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BMC Veterinary Research Nov 2023Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen. Orphan response regulator CovR plays crucial regulative functions in the survivability and...
BACKGROUND
Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen. Orphan response regulator CovR plays crucial regulative functions in the survivability and pathogenicity of S. suis 2. However, research on the CovR in S. suis 2 is limited.
RESULTS
In this study, the regulative functions of CovR in the survivability and pathogenicity were investigated in S. suis 2 isolated from a diseased pig. The deletion of CovR significantly weakened the survivability and pathogenicity of S. suis 2. Compared with the wild-type strain, ΔcovR showed slower growth rates and thinner capsular polysaccharides. Moreover, ΔcovR showed reduced adhesion and invasion to Hep-2 cells as well as anti-phagocytosis and anti-killing ability to 3D4 cells and anti-serum killing ability. In addition, the deletion of CovR significantly reduced the colonisation ability of S. suis 2 in mice. The survival rate of mice infected with ΔcovR was increased by 16.7% compared with that of mice infected with S. suis 2. Further, the deletion of CovR led to dramatic changes in metabolism-related pathways in S. suis 2, five of those, including fructose and mannose metabolism, glycerolipid metabolism, ABC transporters, amino sugar and nucleotide sugar metabolism and phosphotransferase system, were significantly down-regulated.
CONCLUSIONS
Based on the results, CovR plays positive regulative functions in the survivability and pathogenicity of S. suis 2 SC19 strain isolated from a pig.
Topics: Animals; Mice; Bacterial Proteins; Serogroup; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases; Virulence; Virulence Factors
PubMed: 37990198
DOI: 10.1186/s12917-023-03808-9 -
Vaccines Jan 2024() is a zoonotic pathogen with multiple serotypes, and thus, multivalent vaccines generating cross-protection against infections are urgently needed to improve animal...
() is a zoonotic pathogen with multiple serotypes, and thus, multivalent vaccines generating cross-protection against infections are urgently needed to improve animal welfare and reduce antibiotic abuse. In this study, we established a systematic and comprehensive epitope prediction pipeline based on immunoinformatics. Ten candidate epitopes were ultimately selected for building the multi-epitope vaccine (MVSS) against infections. The ten epitopes of MVSS were all derived from highly conserved, immunogenic, and virulence-associated surface proteins in . In silico analyses revealed that MVSS was structurally stable and affixed with immune receptors, indicating that it would likely trigger strong immunological reactions in the host. Furthermore, mice models demonstrated that MVSS elicited high titer antibodies and diminished damages in serotype 2 and Chz infection, significantly reduced sequelae, induced cytokine transcription, and decreased organ bacterial burdens after triple vaccination. Meanwhile, anti-rMVSS serum inhibited five important serotypes in vitro, exerted beneficial protective effects against infections and significantly reduced histopathological damage in mice. Given the above, it is possible to develop MVSS as a universal subunit vaccine against multiple serotypes of infections.
PubMed: 38400121
DOI: 10.3390/vaccines12020137 -
Journal of Applied Microbiology Aug 2023To survey antibiotic susceptibility of bacteria causing cattle and pig respiratory infections in 10 European countries.
AIMS
To survey antibiotic susceptibility of bacteria causing cattle and pig respiratory infections in 10 European countries.
METHODS AND RESULTS
Non-replicate nasopharyngeal/nasal or lung swabs were collected from animals with acute respiratory signs during 2015-2016. Pasteurella multocida, Mannheimia haemolytica, Histophilus somni from cattle (n = 281), and P. multocida, Actinobacillus pleuropneumoniae, Glaesserella parasuis, Bordetella bronchiseptica, and Streptococcus suis from pigs (n = 593) were isolated. MICs were assessed following CLSI standards and interpreted using veterinary breakpoints where available. Histophilus somni isolates were fully antibiotic susceptible. Bovine P. multocida and M. haemolytica were susceptible to all antibiotics, except tetracycline (11.6%-17.6% resistance). Low macrolide and spectinomycin resistance was observed for P. multocida and M. haemolytica (1.3%-8.8%). Similar susceptibility was observed in pigs, where breakpoints are available. Resistance in P. multocida, A. pleuropneumoniae, and S. suis to ceftiofur, enrofloxacin, and florfenicol was absent or <5%. Tetracycline resistance varied from 10.6% to 21.3%, but was 82.4% in S. suis. Overall multidrug-resistance was low. Antibiotic resistance in 2015-2016 remained similar as in 2009-2012.
CONCLUSIONS
Low antibiotic resistance was observed among respiratory tract pathogens, except for tetracycline.
Topics: Cattle; Animals; Swine; Anti-Bacterial Agents; Bacteria; Pasteurella multocida; Respiratory Tract Infections; Tetracycline; Respiratory System; Microbial Sensitivity Tests; Cattle Diseases; Drug Resistance, Bacterial
PubMed: 37391360
DOI: 10.1093/jambio/lxad132 -
Veterinary Microbiology Sep 2023The impact of S. suis on Swedish pig production has increased in recent years, and characterization of the strains present in the pig population is needed to aid in...
The impact of S. suis on Swedish pig production has increased in recent years, and characterization of the strains present in the pig population is needed to aid in surveillance and prevention. Therefore, the aim of this study was to identify and characterize differences in the genomes between Swedish S. suis isolates associated with disease and isolates from healthy animals. Isolates categorized as being pathogenic (n = 100) or non-pathogenic (n = 117) were whole-genome sequenced, serotyped in silico, and sequence-typed using traditional MLST and core-genome MLST, and a genome-wide association study was performed to identify virulence-associated genes. In decreasing order, serotypes 2, 1, and 7 were the most common in the pathogenic group, and serotypes 15 and 12 were the most common in the non-pathogenic group. Among the commonly disease-associated sequence types, ST28 and ST25 were identified, whereas ST1 was scarcely found. The majority of isolates belonged to novel sequence types, revealing differences between Swedish isolates and those reported from other countries. The genomes of the pathogenic isolates were on average smaller and less heterogenic as compared to those of the non-pathogenic isolates. Although a majority of the previously published virulence-associated genes included in the study were found in the genomes of both pathogenic and non-pathogenic isolates, several new, significantly virulence-associated genes were identified.
Topics: Swine; Animals; Virulence; Streptococcus suis; Multilocus Sequence Typing; Streptococcal Infections; Sweden; Genome-Wide Association Study; Swine Diseases
PubMed: 37531841
DOI: 10.1016/j.vetmic.2023.109839 -
BMC Biology Feb 2024Ribosomal protein SA (RPSA) of human brain microvascular endothelial cells (HBMECs) can transfer from the cytosol to the cell surface and act as a receptor for some...
BACKGROUND
Ribosomal protein SA (RPSA) of human brain microvascular endothelial cells (HBMECs) can transfer from the cytosol to the cell surface and act as a receptor for some pathogens, including Streptococcus suis serotype 2 (SS2), a zoonotic pathogen causing meningitis in pigs and humans. We previously reported that SS2 virulence factor enolase (ENO) binds to RPSA on the cell surface of HBMECs and induces apoptosis. However, the mechanism that activates RPSA translocation to the cell surface and induces ENO-mediated HBMEC apoptosis is unclear.
RESULTS
Here, we show that RPSA localization and condensation on the host cell surface depend on its internally disordered region (IDR). ENO binds to the IDR of RPSA and promotes its interaction with RPSA and vimentin (VIM), which is significantly suppressed after 1,6-Hexanediol (1,6-Hex, a widely used tool to disrupt phase separation) treatment, indicating that ENO incorporation and thus the concentration of RPSA/VIM complexes via co-condensation. Furthermore, increasing intracellular calcium ions (Ca) in response to SS2 infection further facilitates the liquid-like condensation of RPSA and aggravates ENO-induced HBMEC cell apoptosis.
CONCLUSIONS
Together, our study provides a previously underappreciated molecular mechanism illuminating that ENO-induced RPSA condensation activates the migration of RPSA to the bacterial cell surface and stimulates SS2-infected HBMEC death and, potentially, disease progression. This study offers a fresh avenue for investigation into the mechanism by which other harmful bacteria infect hosts via cell surfaces' RPSA.
Topics: Humans; Animals; Swine; Streptococcus suis; Endothelial Cells; Serogroup; Phosphopyruvate Hydratase; Brain; Apoptosis; Ribosomal Proteins; Streptococcal Infections
PubMed: 38331785
DOI: 10.1186/s12915-024-01835-y -
European Archives of... May 2024This study aimed to explore the diagnostic sensitivity of 3D heavily weighted T2-weighted MRI (T2MRI) and high-resolution computed tomography (HRCT) in patients with...
OBJECTIVES
This study aimed to explore the diagnostic sensitivity of 3D heavily weighted T2-weighted MRI (T2MRI) and high-resolution computed tomography (HRCT) in patients with cochlear fibrosis associated with Streptococcus suis (S. suis) meningitis and the practicality of Cochlear implantation (CI) treatments.
METHODS
Between January 2020 and December 2022, we enrolled four patients with rare cochlear S. suis meningitis with associated hearing loss despite aggressive or non-aggressive follow-up antibiotic treatment. Clinical imaging data, surgical performances and post-surgical-electrode impedance were evaluated.
RESULTS
Combined with HRCT and T2MRI, the cochlea had varying degrees of fibrosis and ossification in different cases. However, the electrodes were successfully and wholly inserted after intraoperative removal of the ossified and fibrotic foci. Post-surgical electrode impedance values of MP1 + 2 mode were normal in all 4 cases at initial activation.
CONCLUSION
In patients with S. suis meningitis and associated cochlear fibrosis, T2MRI examination of the inner ear was more sensitive than HRCT. This research highlights the feasibility of CI treatment in S. suis meningitis patients with severe cochlear fibrosis.
PubMed: 38758241
DOI: 10.1007/s00405-024-08730-w -
Archives of Microbiology Nov 2023To address the growing health threat posed by drug-resistant pathogenic microorganisms, the development of novel antimicrobial medications with multiple mechanisms of...
To address the growing health threat posed by drug-resistant pathogenic microorganisms, the development of novel antimicrobial medications with multiple mechanisms of action is in urgent demand. With traditional antibacterial drug resources challenging to push forward, developing new antibacterial drugs has become a hot spot in biomedical research. In this study, we tested the antibacterial activity of 119 phenanthridine derivatives via the antibacterial assay and obtained 5 candidates. The cytotoxicity assay showed one phenanthridine derivative, HCK20, was safe for mammalian cells below 125 µM. HCK20 was verified to possess significant antibacterial activity to Streptococcus spp., such as Streptococcus pneumoniae, Streptococcus agalactiae, Streptococcus suis, Streptococcus dysgalactiae, and Streptococcus equi with MICs ranging from 15 to 60 µM. Furthermore, we found that HCK20 probably achieved its bacterial inhibition by influencing the permeability of bacterial cell walls via interacting with Streptococcal penicillin-binding proteins (PBPs). Our results suggest that this phenanthridine derivative, HCK20, has great potential to become a novel antibacterial agent that can be a potent treatment for streptococcal infections.
Topics: Animals; Phenanthrenes; Streptococcus suis; Anti-Bacterial Agents; Phenanthridines; Mammals
PubMed: 37930433
DOI: 10.1007/s00203-023-03705-7 -
Pathogens (Basel, Switzerland) Oct 2023The presence of bacterial pathogens such as spp., spp., , , spp., spp., and not only hampers pig production but also carries significant zoonotic implications. The... (Review)
Review
The presence of bacterial pathogens such as spp., spp., , , spp., spp., and not only hampers pig production but also carries significant zoonotic implications. The present study aims to conduct a comprehensive meta-analysis spanning over 13 years (2010-2023) to ascertain the prevalence of these zoonotic bacterial pathogens in Indian pig populations. The study seeks to synthesize data from diverse geographic regions within India and underscores the relevance of the One Health framework. A systematic search of electronic databases was meticulously performed. Inclusion criteria encompassed studies detailing zoonotic bacterial pathogen prevalence in pigs within India during the specified timeframe. Pertinent information including authors, publication year, geographical location, sampling techniques, sample sizes, and pathogen-positive case counts were meticulously extracted. The meta-analysis of zoonotic bacterial pathogens in Indian pig populations (2010-2023) unveiled varying prevalence rates: 9% spp., 22% spp., 19% , 12% , 10% spp. and , and 24% spp. The application of random effects further revealed additional variability: 6% spp., 23% spp., 24% , 14% , 10% spp. and , and 35% spp. Notably, the observed heterogeneity (I) varied significantly from 87% to 99%. The meta-analysis findings underscore the pervasive nature of these diseases throughout India's pig populations, accentuating the substantial impact of these pathogens on pig health and the potential for zoonotic transmission. The present study reinforces the importance of the adoption of a comprehensive One Health approach that acknowledges the intricate interplay between animal, human and environmental health.
PubMed: 37887783
DOI: 10.3390/pathogens12101266 -
Microorganisms Sep 2023() presents a serious threat to the pig industry as well as food safety and public health. Although several LAMP assays have been developed for the identification of ,...
() presents a serious threat to the pig industry as well as food safety and public health. Although several LAMP assays have been developed for the identification of , no universal assay is so far available for the field-suitable examination of clinical pig specimens. Based on the housekeeping gene, a new loop-mediated isothermal amplification (LAMP) assay was developed and validated for the detection of in the brain and joints of pigs. For this LAMP assay, two different methods for the extraction of DNA from brain and joint swabs were compared. Using the LPTV boiling method, the detection limit of LAMP was 1.08 CFU/reaction, while the detection limit was 53.8 CFU/reaction using a commercial DNA extraction kit. The detection limits of -LAMP in combination with the LPTV boiling method were 10-10 CFU/swab in the presence of brain tissue and 10-10 CFU/swab in the presence of joint tissue. The diagnostic quality criteria of LAMP were determined by the examination of 49 brain swabs and 34 joint swabs obtained during routine diagnostic necropsies. Applying the LPTV boiling method to brain swabs, the sensitivity, specificity, and positive and negative predictive values of -LAMP were 88.0, 95.8, 95.7, and 88.5% using cultural investigation as a reference method, and 76.7, 100, 100, and 73.1% using real-time PCR as a reference method. Based on these results, the -LAMP assay combined with the LPTV boiling method is suitable for rapid detection of from brain swabs.
PubMed: 37894105
DOI: 10.3390/microorganisms11102447 -
Emerging Infectious Diseases Mar 2024Streptococcus suis, a zoonotic bacterial pathogen circulated through swine, can cause severe infections in humans. Because human S. suis infections are not notifiable in... (Review)
Review
Streptococcus suis, a zoonotic bacterial pathogen circulated through swine, can cause severe infections in humans. Because human S. suis infections are not notifiable in most countries, incidence is underestimated. We aimed to increase insight into the molecular epidemiology of human S. suis infections in Europe. To procure data, we surveyed 7 reference laboratories and performed a systematic review of the scientific literature. We identified 236 cases of human S. suis infection from those sources and an additional 87 by scanning gray literature. We performed whole-genome sequencing to type 46 zoonotic S. suis isolates and combined them with 28 publicly available genomes in a core-genome phylogeny. Clonal complex (CC) 1 isolates accounted for 87% of typed human infections; CC20, CC25, CC87, and CC94 also caused infections. Emergence of diverse zoonotic clades and notable severity of illness in humans support classifying S. suis infection as a notifiable condition.
Topics: Humans; Animals; Swine; Molecular Epidemiology; Streptococcus suis; Europe; Phylogeny; Whole Genome Sequencing
PubMed: 38407169
DOI: 10.3201/eid3003.230348