-
International Journal of Biological... May 2024Streptococcus suis (S. suis) is a significant zoonotic microorganism that causes a severe illness in both pigs and humans and is characterized by severe meningitis and...
Streptococcus suis (S. suis) is a significant zoonotic microorganism that causes a severe illness in both pigs and humans and is characterized by severe meningitis and septicemia. Suilysin (SLY), which is secreted by S. suis, plays a crucial role as a virulence factor in the disease. To date, the interaction between SLY and host cells is not fully understood. In this study, we identified the interacting proteins between SLY and human brain microvascular endothelial cells (HBMECs) using the TurboID-mediated proximity labeling method. 251 unique proteins were identified in TurboID-SLY treated group, of which six plasma membrane proteins including ARF6, GRK6, EPB41L5, DSC1, TJP2, and PNN were identified. We found that the proteins capable of interacting with SLY are ARF6 and PNN. Subsequent investigations revealed that ARF6 substantially increased the invasive ability of S. suis in HBMECs. Furthermore, ARF6 promoted SLY-induced the activation of p38 MAPK signaling pathway in HBMECs. Moreover, ARF6 promoted the apoptosis in HBMECs through the activation of p38 MAPK signaling pathway induced by SLY. Finally, we confirmed that ARF6 could increase the virulence of SLY in C57BL/6 mice. These findings offer valuable insights that contribute to a deeper understanding of the pathogenic mechanism of SLY.
Topics: Streptococcus suis; Humans; Animals; Apoptosis; ADP-Ribosylation Factor 6; Mice; ADP-Ribosylation Factors; Endothelial Cells; Hemolysin Proteins; p38 Mitogen-Activated Protein Kinases; Streptococcal Infections; Virulence; Brain
PubMed: 38663699
DOI: 10.1016/j.ijbiomac.2024.131839 -
Veterinary Microbiology Sep 2023Bordetella bronchiseptica and Streptococcus suis are widely distributed swine pathogens. B. bronchiseptica is a primary pathogen and causes atrophic rhinitis and...
Bordetella bronchiseptica and Streptococcus suis are widely distributed swine pathogens. B. bronchiseptica is a primary pathogen and causes atrophic rhinitis and bronchopneumonia. S. suis is a contributing agent to porcine respiratory disease complex and causes systemic diseases including arthritis, meningitis, polyserositis, and septicemia. Colonization with B. bronchiseptica has been associated with increased colonization by other pathogenic bacteria and increased disease severity with viral and bacterial pathogens. It has also been reported to predispose cesarean derived, colostrum deprived (CDCD) piglets to S. suis systemic disease. Here, we evaluated the role of B. bronchiseptica colonization on S. suis colonization, dissemination, and disease in one study using conventional pigs and another using CDCD pigs. Pigs were challenged with S. suis, B. bronchiseptica, or B. bronchiseptica followed by S. suis. Incidence of S. suis disease was not increased in either study for animals pre-inoculated with B. bronchiseptica. Nasal colonization with S. suis was increased in coinfected animals, while B. bronchiseptica was similar between mono- and co-infected animals. Although increased S. suis disease was not seen in coinfected pigs, there is evidence that B. bronchiseptica can increase colonization with S. suis, which may contribute to enhanced disease when animals are stressed or immunocompromised.
Topics: Pregnancy; Female; Animals; Swine; Bordetella bronchiseptica; Streptococcus suis; Swine Diseases; Bordetella Infections; Nose; Bacteria
PubMed: 37542929
DOI: 10.1016/j.vetmic.2023.109841 -
Vaccines Mar 2024is an important zoonotic pathogen that mainly causes meningitis, septicemia, and arthritis. Due to the limited cross-protection between numerous serotypes, the existing...
is an important zoonotic pathogen that mainly causes meningitis, septicemia, and arthritis. Due to the limited cross-protection between numerous serotypes, the existing inactive vaccines in clinical use fail to offer sufficient protection. In this study, a gene deletion-attenuated strain Δ-m (P353L)-SC-19 was constructed by deleting and genes from the epidemic strain SC-19 with a mutation of SLY (P353L). The safety of Δ-m (P353L)-SC-19 was confirmed in both in vitro and in vivo experiments. We further demonstrated that immunization with Δ-m (P353L)-SC-19 induced significant cellular immunity and humoral immunity in mice and protected against infections caused by type 2 strain SC-19 (100% protection) and type 9 strain S29 (50% protection), while also preventing meningitis induced by S29. This study highlights the potential of using CPS-deficient strains to achieve cross-protection against different serotypes and develop a promising universal live vaccine.
PubMed: 38543917
DOI: 10.3390/vaccines12030283 -
Journal of Microbiological Methods Nov 2023A mismatch amplification mutation assay (MAMA)-PCR, which detects a single-nucleotide polymorphism contributed to serological difference between Streptococcus suis...
A mismatch amplification mutation assay (MAMA)-PCR, which detects a single-nucleotide polymorphism contributed to serological difference between Streptococcus suis serotypes 2 and 1/2, is used to discriminate between these serotypes. The present study reports unusual serotype 1/2 isolates untypable by the MAMA-PCR and improvement of the MAMA-PCR for typing such isolates.
Topics: Humans; Animals; Swine; Serogroup; Serotyping; Streptococcus suis; Streptococcal Infections; Polymerase Chain Reaction; Mutation; Swine Diseases
PubMed: 37783232
DOI: 10.1016/j.mimet.2023.106828 -
Applied and Environmental Microbiology Nov 2023To the best of our knowledge, this study reveals a strong correlation between mass spectra pattern and virulence phenotype among for the first time. In order to make...
To the best of our knowledge, this study reveals a strong correlation between mass spectra pattern and virulence phenotype among for the first time. In order to make the findings applicable and to excavate the intrinsic information in the spectra, the classifiers based on the machine learning algorithms were established, and RF (Random Forest)-based models have achieved an accuracy of over 90%. Overall, this study will pave the way for virulent SS2 ( serotype 2) rapid detection, and the important findings on the association between genotype and mass spectrum may provide a new idea for the genotype-dependent detection of specific pathogens.
Topics: Humans; Virulence; Streptococcus suis; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Serogroup; Streptococcal Infections; Machine Learning
PubMed: 37861326
DOI: 10.1128/aem.01284-23 -
Frontiers in Microbiology 2024serotype 2 (SS2) is a Gram-positive bacterium. It is a common and significant pathogen in pigs and a common cause of zoonotic meningitis in humans. It can lead to...
serotype 2 (SS2) is a Gram-positive bacterium. It is a common and significant pathogen in pigs and a common cause of zoonotic meningitis in humans. It can lead to sepsis, endocarditis, arthritis, and pneumonia. If not diagnosed and treated promptly, it has a high mortality rate. The pan-genome of SS2 is open, and with an increasing number of genes, the core genome and accessory genome may exhibit more pronounced differences. Due to the diversity of SS2, the genes related to its virulence and resistance are still unclear. In this study, a strain of SS2 was isolated from a pig farm in Sichuan Province, China, and subjected to whole-genome sequencing and characterization. Subsequently, we conducted a Pan-Genome-Wide Association Study (Pan-GWAS) on 230 strains of SS2. Our analysis indicates that the core genome is composed of 1,458 genes related to the basic life processes of the bacterium. The accessory genome, consisting of 4,337 genes, is highly variable and a major contributor to the genetic diversity of SS2. Furthermore, we identified important virulence and resistance genes in SS2 through pan-GWAS. The virulence genes of SS2 are mainly associated with bacterial adhesion. In addition, resistance genes in the core genome may confer natural resistance of SS2 to fluoroquinolone and glycopeptide antibiotics. This study lays the foundation for further research on the virulence and resistance of SS2, providing potential new drug and vaccine targets against SS2.
PubMed: 38450165
DOI: 10.3389/fmicb.2024.1362316 -
Veterinary Research Feb 2024Streptococcus suis (S. suis) is an important porcine pathogen causing meningitis, arthritis, and septicemia. Serotypes 2 and 14 are the most common zoonotic ones...
Streptococcus suis (S. suis) is an important porcine pathogen causing meningitis, arthritis, and septicemia. Serotypes 2 and 14 are the most common zoonotic ones worldwide, whereas serotypes 2, 9, and 7 are very important in pigs in Europe. To cause invasive infections S. suis needs to enter the bloodstream. Consequently, the immune response in blood represents an important line of defense and bacteremia plays a key role in the pathogenesis of invasive S. suis infections. We investigated the working hypothesis that S. suis strains of the same serotype but different clonal complex (CC) might exhibit substantial differences in the interaction with components of the immune system in porcine blood. The experimental design of this study includes comparative analysis of 8 virulent strains belonging to 4 serotypes with strains of the same serotype being genetically not closely related. Significant differences between two strains of the same serotype but different clonal complex were recorded in the flow cytometric analysis of association with different leukocytes for serotype 9 and 14. Our results demonstrate that the serotype 9 strain of CC94 shows significantly increased association with monocytes and survival in porcine blood of conventional piglets as well as a tendency towards decreased composition of C3 in plasma of these piglets in comparison to the serotype 9 strain of CC16. Correlation analysis of C3 deposition on the bacterial surface and survival in respective blood samples of 8-week-old piglets demonstrated a negative correlation indicating that C3 deposition is a crucial step to limit bacterial survival and proliferation of different S. suis pathotypes in the blood of these piglets. In summary, our results indicate that the capsule composition of a S. suis strain is not alone sufficient to determine association with leukocytes, activation of complement, induction of proinflammatory cytokines, oxidative burst, and bacterial survival in porcine blood. In this study, substantial differences in these host-pathogen interactions were observed between strains of the same serotype. Therefore, a more comprehensive characterization of the field isolates, including at least MLST analysis to determine the sequence type/clonal complex, is recommended.
Topics: Swine; Animals; Streptococcus suis; Monocytes; Multilocus Sequence Typing; Serogroup; Granulocytes; Streptococcal Infections; Swine Diseases
PubMed: 38317258
DOI: 10.1186/s13567-024-01268-z -
Autophagy Jul 2024() represents a major human bacterial pathogen leading to high morbidity and mortality in children and the elderly. Recent research emphasizes the role of extracellular...
() represents a major human bacterial pathogen leading to high morbidity and mortality in children and the elderly. Recent research emphasizes the role of extracellular vesicles (EVs) in bacterial pathogenicity. However, the contribution of EVs (pEVs) to host-microbe interactions has remained unclear. Here, we observed that infections in mice led to severe lung injuries and alveolar epithelial barrier (AEB) dysfunction. Infections of reduced the protein expression of tight junction protein OCLN (occludin) and activated macroautophagy/autophagy in lung tissues of mice and A549 cells. Mechanically, induced autophagosomal degradation of OCLN leading to AEB impairment in the A549 monolayer. released the pEVs that could be internalized by alveolar epithelial cells. Through proteomics, we profiled the cargo proteins inside pEVs and found that these pEVs contained many virulence factors, among which we identified a eukaryotic-like serine-threonine kinase protein StkP. The internalized StkP could induce the phosphorylation of BECN1 (beclin 1) at Ser93 and Ser96 sites, initiating autophagy and resulting in autophagy-dependent OCLN degradation and AEB dysfunction. Finally, the deletion of in completely protected infected mice from death, significantly alleviated OCLN degradation , and largely abolished the AEB disruption caused by pEVs . Overall, our results suggested that pEVs played a crucial role in the spread of virulence factors. The cargo protein StkP in pEVs could communicate with host target proteins and even hijack the BECN1 autophagy initiation pathway, contributing to AEB disruption and bacterial pathogenicity.: AEB: alveolarepithelial barrier; AECs: alveolar epithelial cells; ATG16L1: autophagy related 16 like 1; ATP:adenosine 5'-triphosphate; BafA: bafilomycin A; BBB: blood-brain barrier; CFU: colony-forming unit; co-IP: co-immunoprecipitation; CQ:chloroquine; CTRL: control; DiO: 3,3'-dioctadecylox-acarbocyanineperchlorate; DOX: doxycycline; DTT: dithiothreitol; ECIS: electricalcell-substrate impedance sensing; eGFP: enhanced green fluorescentprotein; erm: erythromycin-resistance expression cassette; Ery: erythromycin; eSTKs: eukaryotic-like serine-threoninekinases; EVs: extracellular vesicles; HA: hemagglutinin; H&E: hematoxylin and eosin; HsLC3B: human LC3B; hpi: hours post-infection; IP: immunoprecipitation; KD: knockdown; KO: knockout; LAMP1: lysosomal associated membrane protein 1; LC/MS: liquid chromatography-mass spectrometry; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MVs: membranevesicles; NC:negative control; NETs:neutrophil extracellular traps; OD: optical density; OMVs: outer membrane vesicles; PBS: phosphate-buffered saline; pEVs: extracellular vesicles; protK: proteinase K; Rapa: rapamycin; RNAi: RNA interference; ; SNF:supernatant fluid; sgRNA: single guide RNA; ; TEER: trans-epithelium electrical resistance; moi: multiplicity ofinfection; TEM:transmission electron microscope; TJproteins: tight junction proteins; TJP1/ZO-1: tight junction protein1; TSA: tryptic soy agar; WB: western blot; WT: wild-type.
Topics: Animals; Extracellular Vesicles; Autophagy; Streptococcus pneumoniae; Humans; A549 Cells; Mice; Alveolar Epithelial Cells; Mice, Inbred C57BL; Beclin-1; Protein Serine-Threonine Kinases; Phosphorylation
PubMed: 38497494
DOI: 10.1080/15548627.2024.2330043 -
Vaccines May 2024() is a Gram-positive bacterium that causes substantial disease in pigs. is also an emerging zoonoses in humans, primarily in Asia, through the consumption of...
() is a Gram-positive bacterium that causes substantial disease in pigs. is also an emerging zoonoses in humans, primarily in Asia, through the consumption of undercooked pork and the handling of infected pig meat as well as carcasses. The complexity of epidemiology, characterized by the presence of multiple bacterial serotypes and strains with diverse sequence types, identifies a critical need for a universal vaccine with the ability to confer cross-protective immunity. Highly conserved immunogenic proteins are generally considered good candidate antigens for subunit universal vaccines. In this study, the cross-protection of the sugar ABC transporter substrate-binding protein (S-ABC), a surface-associated immunogenic protein of , was examined in mice for evaluation as a universal vaccine candidate. S-ABC was shown to be highly conserved, with 97% amino acid sequence identity across 31 strains deposited in GenBank. Recombinantly expressed S-ABC (rS-ABC) was recognized via rabbit sera specific to serotype 2. The immunization of mice with rS-ABC induced antigen-specific antibody responses, as well as IFN-γ and IL-4, in multiple organs, including the lungs. rS-ABC immunization conferred high (87.5% and 100%) protection against challenges with serotypes 2 and 9, demonstrating high cross-protection against these serotypes. Protection, albeit lower (50%), was also observed in mice challenged with serotype 7. These data identify S-ABC as a promising antigenic target within a universal subunit vaccine against .
PubMed: 38793795
DOI: 10.3390/vaccines12050544 -
Ultrasonics Sonochemistry Jan 2024Emodin was extracted from Rheum officinale Baill by ultrasound-assisted extraction (UAE), and ethanol was chosen as the suitable solvent through SEM and molecular...
Emodin was extracted from Rheum officinale Baill by ultrasound-assisted extraction (UAE), and ethanol was chosen as the suitable solvent through SEM and molecular dynamic simulation. Under the optimum conditions (power 541 W, time 23 min, liquid to material ratio 13:1 mL/g, ethanol concentration 83 %) predicted by RSM, the yield of emodin was 2.18 ± 0.11 mg/g. Moreover, ultrasound power and time displayed the significant effects on the extraction process. Extracting dynamics analysis indicated that the extraction process of emodin by UAE conformed to Fick's second diffusion law. The results of antibacterial experiments suggested that emodin can damage cell membrane and inhibit the expression of cps2A, sao, mrp, epf, neu and the hemolytic activity of S. suis. Biolayer interferometry and FT-IR multi-peak fitting assays demonstrated that emodin induced a secondary conformational shift in CcpA. Molecular docking and molecular dynamics confirmed that emodin bound to CcpA through hydrogen bonding (ALA248, GLU249, GLY129 and ASN196) and π-π T-shaped interaction (TYR225 and TYR130), and the mutation of amino acid residues affected the affinity of CcpA to emodin. Therefore, emodin inhibited the sugar utilization of S. suis through binding to CcpA, and CcpA may be a potential target to inhibit the growth of S. suis.
Topics: Emodin; Rheum; Streptococcus suis; Molecular Docking Simulation; Spectroscopy, Fourier Transform Infrared; Anti-Bacterial Agents; Ethanol
PubMed: 38150957
DOI: 10.1016/j.ultsonch.2023.106733