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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 -
BMC Veterinary Research Jul 2023Streptococcus suis (S. suis) is a Gram-positive bacteria that infects pigs causing meningitis, arthritis, pneumonia, or endocarditis. This increases the mortality in pig...
BACKGROUND
Streptococcus suis (S. suis) is a Gram-positive bacteria that infects pigs causing meningitis, arthritis, pneumonia, or endocarditis. This increases the mortality in pig farms deriving in severe economic losses. The use of saliva as a diagnostic fluid has various advantages compared to blood, especially in pigs. In this study, it was hypothesized that saliva could reflect changes in different biomarkers related to stress, inflammation, redox status, and muscle damage in pigs with S. suis infection and that changes in these biomarkers could be related to the severity of the disease.
RESULTS
A total of 56 growing pigs from a farm were selected as infected pigs (n = 28) and healthy pigs (n = 28). Results showed increases in biomarkers related to stress (alpha-amylase and oxytocin), inflammation (haptoglobin, inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4), total protein, S100A8-A9 and S100A12), redox status (advanced oxidation protein producs (AOPP)) and muscle damage (creatine kinase (CK), CK-MB, troponin I, lactate, aspartate aminotransferase, and lactate dehydrogenase). An increase in adenosine deaminase (ADA), procalcitonin, and aldolase in infected animals were also observed, as previously described. The grade of severity of the disease indicated a significant positive correlation with total protein concentrations, aspartate aminotransferase, aldolase, and AOPP.
CONCLUSIONS
This report revealed that S. suis infection caused variations in analytes related to stress, inflammation, redox status, and muscle damage in the saliva of pigs and these can be considered potential biomarkers for this disease.
Topics: Swine; Animals; Streptococcus suis; Advanced Oxidation Protein Products; Swine Diseases; Inflammation; Streptococcal Infections; Biomarkers; Aldehyde-Lyases; Muscles
PubMed: 37525237
DOI: 10.1186/s12917-023-03650-z -
Talanta Jan 2024Streptococcus suis serotype 2 is an economically important zoonotic pathogen that causes septicemia, arthritis, and meningitis in pigs and humans. S. suis serotype 2 is...
Streptococcus suis serotype 2 is an economically important zoonotic pathogen that causes septicemia, arthritis, and meningitis in pigs and humans. S. suis serotype 2 is responsible for substantial economic losses to the swine industry and poses a serious threat to public health, and accurate and rapid detection is important for the prevention and control of epidemic disease. In this study, we developed a high-fidelity detection and serotyping platform for S. suis serotype 2 based on recombinase polymerase amplification (RPA) and a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a system called Cards-SSJ/K. Cards-SSJ had a detection limit of 10 CFU, takes <60 min, and no cross-reaction was found with other S. suis serotypes, closely related Streptococcus spp., or common pig pathogens, and Cards-SSK could differentiate serotype 2 from serotype 1/2. Results from Cards-SSJ and qPCR were equivalent in detecting S. suis serotype 2 in tissue samples. Analysis indicated that despite a relatively high reagent cost compared to PCR and qPCR, Cards-SSJ was less time-consuming and had low requirements for equipment and personnel. Thus, it is an excellent method for point-of-care detection for S. suis serotype 2.
Topics: Humans; Swine; Animals; Serotyping; Serogroup; Streptococcus suis; CRISPR-Cas Systems; Streptococcal Infections
PubMed: 37734291
DOI: 10.1016/j.talanta.2023.125202 -
International Journal of Antimicrobial... Dec 2023Streptococcus suis is an important zoonotic pathogen that often causes biofilm-associated infection. Bacterial biofilm-dependent infection is associated with enhanced...
BACKGROUND
Streptococcus suis is an important zoonotic pathogen that often causes biofilm-associated infection. Bacterial biofilm-dependent infection is associated with enhanced drug resistance, making it difficult to eradicate. Novel therapeutic approaches are required urgently to treat infections associated with S. suis biofilm. This study aimed to investigate the effects and mechanisms of methyl anthranilate (MA) on S. suis biofilm.
METHODS
The effect of MA on S. suis biofilm was determined using the crystal violet method, and the microstructure of the biofilm was observed by electron microscopy. The effects on capsular polysaccharides were determined using the phenol-sulphuric acid method and high-performance liquid chromatography. Adhesion and antiphagocytosis properties of S. suis were detected via cell assays. Molecular docking, molecular dynamics simulation and enzyme activity inhibition assays were used to further explore the effect of MA on AI-2 quorum sensing (QS) of S. suis. Finally, the therapeutic effect of MA was investigated using a mouse infection model.
RESULTS
MA destroyed the structure of S. suis biofilm, hindered biofilm formation, and reduced the synthesis of capsular polysaccharides significantly, which further weakened the adhesion and antiphagocytosis ability of S. suis. MA had a docking effect and binding site (SER76 and ASP197) similar to S-adenosylhomocysteine (SAH). Further analysis showed that MA competitively bound 5'-methyladenosine/S-adenosine homocysteine nucleosidase with SAH to interfere with AI-2 QS. In a mouse model, MA reduced the bacterial burden and inflammatory infiltrates effectively.
CONCLUSION
This study revealed the antibiofilm effects of MA, and highlighted its potential as a QS inhibitor against S. suis infection.
Topics: Humans; Streptococcus suis; Molecular Docking Simulation; Biofilms; Polysaccharides; Streptococcal Infections
PubMed: 37788717
DOI: 10.1016/j.ijantimicag.2023.106996 -
Frontiers in Cellular and Infection... 2023is an encapsulated bacterium causing severe diseases in swine. Here, we compared the protective properties of the capsular polysaccharide (CPS) of different serotypes...
is an encapsulated bacterium causing severe diseases in swine. Here, we compared the protective properties of the capsular polysaccharide (CPS) of different serotypes by using serotype-switched mutants in a mouse model of infection. CPS structure influenced bacterial survival in mice, antibody binding, and antibody-mediated bacterial killing. The CPS of serotypes 3, 4 and 14 allowed more antibody binding and bacterial elimination than the CPS of serotypes 2, 7 and 9. Results suggest that the different CPS structures of provide varying levels of protection by influencing antigen availability and elimination by the host immune system.
Topics: Animals; Mice; Swine; Polysaccharides, Bacterial; Streptococcus suis; Bacterial Capsules; Serogroup; Antibodies; Streptococcal Infections; Antibodies, Bacterial
PubMed: 37545852
DOI: 10.3389/fcimb.2023.1228496 -
Journal of Applied Microbiology Nov 2023Swine respiratory disease (SRD) is a major disease complex in pigs that causes severe economic losses. SRD is associated with several intrinsic and extrinsic factors...
AIMS
Swine respiratory disease (SRD) is a major disease complex in pigs that causes severe economic losses. SRD is associated with several intrinsic and extrinsic factors such as host health status, viruses, bacteria, and environmental factors. Particularly, it is known that many pathogens are associated with SRD to date, but most of the test to detect those pathogens can be normally investigated only one pathogen while taking time and labor. Therefore, it is desirable to develop rapidly and efficiently detectable methods those pathogens to minimize the damage caused by SRD.
METHODS AND RESULTS
We designed a multiplex real-time RT-PCR (RT-qPCR) system to diagnose simultaneously 16 pathogens, including nine viruses and seven bacteria associated with SRD, on the basis of single qPCR and RT-qPCR assays reported in previous studies. Multiplex RT-qPCR system we designed had the same ability to single RT-qPCR without significant differences in detection sensitivity for all target pathogens at minimum to maximum genomic levels. Moreover, the primers and probes used in this system had highly specificity because the sets had not been detected pathogens other than the target and its taxonomically related pathogens. Furthermore, our data demonstrated that this system would be useful to detect a causative pathogen in the diagnosis using oral fluid from healthy pigs and lung tissue from pigs with respiratory disorders collected in the field.
CONCLUSIONS
The rapid detection of infected animals from the herd using our system will contribute to infection control and prompt treatment in the field.
Topics: Animals; Swine; Reverse Transcriptase Polymerase Chain Reaction; Swine Diseases; Viruses; Lung; Multiplex Polymerase Chain Reaction; Bacteria
PubMed: 37951290
DOI: 10.1093/jambio/lxad263 -
Scientific Reports Dec 2023This study aimed to determine the presence and characteristics of locally circulating strains of Streptococcus suis, the most important streptococcal pathogen in swine....
This study aimed to determine the presence and characteristics of locally circulating strains of Streptococcus suis, the most important streptococcal pathogen in swine. Oral swab samples were collected from pigs from 664 representative smallhold farms across nine provinces in the Philippines. Isolates were identified and characterized using PCR assays. The study revealed an isolation rate of 15.8% (105/664, 95% CI: 13.0-18.6) among the sampled farms. Two hundred sixty-nine (269) S. suis isolates were recovered from 119 unique samples. Serotype 31 was the most prevalent (50/269, 95% CI: 13.9-23.2) among the other serotypes identified: 5, 6, 8, 9, 10, 11, 15, 16, 17, 21, 27, 28, and 29. The detection of the three 'classical' S. suis virulence-associated genes showed that 90.7% (244/269, 95% CI: 87.2-94.2) were mrp/epf/sly Multilocus sequence typing (MLST) analysis further revealed 70 novel sequence types (STs). Notably, several local isolates belonging to these novel STs formed clonal complexes (CC) with S. suis strains recovered from Spain and USA, which are major pork-exporting countries to the Philippines. This study functionally marks the national baseline knowledge of S. suis in Philippines.
Topics: Swine; Animals; Multilocus Sequence Typing; Streptococcus suis; Philippines; Farms; Streptococcal Infections; Genotype; Swine Diseases; Genetic Variation
PubMed: 38040767
DOI: 10.1038/s41598-023-48406-9 -
PloS One 2023Streptococcus suis is a zoonotic pathogen that causes invasive infections in humans and pigs. Herein, we performed genomic analysis of seven S. suis serotype 4 strains...
Streptococcus suis is a zoonotic pathogen that causes invasive infections in humans and pigs. Herein, we performed genomic analysis of seven S. suis serotype 4 strains belonging to clonal complex (CC) 94 that were recovered from a human patient or from diseased and clinically healthy pigs. Genomic exploration and comparisons, as well as in vitro cytotoxicity tests, indicated that S. suis CC94 serotype 4 strains are potentially virulent. Genomic analysis revealed that all seven strains clustered within minimum core genome group 3 (MCG-3) and had a high number of virulence-associated genes similar to those of virulent serotype 2 strains. Cytotoxicity assays showed that both the human lung adenocarcinoma cell line and HeLa cells rapidly lost viability following incubation for 4 h with the strains at a concentration of 106 bacterial cells. The human serotype 4 strain (ID36054) decreased cell viability profoundly and similarly to the control serotype 2 strain P1/7. In addition, strain ST1689 (ID34572), isolated from a clinically healthy pig, presented similar behaviour in an adenocarcinoma cell line and HeLa cells. The antimicrobial resistance genes tet(O) and ermB that confer resistance to tetracyclines, macrolides, and lincosamides were commonly found in the strains. However, aminoglycoside and streptothricin resistance genes were found only in certain strains in this study. Our results indicate that S. suis CC94 serotype 4 strains are potentially pathogenic and virulent and should be monitored.
Topics: Swine; Humans; Animals; Serogroup; Virulence; Streptococcus suis; HeLa Cells; Genomics; Anti-Bacterial Agents; Streptococcal Infections; Swine Diseases
PubMed: 37498866
DOI: 10.1371/journal.pone.0288840 -
Methods in Molecular Biology (Clifton,... 2024Establishing a biofilm infection model in vivo allows a better understanding of the underlying infection mechanisms of bacteria. Here we describe a method for...
Establishing a biofilm infection model in vivo allows a better understanding of the underlying infection mechanisms of bacteria. Here we describe a method for constructing an in vivo biofilm model of Streptococcus suis. The animal modeled is a piglet, which is the natural reservoir of S. suis, and the mode of clinical infection is simulated by intranasal inoculation of S. suis. This model is in line with clinical practice, easy to operate, and has good repeated stability.
Topics: Biofilms; Animals; Streptococcus suis; Swine; Streptococcal Infections; Disease Models, Animal
PubMed: 38884908
DOI: 10.1007/978-1-0716-3898-9_3 -
Microorganisms Sep 2023Antimicrobial resistance is an important health issue in human and veterinary medicine. The aim of this study was to monitor the antimicrobial resistance of three of the...
Antimicrobial resistance is an important health issue in human and veterinary medicine. The aim of this study was to monitor the antimicrobial resistance of three of the most important bacteria involved in porcine respiratory disease. A total of 465 isolates were tested during the 2017-2022 period for antimicrobial susceptibility for (n = 137), (n = 207), and (n = 121) by disk diffusion method. The results were interpreted by CLSI breakpoints, where available. High rates of susceptibility (from 90 to >99%) were observed for cefquinome, ceftiofur, amoxicillin + clavulanic acid, amoxicillin, penicillin, ampicillin, florfenicol, enrofloxacin, marbofloxacin, and trimethoprim-sulfamethoxazole. isolates showed high resistance to streptomycin (77%), gentamycin (45%), tilmicosin (39%) erythromycin (33%), oxytetracycline (19%), and tetracycline (18%). For , the highest rates of resistance were observed for streptomycin (98%), tetracycline (75%), oxytetracycline (72%), doxycycline (52%), and erythromycin (51%). presented a high rate of resistance for streptomycin (63%), tilmicosin (29%), oxytetracycline (13%), and tetracycline (14%). Bacteria isolates maintained high susceptibility against antimicrobial agents usually used against the mainly respiratory tract pathogens of swine. Resistance for streptomycin, tetracycline, oxytetracycline, and tilmicosin was high for all the tested pathogens.
PubMed: 37894069
DOI: 10.3390/microorganisms11102410