Ethiopia. MATERIALS AND METHODS A comparative cross-sectional study was designed and conducted among HIV patients attending the Anti-Retroviral Treatment (ART) clinic of Arba Minch General Hospital (AMGH) from April 01 to August 31, 2018. A total of 252 participants were systematically selected and clustered into two study groups based on their CTX prophylaxis status, one taking CTX prophylaxis, and the second one, the control group (without prophylaxis). A structured questionnaire was used to collect socio-demographic and clinical data from patients. A nasopharyngeal swab was collected and cultured for pneumococcal isolation and identification in accordance with standard microbiological techniques. An antibiotics sensitivity test was performed according to the CLSI guidelines. Data were analyzed using the Statistical package for social science (SPSS) version 20. The primary outcome was determined using logistic regression analysis. RESULTS Of the 252 enrolled HIV patients (mean age (37.38± 9.03 years), 144 (57.14%) were males. The overall, nasopharyngeal colonization rate of S. pneumoniae was 13.5% (95% CI: 8.4-15.6). Asymptomatic pneumococcal carriage rates among patients on CTX prophylaxis and the control group were 16.3%, and 10.3% respectively (p-value = 0.03). Regarding the risk factors analyzed, CTX prophylaxis (AOR: 2.2; 95% CI: 1.05-4.9) and gender (AOR: 2.5; 95% CI: 1.09-5.93) were significantly associated with pneumococcal colonization, showing a male preponderance. Cotrimoxazole-resistant pneumococci were 85.7% vs. 47.4% in the prophylaxis group and the control group respectively and it was statistically significant (AOR: 6.7; 95% CI: 1.3-36). Percentages of multi-drug resistant isolates in these two groups were 38.09 and 15.38 respectively (p-value = 0.04). Among the CTX resistant pneumococci isolates, 85% were also found to be co-resistant towards penicillin and was statistically significant. CONCLUSION The percentage prevalence of nasopharyngeal pneumococci colonization was higher in patients taking CTX prophylaxis. It was noted that CTX prophylaxis eventually results in the selection of cotrimoxazole resistance and multi-drug resistance in pneumococci. There is evidence of existing cross-resistance between cotrimoxazole and penicillin antibiotics. Therefore, CTX prophylaxis must be administered judiciously. Surveillance for antimicrobial susceptibility is warranted where the prophylaxis is common.
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Affiliation(s)
- Mohammed Seid
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
- * E-mail: (MS); (AM)
| | - Getnet Beyene
- Department of Medical Laboratory Sciences and Pathology, Jimma University, Jimma, Ethiopia
| | - Yared Alemu
- Department of Medical Laboratory Sciences and Pathology, Jimma University, Jimma, Ethiopia
| | - Bereket Workalemahu
- Department of Medical Laboratory Science, Arba Minch College of Health Sciences, Arba Minch, Ethiopia
| | - Mulugeta Delbo
- Department of Medical Laboratory Science, Arba Minch College of Health Sciences, Arba Minch, Ethiopia
| | - Dagimawie Taddesse
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Gelila Biresaw
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Aseer Manilal
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
- * E-mail: (MS); (AM)
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16
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Häfner S. Streptococcal oddity: Article highlight based on "pspK acquisition contributes to the loss of capsule in pneumococci: molecular characterisation of non-encapsulated pneumococci" by Takeaki Wajima et al. Microbes Infect 2020; 22:392-396. [PMID: 32693303 DOI: 10.1016/j.micinf.2020.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 07/06/2020] [Indexed: 10/23/2022]
Affiliation(s)
- Sophia Häfner
- University of Copenhagen, BRIC Biotech Research & Innovation Centre, Lund Group, 2200 Copenhagen, Denmark.
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17
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Kucinskaite-Kodze I, Simanavicius M, Dapkunas J, Pleckaityte M, Zvirbliene A. Mapping of Recognition Sites of Monoclonal Antibodies Responsible for the Inhibition of Pneumolysin Functional Activity. Biomolecules 2020; 10:biom10071009. [PMID: 32650398 PMCID: PMC7408604 DOI: 10.3390/biom10071009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/01/2020] [Accepted: 07/04/2020] [Indexed: 02/07/2023] Open
Abstract
The pathogenicity of many bacteria, including Streptococcus pneumoniae, depends on pore-forming toxins (PFTs) that cause host cell lysis by forming large pores in cholesterol-containing cell membranes. Therefore, PFTs-neutralising antibodies may provide useful tools for reducing S. pneumoniae pathogenic effects. This study aimed at the development and characterisation of monoclonal antibodies (MAbs) with neutralising activity to S. pneumoniae PFT pneumolysin (PLY). Five out of 10 produced MAbs were able to neutralise the cytolytic activity of PLY on a lung epithelial cell line. Epitope mapping with a series of recombinant overlapping PLY fragments revealed that neutralising MAbs are directed against PLY loops L1 and L3 within domain 4. The epitopes of MAbs 3A9, 6E5 and 12F11 located at L1 loop (aa 454–471) were crucial for PLY binding to the immobilised cholesterol. In contrast, the MAb 12D10 recognising L3 (aa 403–423) and the MAb 3F3 against the conformational epitope did not interfere with PLY-cholesterol interaction. Due to conformation-dependent binding, the approach to use overlapping peptides for fine epitope mapping of the neutralising MAbs was unsuccessful. Therefore, the epitopes recognised by the MAbs were analysed using computational methods. This study provides new data on PLY sites involved in functional activity.
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18
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Wajima T, Ishikawa H, Matsuzawa AI, Yamashita K, Suzuki S, Osato R, Nakaminami H, Noguchi N. pspK acquisition contributes to the loss of capsule in pneumococci: molecular characterisation of non-encapsulated pneumococci. Microbes Infect 2020; 22:451-456. [PMID: 32470393 DOI: 10.1016/j.micinf.2020.05.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 03/04/2020] [Accepted: 05/15/2020] [Indexed: 01/03/2023]
Abstract
With the introduction of the pneumococcal conjugate vaccine (PCV), the number of cases of non-vaccine type pneumococci and non-encapsulated Streptococcus pneumoniae (NESp) infection have increased. In order to clarify how pspK-harbouring NESp might have emerged, we characterised NESp and analysed the correlation between transformation and non-encapsulation. A total of 26 NESp strains were used in this study. The genetic backgrounds were compared using multilocus sequence typing (MLST). The ΔpspK::ermB strain, in which pspK was replaced by ermB in NESp, was constructed by homologous recombination. The genomic DNA of the ΔpspK::ermB strain was transformed into two types of encapsulated S. pneumoniae via transformation. The fitness of the parent and non-encapsulated transformants was compared using the growth curve. All NESp had pspK instead of capsular coding regions and were classified into 14 types by MLST, which indicated that NESp had several genetic backgrounds. Transformation of ΔpspK::ermB genomic DNA resulted in 10-4‒10-5 non-encapsulated transformants. Non-encapsulated transformants could grow faster than the encapsulated parent strain. The acquisition of pspK region via transformation contributed to the loss of encapsulation with high frequency. The present results suggest that non-encapsulation through pspK acquisition could be a potential mechanism to evade PCV.
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Affiliation(s)
- Takeaki Wajima
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.
| | - Haruna Ishikawa
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Akane Iris Matsuzawa
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Kanae Yamashita
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Shiori Suzuki
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Ryuji Osato
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Hidemasa Nakaminami
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Norihisa Noguchi
- Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
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19
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20
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Ung L, Bispo PJM, Bryan NC, Andre C, Chodosh J, Gilmore MS. The Best of All Worlds: Streptococcus pneumoniae Conjunctivitis through the Lens of Community Ecology and Microbial Biogeography. Microorganisms 2019; 8:microorganisms8010046. [PMID: 31881682 PMCID: PMC7022640 DOI: 10.3390/microorganisms8010046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/16/2019] [Accepted: 12/21/2019] [Indexed: 12/16/2022] Open
Abstract
The study of the forces which govern the geographical distributions of life is known as biogeography, a subject which has fascinated zoologists, botanists and ecologists for centuries. Advances in our understanding of community ecology and biogeography—supported by rapid improvements in next generation sequencing technology—have now made it possible to identify and explain where and why life exists as it does, including within the microbial world. In this review, we highlight how a unified model of microbial biogeography, one which incorporates the classic ecological principles of selection, diversification, dispersion and ecological drift, can be used to explain community dynamics in the settings of both health and disease. These concepts operate on a multiplicity of temporal and spatial scales, and together form a powerful lens through which to study microbial population structures even at the finest anatomical resolutions. When applied specifically to curious strains of conjunctivitis-causing, nonencapsulated Streptococcus pneumoniae, we show how this conceptual framework can be used to explain the possible evolutionary and disease-causing mechanisms which allowed these lineages to colonize and invade a separate biogeography. An intimate knowledge of this radical bifurcation in phylogeny, still the only known niche subspecialization for S. pneumoniae to date, is critical to understanding the pathogenesis of ocular surface infections, nature of host-pathogen interactions, and developing strategies to curb disease transmission.
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Affiliation(s)
- Lawson Ung
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Paulo J. M. Bispo
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Noelle C. Bryan
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
- Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences, Cambridge, MA 02139, USA
| | - Camille Andre
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - James Chodosh
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Michael S. Gilmore
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA; (L.U.); (P.J.M.B.); (C.A.); (J.C.)
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
- Correspondence: ; Tel.: +1-617-523-7900
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