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Microbial Genomics Apr 2022is a causative agent of pleuropneumonia in pigs of all ages. . is divided into 19 serovars based on capsular polysaccharides (CPSs) and lipopolysaccharides. The...
is a causative agent of pleuropneumonia in pigs of all ages. . is divided into 19 serovars based on capsular polysaccharides (CPSs) and lipopolysaccharides. The serovars of isolates are commonly determined by serological tests and multiplex PCR. This study aimed to develop a genomic approach for typing by screening for the presence of the species-specific gene in whole-genome sequencing (WGS) reads and identifying capsule locus (KL) types in genome assemblies. A database of the . KL, including CPS synthesis and CPS export genes, was established and optimized for Kaptive. To test the developed genomic approach, WGS reads of 189 . isolates and those of 66 samples from 14 other bacterial species were analysed. ariba analysis showed that was detected in all 189 . samples. These -positive WGS reads were assembled into genome assemblies and assessed. A total of 105 . genome assemblies that passed the quality assessment were analysed by Kaptive analysis against the . KL database. The results showed that 97 assemblies were classified and predicted as 13 serovars, which matched the serovar information obtained from the literature. The six genome assemblies from previously nontypable isolates were typed and predicted as serovars 17 and 18. Notably, one of the two “” samples was positive, and its genome assembly was typed as KL03 with high identity and predicted as . serovar 3. Collectively, a genomic approach was established and could accurately determine the KL type of . isolates using WGS reads. This approach can be used with high-quality genome assemblies for predicting . serovars and for retrospective analysis.
Topics: Actinobacillus pleuropneumoniae; Animals; Serogroup; Serotyping; Swine; Swine Diseases
PubMed: 35404221
DOI: 10.1099/mgen.0.000780 -
Canadian Journal of Veterinary Research... Apr 2004Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia. Infection by A. pleuropneumoniae is a multifactorial process governed by many... (Review)
Review
Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia. Infection by A. pleuropneumoniae is a multifactorial process governed by many virulence factors acting alone or, more often, in concert to establish the pathogen in the porcine host. The aim of this short review is to present recent data concerning important surface molecules of A. pleuropneumoniae; namely, lipopolysaccharides, capsular polysaccharides, and a subset of outer membrane proteins involved in iron uptake.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Capsules; Iron; Polysaccharides, Bacterial; Swine; Swine Diseases; Virulence
PubMed: 15188950
DOI: No ID Found -
International Journal of Molecular... Jul 2023(APP) is the causative pathogen of porcine pleuropneumonia, a highly contagious respiratory disease in the pig industry. The increasingly severe antimicrobial...
(APP) is the causative pathogen of porcine pleuropneumonia, a highly contagious respiratory disease in the pig industry. The increasingly severe antimicrobial resistance in APP urgently requires novel antibacterial alternatives for the treatment of APP infection. In this study, we investigated the effect of tea polyphenols (TP) against APP. MIC and MBC of TP showed significant inhibitory effects on bacteria growth and caused cellular damage to APP. Furthermore, TP decreased adherent activity of APP to the newborn pig tracheal epithelial cells (NPTr) and the destruction of the tight adherence junction proteins β-catenin and occludin. Moreover, TP improved the survival rate of APP infected mice but also attenuated the release of the inflammation-related cytokines IL-6, IL-8, and TNF-α. TP inhibited activation of the TLR/MAPK/PKC-MLCK signaling for down-regulated TLR-2, TLR4, p-JNK, p-p38, p-PKC-α, and MLCK in cells triggered by APP. Collectively, our data suggest that TP represents a promising therapeutic agent in the treatment of APP infection.
Topics: Animals; Swine; Mice; Pleuropneumonia; Actinobacillus pleuropneumoniae; Toll-Like Receptor 4; Actinobacillus; Tight Junctions; Lung; Actinobacillus Infections; Mycoplasma Infections; Tea; Swine Diseases
PubMed: 37511601
DOI: 10.3390/ijms241411842 -
The Journal of Veterinary Medical... Sep 2019Actinobacillus species are known to be pathogenic to horses. To clarify etiological agents of actinobacillosis in Japanese adult horses, 27 isolates from Japanese...
Actinobacillus species are known to be pathogenic to horses. To clarify etiological agents of actinobacillosis in Japanese adult horses, 27 isolates from Japanese Thoroughbred racehorses putatively identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry as Actinobacillus were further identified by PCR of the A. equuli toxin gene, by CAMP test, and by 16S rRNA sequencing analysis. Actinobacillus equuli subsp. haemolyticus was isolated most frequently (16/27) and was related to respiratory infections. Actinobacillus equuli subsp. equuli (4/27) was isolated from chronic cases or concomitant with other bacterial infections. The remainder were A. pleuropneumoniae, unclassified Actinobacillus species and Pasteurella caballi. Actinobacillus equuli including subsp. haemolyticus and subsp. equuli were the species most frequently isolated from equine actinobacillosis in Japan.
Topics: Actinobacillus; Actinobacillus Infections; Animals; Bacterial Proteins; DNA, Bacterial; Horse Diseases; Horses; Japan; Pasteurella; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 31292334
DOI: 10.1292/jvms.19-0192 -
Journal of Veterinary Internal Medicine Mar 2020There are limited data on potential dysbiosis of the airway microbiota in horses with asthma.
BACKGROUND
There are limited data on potential dysbiosis of the airway microbiota in horses with asthma.
HYPOTHESIS/OBJECTIVES
We hypothesized that the respiratory microbiota of horses with moderate asthma is altered. Our objectives were (a) to quantify tracheal bacterial populations using culture and qPCR, (2) to compare aerobic culture and qPCR, and (c) to correlate bacterial populations with bronchoalveolar lavage fluid (BALF) cytology.
ANIMALS
Eighteen horses with moderate asthma from a hospital population and 10 controls.
METHODS
Prospective case-control study. Aerobic culture was performed on tracheal aspirates, and streptococci, Pasteurella multocida, Chlamydophila spp., Mycoplasma spp., as well as 16S (bacterial) and 18S (fungal) rRNA subunits were quantified by qPCR.
RESULTS
Potential pathogens such as Streptococcus spp., Actinobacillus spp., and Pasteurellaceae were isolated from 8, 5, and 6 horses with asthma and 3, 0, and 2 controls, respectively. There was a positive correlation between Streptococcus spp. DNA and 16S rRNA gene (r ≥ 0.7, P ≤ 0.02 in both groups), but the overall bacterial load (16S) was lower in asthma (1.5 ± 1.3 versus 2.5 ± 0.8 × 10 copy/μL, P < 0.05). There was no association between microbial populations and clinical signs, tracheal mucus or BALF inflammation.
CONCLUSIONS AND CLINICAL IMPORTANCE
This study does not support that bacterial overgrowth is a common feature of chronic moderate asthma in horses. Lower bacterial load could suggest dysbiosis of the lower airways, either as a consequence of chronic inflammation or previous treatments, or as a perpetuating factor of inflammation.
Topics: Actinobacillus; Animals; Asthma; Bronchoalveolar Lavage Fluid; Case-Control Studies; Female; Horse Diseases; Horses; Male; Pasteurellaceae; Prospective Studies; Streptococcus; Trachea
PubMed: 31985115
DOI: 10.1111/jvim.15707 -
The Journal of Veterinary Medical... May 2022The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely...
The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely isolated from ruminants. We describe here the isolation of A. suis sensu stricto from a newborn calf that died on a dairy farm in Japan. Identification of the isolate was performed by phenotypic and genotypic characterization, with the latter consisting of nucleotide sequence analyses of the 16S rRNA gene plus three housekeeping genes, rpoB, infB and recN.
Topics: Actinobacillus; Actinobacillus Infections; Actinobacillus suis; Animals; Phylogeny; RNA, Ribosomal, 16S; Swine; Swine Diseases
PubMed: 35387957
DOI: 10.1292/jvms.22-0044 -
Microbial Pathogenesis Nov 2022Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae affects pig health status and the swine industry worldwide. Despite the extensive number of studies...
Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae affects pig health status and the swine industry worldwide. Despite the extensive number of studies focused on A. pleuropneumoniae infection and vaccine development, a thorough analysis of the A. pleuropneumoniae exoproteome is still missing. Using a complementary approach of quantitative proteomics and immunoproteomics we gained an in-depth insight into the A. pleuropneumoniae serotype 2 exoproteome, which provides the basis for future functional studies. Label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed 593 exoproteins, of which 104 were predicted to be virulence factors. The RTX toxins ApxIIA and ApxIIIA -were found to be the most abundant proteins in the A. pleuropneumoniae serotype 2 exoproteome. Furthermore, the ApxIVA toxin was one of the proteins showing the highest abundance, although ApxIVA is commonly assumed to be expressed exclusively in vivo. Our study revealed several antigens, including proteins with moonlight functions, such as the elongation factor (EF)-Tu, and proteins linked to specific metabolic traits, such as the maltodextrin-binding protein MalE, that warrant future functional characterization and might present potential targets for novel therapeutics and vaccines. Our Ig-classes specific serological proteome analysis (SERPA) approach allowed us to explore the development of the host humoral immune response over the course of the infection. These SERPAs pinpointed proteins that might play a key role in virulence and persistence and showed that the immune response to the different Apx toxins is distinct. For instance, our results indicate that the ApxIIIA toxin has properties of a thymus-independent antigen, which should be studied in more detail.
Topics: Swine; Animals; Actinobacillus pleuropneumoniae; Pleuropneumonia; Actinobacillus Infections; Proteomics; Proteome; Antigens, T-Independent; Chromatography, Liquid; Swine Diseases; Bacterial Proteins; Tandem Mass Spectrometry; Mycoplasma; Virulence Factors; Peptide Elongation Factors
PubMed: 36087692
DOI: 10.1016/j.micpath.2022.105759 -
Veterinary Microbiology Apr 2018The aim of this study was to investigate isolates of Actinobacillus pleuropneumoniae previously designated serologically either as non-typable (NT) or as 'K2:07', which...
The aim of this study was to investigate isolates of Actinobacillus pleuropneumoniae previously designated serologically either as non-typable (NT) or as 'K2:07', which did not produce serovar-specific amplicons in PCR assays. We used whole genome sequencing to identify the capsule (CPS) loci of six previously designated biovar 1 NT and two biovar 1 'K2:O7' isolates of A. pleuropneumoniae from Denmark, as well as a recent biovar 2 NT isolate from Canada. All of the NT isolates have the same six-gene type I CPS locus, sharing common cpsABC genes with serovars 2, 3, 6, 7, 8, 9, 11 and 13. The two 'K2:O7' isolates contain a unique three-gene type II CPS locus, having a cpsA gene similar to that of serovars 1, 4, 12, 14 and 15. The previously NT isolates share the same O-antigen genes, found between erpA and rpsU, as serovars 3, 6, 8, and 15. Whereas the 'K2:O7' isolates, have the same O-antigen genes as serovar 7, which likely contributed to their previous mis-identification. All of the NT and 'K2:O7' isolates have only the genes required for production of ApxII (apxIICA structural genes, and apxIBD export genes). Rabbit polyclonal antisera raised against representative isolates with these new CPS loci demonstrated distinct reactivity compared to the 16 known serovars. The serological and genomic results indicate that the isolates constitute new serovars 17 (previously NT) and 18 (previously 'K2:O7'). Primers designed for amplification of specific serovar 17 and 18 sequences for molecular diagnostics will facilitate epidemiological tracking of these two new serovars of A. pleuropneumoniae.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Capsules; Canada; DNA Primers; DNA, Bacterial; Denmark; Genotype; Polymerase Chain Reaction; Serogroup; Serotyping; Swine; Swine Diseases; Whole Genome Sequencing
PubMed: 29615241
DOI: 10.1016/j.vetmic.2018.02.019 -
Microbiology and Immunology Jul 2016Apx toxins produced by Actinobacillus pleuropneumoniae are essential components of new generation vaccines. In this study, apxIIA and apxIIIA genes of serovars 2, 3, 4,...
Apx toxins produced by Actinobacillus pleuropneumoniae are essential components of new generation vaccines. In this study, apxIIA and apxIIIA genes of serovars 2, 3, 4, 6, 8 and 15 were cloned and sequenced. Amino acid sequences of ApxIIA proteins of serovars 2, 3, 4, 6, 8 and 15 were almost identical to those of serovars 1, 5, 7, 9 and 11-13. Immunoblot analysis showed that rApxIIA from serovars 2 and 15 reacts strongly with sera from animals infected with various serovars. Sequence analysis revealed that ApxIIIA proteins has two variants, one in strains of serovar 2 and the other in strains of serovars 3, 4, 6, 8 and 15. A mouse cross-protection study showed that mice actively immunized with rApxIIIA/2 or rApxIIIA/15 are protected against challenge with A. pleuropneumoniae strains of serovars 3, 4, 6, 8, 15, and 2 expressing ApxIII/15 and ApxIII/2, respectively. Similarly, mice passively immunized with rabbit anti-rApxIIIA/2 or anti-rApxIIIA/15 sera were found to be protected against challenge with strains of serovars 2 and 15. Our study revealed antigenic and sequence similarities within ApxIIA and ApxIIIA proteins, which may help in the development of effective vaccines against disease caused by A. pleuropneumoniae.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Amino Acid Sequence; Animals; Antibodies, Bacterial; Bacterial Proteins; Gene Expression; Hemolysin Proteins; Immunization; Mice; Models, Molecular; Protein Conformation; Protein Domains; Rabbits; Recombinant Fusion Proteins; Serogroup; Swine
PubMed: 27211905
DOI: 10.1111/1348-0421.12388 -
Acta Veterinaria Scandinavica 2002The objective of the study was to identify risk factors for reintroduction of Actinobacillus pleuopneumoniae and Mycoplasma hyopneumoniae (enzootic pneumonia) onto pig...
Incidence of reinfections with Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae in pig farms located in respiratory-disease-free regions of Switzerland--identification and quantification of risk factors.
The objective of the study was to identify risk factors for reintroduction of Actinobacillus pleuopneumoniae and Mycoplasma hyopneumoniae (enzootic pneumonia) onto pig farms in areas in Switzerland that were involved in an eradication programme from 1996 to 1999 and to assess the role of dealers in relation to these reinfections. The study was based on the comparison of pig farms that were reinfected in the year 2000 (cases) and pig farms that remained uninfected in the same area (controls). Additionally, data were collected from Swiss pig dealers and transport companies. Out of a total of 3983 farms, 107 farms were reinfected in the year 2000. The incidences were 0.1% for Actinobacillus pleuopneumoniae and 2.6% for Mycoplasma hyopneumoniae (enzootic pneumonia). Compared to reinfection rates prior to the eradication programme, this is a considerable reduction. Statistically significant risk factors for the reinfection were 'finishing farm', 'large mixed breeding-finishing farm', 'reinfected neighbour' and 'parking site for pig transport vehicles close to the farm'. Pig farmers that purchased pigs from only one supplier per batch had a lower risk of reintroducing infection (protective factor). As long as infected and uninfected regions co-exist in Switzerland, direct and indirect contact between farms, pig herds and slaughter sites via transport vehicles are a major pathway of disease spread. Risk management measures linked to these contacts are therefore of key importance. The survey of dealers indicated various areas for improvement such as strategic planning of pick-up routes or cleaning and disinfecting of trucks.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Incidence; Mycoplasma Infections; Recurrence; Risk Factors; Surveys and Questionnaires; Swine; Swine Diseases; Switzerland
PubMed: 12564544
DOI: 10.1186/1751-0147-43-145