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Medicina 2024Streptococcus suis (S. suis) is a globally prevalent swine pathogen, capable of generating infections in humans who were in contact with the animal or its raw meat....
Streptococcus suis (S. suis) is a globally prevalent swine pathogen, capable of generating infections in humans who were in contact with the animal or its raw meat. Clinical manifestations range from asymptomatic cases to systemic involvement, with low mortality, but with the possibility of leaving definitive sequelae such as ataxia and hearing loss. There are few case reports, due to lack of knowledge of the disease and its atypical presentation. The objective of this article is to report the case of a man with an occupational history of contact with pigs, who was admitted for meningitis and in whom the isolation of S. suis was obtained in cerebrospinal fluid and paired blood cultures; He completed antibiotic treatment adjusted to bacterial sensitivity, and was left with mild hearing loss as a consequence.
Topics: Animals; Humans; Male; Anti-Bacterial Agents; Meningitis, Bacterial; Streptococcal Infections; Streptococcus suis; Swine
PubMed: 38683518
DOI: No ID Found -
International Journal of Molecular... Sep 2023is an emerging zoonotic pathogen that can cause fatal diseases such as meningitis and sepsis in pigs and human beings. The overuse of antibiotics is leading to an...
is an emerging zoonotic pathogen that can cause fatal diseases such as meningitis and sepsis in pigs and human beings. The overuse of antibiotics is leading to an increased level of resistance in , and novel antimicrobial agents or anti-virulence agents for the treatment of infections caused by are urgently needed. In the present study, we investigated the antibacterial activity, mode of action and anti-virulence effects of floxuridine against . Floxuridine showed excessive antibacterial activity against both in vivo and in vitro; 4 × MIC of floxuridine could kill within 8 h in a time-kill assay. Meanwhile, floxuridine disrupted the membrane structure and permeability of the cytoplasmic membrane. Molecular docking revealed that floxuridine and SLY can be directly bind to each other. Moreover, floxuridine effectively inhibited the hemolytic capacity and expression levels of the virulence-related genes of . Collectively, these results indicate that the FDA-approved anticancer drug floxuridine is a promising agent and a potential virulence inhibitor against .
PubMed: 37762514
DOI: 10.3390/ijms241814211 -
Methods in Molecular Biology (Clifton,... 2024In the last few decades, molecular techniques and genetic modification have been used in genotype and phenotype studies of S. suis. Genomic modification of S. suis...
In the last few decades, molecular techniques and genetic modification have been used in genotype and phenotype studies of S. suis. Genomic modification of S. suis requires DNA acquisition and its stable insertion into the chromosome by allelic exchange. In this chapter, we described two techniques for the preparation of genomic constructs (cloning and overlapping extension PCR) and for DNA uptake (electroporation and transformation). The protocols are accompanied with examples. All described protocols were successful on our hands with the reference S. suis strain P1/7.
Topics: Electroporation; Cloning, Molecular; Polymerase Chain Reaction
PubMed: 38884909
DOI: 10.1007/978-1-0716-3898-9_4 -
Virulence Dec 2023is a bacterium that can cause infections in pigs and humans. Although oxidative stress is common occurrence during bacterial growth and infection, the regulation...
is a bacterium that can cause infections in pigs and humans. Although oxidative stress is common occurrence during bacterial growth and infection, the regulation networks of under oxidative stress remain poorly understood. To address this, we utilized RNA-Seq to reveal the transcriptional landscape of in response to HO stress. We identified novel genes responsible for resistance to oxidative stress, including those involved in DNA repair or protection, and essential for the biosynthesis of amino acids and nucleic acids. In addition, we found that a novel aquaporin, Aagp, belonging to atypical aquaglyceroporins and widely distributed in diverse serotypes, plays a crucial role during HO stress. By performing oxidative stress assays and measuring the intracellular HO concentrations of the wild-type strain and mutants during HO stress, we found that Aagp facilitated HO efflux. Additionally, we found that Aagp might be involved in glycerol transport, as shown by the growth inhibition and HO production in the presence of glycerol. Mice infection experiments indicated that Aagp contributed to virulence. This study contributes to understanding the mechanism of oxidative stress response, pathogenesis, and the function of aquaporins in prokaryotes.
Topics: Humans; Animals; Mice; Swine; Hydrogen Peroxide; Streptococcus suis; Glycerol; Virulence; Aquaporins
PubMed: 37621097
DOI: 10.1080/21505594.2023.2249789 -
Microbial Pathogenesis Aug 2023Streptococcus suis (S. suis) regulates biofilm formation through LuxS/AI-2 quorum sensing system, increasing drug resistance and exacerbating infection. The...
Streptococcus suis (S. suis) regulates biofilm formation through LuxS/AI-2 quorum sensing system, increasing drug resistance and exacerbating infection. The anti-hyperglycaemic agent metformin has anti-bacterial and anti-biofilm activities. This study aimed to investigate the anti-biofilm and anti-quorum sensing activity of metformin in S. suis. We first determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of metformin on S. suis. The results indicated that metformin showed no obvious inhibitory or bactericidal effect. Crystal violet staining showed that metformin significantly inhibited the formation of S. suis biofilm at sub-MIC concentration, which was also confirmed by scanning electron microscopy. Then, we quantified the AI-2 signal molecules in S. suis, and the results showed that metformin had a significant inhibitory effect on the production of AI-2 signal in S. suis. Inhibition of enzyme activity and molecular docking experiments showed that metformin has a significant binding activity to LuxS protein. In addition, qRT-PCR results showed that metformin significantly down-regulated the expression of AI-2 synthesis-related genes luxS and pfs, and adhesion-related genes luxS, pfs, gapdh, sly, fbps, and ef. Western blotting also showed that metformin significantly reduced the expression of LuxS protein. Our study suggests that metformin seems to be a suitable candidate for the inhibition of S. suis LuxS/AI-2 QS system and prevention of biofilm formation, which provided a new idea for the prevention and control of S. suis.
Topics: Streptococcus suis; Molecular Docking Simulation; Homoserine; Bacterial Proteins; Quorum Sensing; Biofilms; Carbon-Sulfur Lyases; Lactones
PubMed: 37263449
DOI: 10.1016/j.micpath.2023.106183 -
Methods in Molecular Biology (Clifton,... 2024Streptococcus suis is a bacterial pathogen that can cause significant economic losses in the swine industry due to high morbidity and mortality rates in infected...
Streptococcus suis is a bacterial pathogen that can cause significant economic losses in the swine industry due to high morbidity and mortality rates in infected animals. Vaccination with bacterins, which consist of inactivated bacteria and adjuvants to enhance the pig's immune response, is an effective approach to control S. suis infections in piglets. Here we provide a description of S. suis bacterins and the methods for vaccine preparation. Moreover, this chapter also describes the addition of recombinant Sao (rSao-L) protein to the S. suis bacterin, aiming to enhance the efficacy of the bacterins against S. suis in piglets. Furthermore, the methods for evaluating the immune response elicited by the bacterins are also covered in this chapter.
Topics: Animals; Swine; Streptococcus suis; Streptococcal Infections; Swine Diseases; Vaccination; Bacterial Vaccines; Adjuvants, Immunologic; Antibodies, Bacterial; Recombinant Proteins; Streptococcal Vaccines
PubMed: 38884916
DOI: 10.1007/978-1-0716-3898-9_11 -
Canadian Journal of Veterinary Research... Oct 2023and are ubiquitous colonizers of swine tonsils that can cause systemic disease and death, under undefined conditions. It is not known, however, whether these 2 species...
and are ubiquitous colonizers of swine tonsils that can cause systemic disease and death, under undefined conditions. It is not known, however, whether these 2 species interact during initial infection. To investigate whether such interactions occur, the objective of this study was to assess phenotypic differences between mono-and co-cultures of and when representative strains with different virulence potential were co-cultured In cross-streak screening experiments, some (GP) serovar strains (GP3, GP4, GP5) exhibited altered morphology with some (SS) serovar strains, such as SS2, but not with SS1. Co-culture with GP5 reduced hemolytic activity of SS1, but not of SS2. Although both SS strains outgrew GP isolates in biofilm co-cultures, strain type affected the number of planktonic or sessile cells in co-culture biofilms. Numbers of sessile SS1 increased in co-cultures, but not of GP3. Both planktonic and sessile SS2 increased in co-culture, whereas GP5 decreased. Sessile SS1 increased, but planktonic GP5 decreased in co-culture and planktonic SS2 increased, but sessile GP3 decreased when grown together. The SS2 strain had a competitive advantage over GP3 during mid-exponential co-culture in broth. is predicted to use more unique carbon sources, suggesting that outcompetes in growth and nutrient consumption. This work provides direction for future studies of phenotypic and genotypic interactions between these and other swine tonsil co-colonizers.
Topics: Animals; Swine; Streptococcus suis; Coculture Techniques; Serogroup; Virulence; Genotype; Swine Diseases; Streptococcal Infections
PubMed: 37790267
DOI: No ID Found -
Emerging Microbes & Infections Dec 2024is a major bacterial pathogen in pigs and an emerging zoonotic pathogen. Different serotypes exhibit diverse characteristics in population structure and pathogenicity....
is a major bacterial pathogen in pigs and an emerging zoonotic pathogen. Different serotypes exhibit diverse characteristics in population structure and pathogenicity. Surveillance data highlight the significance of serotype 4 (SS4) in swine streptococcusis, a pathotype causing human infections. However, except for a few epidemiologic studies, the information on SS4 remains limited. In this study, we investigated the population structure, pathogenicity, and antimicrobial characteristics of SS4 based on 126 isolates, including one from a patient with septicemia. We discovered significant diversities within this population, clustering into six minimum core genome (MCG) groups (1, 2, 3, 4, 7-2, and 7-3) and five lineages. Two main clonal complexes (CCs), CC17 and CC94, belong to MCG groups 1 and 3, respectively. Numerous important putative virulence-associated genes are present in these two MCG groups, and 35.00% (7/20) of pig isolates from CC17, CC94, and CC839 (also belonging to MCG group 3) were highly virulent (mortality rate ≥ 80%) in zebrafish and mice, similar to the human isolate ID36054. Cytotoxicity assays showed that the human and pig isolates of SS4 strains exhibit significant cytotoxicity to human cells. Antimicrobial susceptibility testing showed that 95.83% of strains isolated from our labs were classified as multidrug-resistant. Prophages were identified as the primary vehicle for antibiotic resistance genes. Our study demonstrates the public health threat posed by SS4, expanding the understanding of SS4 population structure and pathogenicity characteristics and providing valuable information for its surveillance and prevention.
Topics: Streptococcus suis; Animals; Swine; Humans; Streptococcal Infections; Serogroup; Swine Diseases; Virulence; Mice; Genome, Bacterial; Zebrafish; Anti-Bacterial Agents; Phylogeny; Microbial Sensitivity Tests; Virulence Factors
PubMed: 38703011
DOI: 10.1080/22221751.2024.2352435 -
Methods in Molecular Biology (Clifton,... 2024Streptococcus suis is a swine bacterial pathogen that predominantly causes disease in weaned piglets characterized by swelling of joints, arthritis, septicemia,...
Streptococcus suis is a swine bacterial pathogen that predominantly causes disease in weaned piglets characterized by swelling of joints, arthritis, septicemia, meningitis, and sudden death. Intravenous, intramuscular, intraperitoneal, and intranasal infection models were developed to study the bacterial pathogenicity and efficacy of vaccines and various therapeutics. The selection of the appropriate infection model is a critical step in any study, as it may impact the outcomes of the study. Here we describe a method for infecting weaned piglets with S. suis using intraperitoneal route as a reliable, consistent, and reproducible animal model to evaluate vaccine protection against systemic bacterial infection.
Topics: Animals; Swine; Disease Models, Animal; Streptococcus suis; Streptococcal Infections; Swine Diseases; Injections, Intraperitoneal
PubMed: 38884914
DOI: 10.1007/978-1-0716-3898-9_9 -
Microorganisms Apr 2024() is a zoonotic pathogen capable of causing severe diseases in humans and pigs, including meningitis, sepsis, polyserositis, arthritis, and endocarditis. This study...
() is a zoonotic pathogen capable of causing severe diseases in humans and pigs, including meningitis, sepsis, polyserositis, arthritis, and endocarditis. This study aimed to investigate the biological characteristics of 19 strains of isolated from diseased pigs in Hubei Province between 2021 and 2023. Through bioinformatics analysis, we investigated the serotype, MLST, pan-genome characteristics, SNP, AMR, and ICE of the 19 isolates. Among the 19 strains, ten serotypes were identified, and serotype 9 was the most prevalent (21.05%). Ten new alleles and nine new sequence types (STs) were discovered, with ST28 and ST243 emerging as the predominant STs. The results of the pan-genomic analysis of indicate that there are 943 core genes, 2259 shell genes, and 5663 cloud genes. Through SNP evolutionary analysis, we identified a strong genetic similarity between SS31 and the reference genome P1/7. The analysis of antibiotic resistance genes revealed widespread presence of (B) and (O) genes among 19 strains of . This association may be linked to the high resistance of to lincosamides, macrolides, and tetracyclines. Integrative and conjugative elements (ICEs) and integrative and mobilizable elements (IMEs) were identified in 16 strains, with a carriage rate of 84.21%, and resistance genes were identified within the ICE/IME elements of 8 strains. Antimicrobial susceptibility testing revealed that all strains showed sensitivity to vancomycin and lincomycin but resistance to tilmicosin, tiamulin, amoxicillin, and doxycycline. This study contributes to our understanding of the genomic diversity of in Hubei Province of China, providing essential data for the comprehensive prevention and control of infections in China.
PubMed: 38792744
DOI: 10.3390/microorganisms12050917