scholarly journals Streptococcus pneumoniae: a Plethora of Temperate Bacteriophages With a Role in Host Genome Rearrangement

Author(s):  
Antonio J. Martín-Galiano ◽  
Ernesto García

Bacteriophages (phages) are viruses that infect bacteria. They are the most abundant biological entity on Earth (current estimates suggest there to be perhaps 1031 particles) and are found nearly everywhere. Temperate phages can integrate into the chromosome of their host, and prophages have been found in abundance in sequenced bacterial genomes. Prophages may modulate the virulence of their host in different ways, e.g., by the secretion of phage-encoded toxins or by mediating bacterial infectivity. Some 70% of Streptococcus pneumoniae (the pneumococcus)—a frequent cause of otitis media, pneumonia, bacteremia and meningitis—isolates harbor one or more prophages. In the present study, over 4000 S. pneumoniae genomes were examined for the presence of prophages, and nearly 90% were found to contain at least one prophage, either defective (47%) or present in full (43%). More than 7000 complete putative integrases, either of the tyrosine (6243) or serine (957) families, and 1210 full-sized endolysins (among them 1180 enzymes corresponding to 318 amino acid-long N-acetylmuramoyl-L-alanine amidases [LytAPPH]) were found. Based on their integration site, 26 different pneumococcal prophage groups were documented. Prophages coding for tRNAs, putative virulence factors and different methyltransferases were also detected. The members of one group of diverse prophages (PPH090) were found to integrate into the 3’ end of the host lytASpn gene encoding the major S. pneumoniae autolysin without disrupting it. The great similarity of the lytASpnand lytAPPH genes (85–92% identity) allowed them to recombine, via an apparent integrase-independent mechanism, to produce different DNA rearrangements within the pneumococcal chromosome. This study provides a complete dataset that can be used to further analyze pneumococcal prophages, their evolutionary relationships, and their role in the pathogenesis of pneumococcal disease.

Mobile DNA ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Francesco Santoro ◽  
Valeria Fox ◽  
Alessandra Romeo ◽  
Elisa Lazzeri ◽  
Gianni Pozzi ◽  
...  

Abstract Background Tn5253, a composite Integrative Conjugative Element (ICE) of Streptococcus pneumoniae carrying tet(M) and cat resistance determinants, was found to (i) integrate at specific 83-bp integration site (attB), (ii) produce circular forms joined by a 84-bp sequence (attTn), and (iii) restore the chromosomal integration site. The purpose of this study is to functionally characterize the attB in S. pneumoniae strains with different genetic backgrounds and in other bacterial species, and to investigate the presence of Tn5253 attB site into bacterial genomes. Results Analysis of representative Tn5253-carryng transconjugants obtained in S. pneumoniae strains with different genetic backgrounds and in other bacterial species, namely Streptococcus agalactiae, Streptococcus gordonii, Streptococcus pyogenes, and Enterococcus faecalis showed that: (i) Tn5253 integrates in rbgA of S. pneumoniae and in orthologous rbgA genes of other bacterial species, (ii) integration occurs always downstream of a 11-bp sequence conserved among streptococcal and enterococcal hosts, (iii) length of the attB site corresponds to length of the duplication after Tn5253 integration, (iv) attB duplication restores rbgA CDS, (v) Tn5253 produced circular forms containing the attTn site at a concentration ranging between 2.0 × 10−5 to 1.2 × 10−2 copies per chromosome depending on bacterial species and strain, (vi) reconstitution of attB sites occurred at 3.7 × 10−5 to 1.7 × 10−2 copies per chromosome. A database search of complete microbial genomes using Tn5253 attB as a probe showed that (i) thirteen attB variants were present in the 85 complete pneumococcal genomes, (ii) in 75 pneumococcal genomes (88.3 %), the attB site was 83 or 84 nucleotides in length, while in 10 (11.7 %) it was 41 nucleotides, (iii) in other 19 bacterial species attB was located in orthologous rbgA genes and its size ranged between 17 and 84 nucleotides, (iv) the 11-bp sequence, which correspond to the last 11 nucleotides of attB sites, is conserved among the different bacterial species and can be considered the core of the Tn5253 integration site. Conclusions A functional characterization of the Tn5253 attB integration site combined with genome analysis contributed to elucidating the potential of Tn5253 horizontal gene transfer among different bacterial species.


mBio ◽  
2011 ◽  
Vol 2 (5) ◽  
Author(s):  
Masahide Yano ◽  
Shruti Gohil ◽  
J. Robert Coleman ◽  
Catherine Manix ◽  
Liise-anne Pirofski

ABSTRACTThe use of pneumococcal capsular polysaccharide (PPS)-based vaccines has resulted in a substantial reduction in invasive pneumococcal disease. However, much remains to be learned about vaccine-mediated immunity, as seven-valent PPS-protein conjugate vaccine use in children has been associated with nonvaccine serotype replacement and 23-valent vaccine use in adults has not prevented pneumococcal pneumonia. In this report, we demonstrate that certain PPS-specific monoclonal antibodies (MAbs) enhance the transformation frequency of two differentStreptococcus pneumoniaeserotypes. This phenomenon was mediated by PPS-specific MAbs that agglutinate but do not promote opsonic effector cell killing of the homologous serotypeinvitro. Compared to the autoinducer, competence-stimulating peptide (CSP) alone, transcriptional profiling of pneumococcal gene expression after incubation with CSP and one such MAb to the PPS of serotype 3 revealed changes in the expression of competence (com)-related and bacteriocin-like peptide (blp) genes involved in pneumococcal quorum sensing. This MAb was also found to induce a nearly 2-fold increase in CSP2-mediated bacterial killing or fratricide. These observations reveal a novel, direct effect of PPS-binding MAbs on pneumococcal biology that has important implications for antibody immunity to pneumococcus in the pneumococcal vaccine era. Taken together, our data suggest heretofore unsuspected mechanisms by which PPS-specific antibodies could affect genetic exchange and bacterial viability in the absence of host cells.IMPORTANCECurrent thought holds that pneumococcal capsular polysaccharide (PPS)-binding antibodies protect against pneumococcus by inducing effector cell opsonic killing of the homologous serotype. While such antibodies are an important part of how pneumococcal vaccines protect against pneumococcal disease, PPS-specific antibodies that do not exhibit this activity but are highly protective against pneumococcus in mice have been identified. This article examines the effect of nonopsonic PPS-specific monoclonal antibodies (MAbs) on the biology ofStreptococcus pneumoniae. The results showed that in the presence of a competence-stimulating peptide (CSP), such MAbs increase the frequency of pneumococcal transformation. Further studies with one such MAb showed that it altered the expression of genes involved in quorum sensing and increased competence-induced killing or fratricide. These findings reveal a novel, previously unsuspected mechanism by which certain PPS-specific antibodies exert a direct effect on pneumococcal biology that has broad implications for bacterial clearance, genetic exchange, and antibody immunity to pneumococcus.


2005 ◽  
Vol 12 (1) ◽  
pp. 218-223 ◽  
Author(s):  
Daniel J. Sikkema ◽  
Nancy A. Ziembiec ◽  
Thomas R. Jones ◽  
Stephen W. Hildreth ◽  
Dace V. Madore ◽  
...  

ABSTRACT Weight-based assignments for immunoglobulin G1 (IgG1) and IgG2 subclass antibodies to Streptococcus pneumoniae capsular polysaccharides (PnPs) in antipneumococcal standard reference serum lot 89-S (lot 89-S), also known as lot 89-SF, have been determined for serotypes 1, 4, 5, 7F, 9V, and 18C. This extends the usefulness of lot 89-S beyond the IgG1 and IgG2 subclass assignments for serotypes 3, 6B, 14, 19F, and 23F made previously (A. Soininen, H. Kayhty, I. Seppala, and T. Wuorimaa, Clin. Diagn. Lab. Immunol. 5:561-566, 1998) to cover 11 major serotypes associated with the highest percentage of pneumococcal disease worldwide. A method of equivalence of absorbances in enzyme immunosorbent assays was used to determine the IgG1 and IgG2 antibody concentrations for the additional serotypes in lot 89-S, based on the subclass values previously assigned for PnPs serotypes 6B, 14, and 23F. This cross-standardization method assures consistency with previous antibody assignments in that reference serum. The newly assigned subclass values for serotype 9V, and previously assigned values for serotype 14, were used to quantitate PnPs antibodies in sera from adult and pediatric subjects immunized with a pneumococcal conjugate vaccine. There was a predominance of IgG1 anti-PnPs antibodies in pediatric sera and IgG2 anti-PnPs antibodies in the adult sera. The IgG1 and IgG2 subclass assignments for the 11 PnPs serotypes in antipneumococcal standard reference serum lot 89-S are useful for quantitating and characterizing immune responses to pneumococcal infection and vaccination regimens.


2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Parham Sendi ◽  
Eva Maria Moser Schaub ◽  
Konstantinos Nirgianakis ◽  
Lucy J. Hathaway ◽  
Pascal Bittel ◽  
...  

Abstract This report describes a case of relapsing pneumococcal peritonitis. The postulated source of infection was vaginal colonization and secondary adherence of pneumococci to an intrauterine contraceptive device. After immunization with a conjugate pneumococcal vaccine, her antibody levels were observed. She remained infection free at the 2-year follow-up investigation.


2020 ◽  
Author(s):  
Maile T. Phillips ◽  
Joshua L. Warren ◽  
Noga Givon-Lavi ◽  
Adrienn Tothpal ◽  
Gili Regev-Yochay ◽  
...  

ABSTRACTStreptococcus pneumoniae remains a leading cause of morbidity and mortality. Pneumococcal conjugate vaccines (PCVs) are effective but target only a fraction of the more than 90 pneumococcal serotypes. As a result, the introduction of PCVs has been followed by the emergence of non-vaccine serotypes. With higher-valency PCVs currently under development, there is a need to understand and predict patterns of serotype replacement to anticipate future changes. In this study, we evaluated patterns of change in serotype prevalence post-PCV introduction in Israel. We found that the assumption that non-vaccine serotypes increase by the same proportion overestimates changes in serotype prevalence in Jewish and Bedouin children. Furthermore, pre-vaccine prevalence was positively associated with increases in prevalence over the study period. From our analyses, serotypes 12F, 8, 16F, 33F, 9N, 7B, 10A, 22F, 24F, and 17F were estimated to have gained the most cases of invasive pneumococcal disease through serotype replacement in the Jewish population. However, this model also failed to quantify some additional cases gained, suggesting that changes in carriage in children alone may be insufficient to explain serotype replacement in disease. Understanding of serotype replacement is important as higher-valency vaccines are introduced.


2013 ◽  
Vol 141 (1-2) ◽  
pp. 48-53 ◽  
Author(s):  
Ina Gajic ◽  
Vera Mijac ◽  
Lazar Ranin ◽  
Dragana Andjelkovic ◽  
Miroslava Radicevic ◽  
...  

Introduction. Streptococcus pneumoniae is one of the leading causes of bacterial meningitis and sepsis. Invasive pneumococcal disease is a significant medical problem worldwide, particularly in children, due to a huge increase of pneumococcal resistance to antibiotics. Objective. The aim of the study was to investigate the antimicrobial susceptibility pattern of invasive pneumococcal isolates, as well as to determine whether decreased S. pneumoniae susceptibility to antibiotics was related to a particular serotype. Methods. Antimicrobial susceptibility to 19 antibiotics was determined in 58 invasive pneumococcal strains that were collected from seven regional centers during the period July 2009 to February 2011 in the National Reference Laboratory for streptococci and pneumococci. Results. The overall nonsusceptibility rate to penicillin was detected in 34% of pneumococcal isolates and to erythromycin in 36%. Higher resistance rates were observed among children than among adults. Penicillin resistance rate was 65% in children versus 22% in adults, while erythromycin nonsusceptibility rate was 47% in children versus 32% in adults. Co-resistance to penicillin and erythromycin was detected in 21% strains, mostly isolated from children. Multiresistance was found in one third of isolates. All strains were susceptible to vancomycin, linezolid, fluoroquinolones, telithromycin and rifampicin, while 23 (40%) isolates were susceptible to all tested antibiotics. The most common resistant serotypes were 19F and 14. Conclusion. The study has revealed that penicillin and macrolide resistance among invasive pneumococcal isolates is very high in Serbia. This emphasizes the need for continuous monitoring for invasive pneumococcal disease to document the serotype distribution and antimicrobial susceptibility pattern.


2018 ◽  
Vol 33 (5) ◽  
Author(s):  
Salim Parker ◽  
Anwar A. Hoosen ◽  
Charles Feldman ◽  
Amgad Gamil ◽  
Jerusha Naidoo ◽  
...  

The Hajj is the largest annual mass gathering on Earth. Respiratory infections are one of the leading causes of disease and hospitalisation during the pilgrimage, with pneumonia and influenza most common among these infections despite the availability of prophylactic vaccines. In fact, immunisation against influenza and pneumococcal disease is currently not a requirement for South African pilgrims entering Saudi Arabia. This review examines the burden of respiratory infections during the Hajj, particularly pneumonia and influenza, with a focus on pilgrims from South Africa. Although the number of South African pilgrims attending the Hajj has been capped at 2 000 since 2013, 30 000 South Africans perform the minor Umrah pilgrimage annually. Understanding the aetiology of disease in this group could have implications for medical resourcing during the Hajj.


F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 1699
Author(s):  
Michael Walekhwa ◽  
Margaret Muturi ◽  
Eucharia Kenya ◽  
Beatrice Kabera

Background: The spread of antimicrobial resistance threatens effective control and treatment of pneumococcal disease worldwide. In Kenya, an estimated one in every five children dies from pneumococcal disease every year. Of these, ≥50% are attributable to antibiotic resistance. Consequently, the WHO has recommended that continuous regional surveillance be done to detect early resistance to available antibiotics and make necessary changes. We therefore investigated antimicrobial susceptibility patterns of Streptococcus pneumoniae among PCV-10 vaccinated and unvaccinated children ≤5 years old at Gertrude's Children’s Hospital. Methods: A 0.5 McFarland standard of freshly subcultured organisms were inoculated on Mueller–Hinton plates with 5% sheep blood agar. A standard disk dispenser was used to dispense various antibiotic disks on the Mueller–Hinton agar plate. Incubation was done overnight (20-24 hours) at 37oC in 5% CO2 and clearance zones read using a Vanier caliber. Antimicrobials tested included vancomycin (30µg, ≥17mm); erythromycin (15µg, ≥21mm); clindamycin (2µg, ≥19mm); oxacillin (1µg, ≥19mm) and ceftriaxone (1µg, ≥30mm). Results: Thirty nine (92.86%) Streptococcus pneumoniae isolates were susceptible to erythromycin; 39 (92.86%) were susceptible to vancomycin; eight (19.86%) Streptococcus pneumoniae isolates were susceptible to oxacillin, while 34 (80.95%) were non-susceptible; 40 (95.24%) isolates were susceptible to clindamycin; and 24 (57.86%) isolates were susceptible to ceftriaxone, while 18 (42.86%) were non-susceptible. Children who attended daycare centers exhibited a four-fold significant risk of being resistant to ceftriaxone. All antibiotics studied were effective against Streptococcus pneumoniae except oxacillin and ceftriaxone, which exhibited high levels of non-susceptibility. Attendance of daycare centers, consumption of antibiotics two weeks prior to collection of sample and subject age were shown to be associated with an increased risk of Streptococcus pneumoniae being resistant to penicillins and ceftriaxone. Conclusions: The law guiding use of antibiotics in Kenya should be meritoriously enforced to curb abuse of the available antibiotics.


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