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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: Streptococcus suis; Humans; Male; Meningitis, Bacterial; Streptococcal Infections; Animals; Swine; Anti-Bacterial Agents; Adult; Middle Aged
PubMed: 38683518
DOI: No ID Found -
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 -
Proceedings of the National Academy of... Nov 2023The expansion and intensification of livestock production is predicted to promote the emergence of pathogens. As pathogens sometimes jump between species, this can...
The expansion and intensification of livestock production is predicted to promote the emergence of pathogens. As pathogens sometimes jump between species, this can affect the health of humans as well as livestock. Here, we investigate how livestock microbiota can act as a source of these emerging pathogens through analysis of , a ubiquitous component of the respiratory microbiota of pigs that is also a major cause of disease on pig farms and an important zoonotic pathogen. Combining molecular dating, phylogeography, and comparative genomic analyses of a large collection of isolates, we find that several pathogenic lineages of emerged in the 19th and 20th centuries, during an early period of growth in pig farming. These lineages have since spread between countries and continents, mirroring trade in live pigs. They are distinguished by the presence of three genomic islands with putative roles in metabolism and cell adhesion, and an ongoing reduction in genome size, which may reflect their recent shift to a more pathogenic ecology. Reconstructions of the evolutionary histories of these islands reveal constraints on pathogen emergence that could inform control strategies, with pathogenic lineages consistently emerging from one subpopulation of and acquiring genes through horizontal transfer from other pathogenic lineages. These results shed light on the capacity of the microbiota to rapidly evolve to exploit changes in their host population and suggest that the impact of changes in farming on the pathogenicity and zoonotic potential of is yet to be fully realized.
Topics: Animals; Humans; Swine; Streptococcal Infections; Farms; Swine Diseases; Virulence; Streptococcus suis; Livestock
PubMed: 37963246
DOI: 10.1073/pnas.2307773120 -
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 -
Virulence Dec 2023type 2 (SS2), a major emerging/re-emerging zoonotic pathogen found in humans and pigs, can cause severe clinical infections, and pose public health issues. Our previous...
type 2 (SS2), a major emerging/re-emerging zoonotic pathogen found in humans and pigs, can cause severe clinical infections, and pose public health issues. Our previous studies recognized peptidyl-prolyl isomerase (PrsA) as a critical virulence factor promoting SS2 pathogenicity. PrsA contributed to cell death and operated as a pro-inflammatory effector. However, the molecular pathways through which PrsA contributes to cell death are poorly understood. Here in this study, we prepared the recombinant PrsA protein and found that pyroptosis and necroptosis were involved in cell death stimulated by PrsA. Specific pyroptosis and necroptosis signalling inhibitors could significantly alleviate the fatal effect. Cleaved caspase-1 and IL-1β in pyroptosis with phosphorylated MLKL proteins in necroptosis pathways, respectively, were activated after PrsA stimulation. Truncated protein fragments of enzymatic PPIase domain (PPI), N-terminal (NP), and C-terminal (PC) domains fused with PPIase, were expressed and purified. PrsA flanking - or C-terminal but not enzymatic PPIase domain was found to be critical for PrsA function in inducing cell death and inflammation. Additionally, PrsA protein could be anchored on the cell surface to interact with host cells. However, Toll-like receptor 2 (TLR2) was not implicated in cell death and recognition of PrsA. PAMPs of PrsA could not promote TLR2 activation, and no rescued phenotypes of death were shown in cells blocking of TLR2 receptor or signal-transducing adaptor of MyD88. Overall, these data, for the first time, advanced our perspective on PrsA function and elucidated that PrsA-induced cell death requires its flanking - or C-terminal domain but is dispensable for recognizing TLR2. Further efforts are still needed to explore the precise molecular mechanisms of PrsA-inducing cell death and, therefore, contribution to SS2 pathogenicity.
Topics: Animals; Humans; Cell Death; Peptidylprolyl Isomerase; Pyroptosis; Streptococcus suis; Swine; Toll-Like Receptor 2; Bacterial Proteins; Streptococcal Infections
PubMed: 37641974
DOI: 10.1080/21505594.2023.2249779 -
Translational Animal Science 2023() is an endemic zoonotic pathogen still lacking adequate prevention in pigs. The present case study looked back to the occurrence and consequences of outbreaks in our...
() is an endemic zoonotic pathogen still lacking adequate prevention in pigs. The present case study looked back to the occurrence and consequences of outbreaks in our swine research facilities in search of new metabolic and physiological insight. From a series of outbreaks, a dataset was created including 56 pigs sampled during disease detection based on clinical signs. Pigs suspected with infection were defined as diseased ( = 28) and included pigs defined as neurologically diseased ( = 20) when severe neurological signs (central nervous system dysfunctions, i.e., opisthotonos, ataxia, and generalized tremor) were observed. Another set of 28 pigs included respective pen mates from each case and were defined as control. Representative deaths were confirmed to be caused by Tonsillar swabs were collected and analyzed by quantitative polymerase chain reaction () for total bacteria, total , and serotypes () 2 (and/or 1/2) and 9. Blood and sera were analyzed to quantify blood gases, minerals, and reactive immunoglobulins against current isolates. Data collected included litter sibling associations, birth and weaning body weight (), and average daily gain () 7 d after the disease detection. In general, the disease increased pH, sO and the incidence of alkalosis, but reduced pCO, glucose, Ca, P, Mg, K, and Na in blood/serum compared to control. The SS2 (and/or SS1/2) prevalence was significantly ( < 0.05) increased in neurologically diseased pigs and its relative abundance tended ( < 0.10) to increase in tonsils. In contrast, the relative abundance of total was lower ( > 0.05) in diseased pigs than control pigs. Levels of reactive IgG2 were lower, but IgM were higher ( < 0.03) in neurologically affected pigs compared to control. Furthermore, there was an increased proportion of sibling pigs that were diseased compared to control. In conclusion, our results evidence that naturally affected pigs were associated to average performing pigs without any predisease trait to highlight but a sow/litter effect. Besides, neurologically affected pigs had increased (SS2 and/or 1/2) prevalence and relative abundance, a respiratory alkalosis profile, and mineral loss.
PubMed: 38023423
DOI: 10.1093/tas/txad126 -
Frontiers in Microbiology 2023Diseases caused by the zoonotic pathogen are an extensive economic problem as well as an animal welfare concern for the global swine industry. Previous studies have...
Diseases caused by the zoonotic pathogen are an extensive economic problem as well as an animal welfare concern for the global swine industry. Previous studies have evaluated the genomic diversity and population structure of isolates, however, the majority of these studies utilized isolates obtained from countries other than the U.S. This study applied whole genome sequencing and cgMLST-based typing to evaluate the population structure and genetic relatedness among isolates obtained within the U.S. The established high-resolution phylogenomic framework revealed extensive genomic variation and diversity among the sampled isolates, with isolates from the U.S. and from countries outside the U.S. found interspersed in the phylogeny. isolates obtained within the U.S. did not cluster by state or geographic location, however, isolates with similar serotypes, both obtained from within and outside the U.S., generally clustered together. Average nucleotide identity (ANI) values determined for the genomes were extensively broad, approaching the recommended species demarcation value, and correlated with the phylogenetic group distribution of the cgMLST-based tree. Numerous antimicrobial resistance (AMR) elements were identified among both U.S. and non-U.S. isolates with , , and genes identified as the most prevalent. The , , and genes, historically used as markers for virulence potential, were also observed in the genomes of isolates that grouped together forming a subclade of clonal complex 1 (CC1) isolates. Collectively, the data in this report provides critical information needed to address potential biosurveillance needs and insights into the genetic diversity and population structure of isolates obtained within the U.S.
PubMed: 37808309
DOI: 10.3389/fmicb.2023.1250265 -
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 -
Animals : An Open Access Journal From... Oct 2023( HPS) is a prominent pathogenic bacterium in pig production. Its infection leads to widespread fibrinous inflammation in various pig tissues and organs, often in...
( HPS) is a prominent pathogenic bacterium in pig production. Its infection leads to widespread fibrinous inflammation in various pig tissues and organs, often in conjunction with various respiratory virus infections, and leads to substantial economic losses in the pig industry. Therefore, the rapid diagnosis of this pathogen is of utmost importance. In this study, we used recombinase polymerase amplification (RPA) and clustered regularly interspaced short palindromic repeats (CRISPR) technology to establish a convenient detection and analysis system for that is fast to detect, easy to implement, and accurate to analyze, known as RPA-CRISPR/Cas12a analysis. The process from sample to results can be completed within 1 h with high sensitivity (0.163 pg/μL of DNA template, < 0.05), which is 10 -fold higher than the common PCR method. The specificity test results show that the RPA-CRISPR/Cas12a analysis of did not react with other common pig pathogens, including type II and IX, , , , , and ( < 0.0001). The RPA-CRISPR/Cas12a assay was applied to 15 serotypes of clinical samples through crude extraction of nucleic acid by boiling method, and all of the samples were successfully identified. It greatly reduces the time and cost of nucleic acid extraction. Moreover, the method allows results to be visualized with blue light. The accurate and convenient detection method could be incorporated into a portable format as point-of-care (POC) diagnostics detection for at the field level.
PubMed: 37958075
DOI: 10.3390/ani13213317