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PloS One 2012The extracellular proteome (secretome) of periodontitis-associated bacteria may constitute a major link between periodontitis and systemic diseases. To obtain an...
The extracellular proteome (secretome) of periodontitis-associated bacteria may constitute a major link between periodontitis and systemic diseases. To obtain an overview of the virulence potential of Aggregatibacter actinomycetemcomitans, an oral and systemic human pathogen implicated in aggressive periodontitis, we used a combined LC-MS/MS and bioinformatics approach to characterize the secretome and protein secretion pathways of the rough-colony serotype a strain D7S. LC-MS/MS revealed 179 proteins secreted during biofilm growth. Further to confirming the release of established virulence factors (e.g. cytolethal distending toxin [CDT], and leukotoxin [LtxA]), we identified additional putative virulence determinants in the secretome. These included DegQ, fHbp, LppC, Macrophage infectivity protein (MIP), NlpB, Pcp, PotD, TolB, and TolC. This finding indicates that the number of extracellular virulence-related proteins is much larger than previously demonstrated, which was also supported by in silico analysis of the strain D7S genome. Moreover, our LC-MS/MS and in silico data revealed that at least Type I, II, and V secretion are actively used to excrete proteins directly into the extracellular space, or via two-step pathways involving the Sec/Tat systems for transport across the inner membrane, and outer membrane factors, secretins and auto-transporters, respectively for delivery across the outer membrane. Taken together, our results provide a molecular basis for further elucidating the role of A. actinomycetemcomitans in periodontal and systemic diseases.
Topics: Bacterial Proteins; Humans; Intracellular Space; Pasteurellaceae; Protein Transport; Proteomics
PubMed: 22848560
DOI: 10.1371/journal.pone.0041662 -
Indian Journal of Medical Microbiology 2017A. actinomycetemcomitans is prevalent in periodontitis but is found in some periodontally healthy individuals as well. Certain serotypes of the organism have shown to... (Comparative Study)
Comparative Study
BACKGROUND
A. actinomycetemcomitans is prevalent in periodontitis but is found in some periodontally healthy individuals as well. Certain serotypes of the organism have shown to determine severity of the disease. The distribution of serotype and genotype is affected by geographic and ethnic variation. Therefore, the present study was aimed to detect serotypes b & c of A. actinomycetemcomitans and the genotypes and find its correlation with periodontal status.
MATERIALS AND METHODS
A total of 75 subjects (25 aggressive periodontitis, 25 chronic periodontitis and 25 periodontally healthy) in age range of 14-55 yrs were included. Subgingival plaque samples were collected and checked for the presence of A. actinomycetemcomitans. Following isolation of the organism, detection of the serotype b or c was done by multiplex PCR. Genotyping of A. actinomycetemcomitans was done by arbitrarily primed PCR(polymerase chain reaction).
RESULTS
Out of 75 plaque samples, 35(46.66%) tested positive for A. actinomycetemcomitans. Serotype c was detected in 19/35 (54.28%), whereas serotype b alone was not detected in any of the samples. Two samples were positive for both the serotypes (b and c) (5.71%) and 14 (40%) were untypeable. 14 different arbitrarily primed PCR genotypes were obtained among 35 A. actinomycetemcomitans isolates.
CONCLUSION
Serotype c was predominant in periodontally diseased as well as periodontally healthy individuals. An association could be present between genotype - serotype and genotype - periodontal status.
Topics: Adolescent; Adult; Aggregatibacter actinomycetemcomitans; Cross-Sectional Studies; Female; Genotype; Genotyping Techniques; Healthy Volunteers; Humans; Male; Middle Aged; Multiplex Polymerase Chain Reaction; Pasteurellaceae Infections; Periodontal Diseases; Serogroup; Young Adult
PubMed: 29405147
DOI: 10.4103/ijmm.IJMM_17_115 -
Infection, Genetics and Evolution :... Aug 2022Rodentibacter spp. are opportunistic pathogens that are often isolated from the upper respiratory tracts of laboratory rodents. In particular, R. pneumotropicus and R....
Rodentibacter spp. are opportunistic pathogens that are often isolated from the upper respiratory tracts of laboratory rodents. In particular, R. pneumotropicus and R. heylii require considerable caution in rodent colonies, as they cause lethal pneumonia in rodents. A new species, R. haemolyticus, has recently been classified in the genus, and a very closely related strain, Rodentibacter sp. strain JRC, has been isolated in Japan. This study focused on strain JRC by performing genomic and pathogenic analyses. Draft genome sequencing of strain JRC identified several genes coding for putative virulent proteins, including hemolysin and adhesin. Furthermore, we found a new RTX (repeats-in-structural toxin) toxin gene in the genome, which was predicted to produce a critical virulence factor (RTXIA) similar to Enterobacteriaceae. The concentrated culture supernatant containing RTX toxin (RTXIA) showed cytotoxicity toward RAW264.7 cells. Pre-incubation with anti-CD11a attenuated the cytolysis, suggesting that the concentrated culture supernatant containing RTXIA is cell surface LFA-1 mediated cytolysin. Experimental infection of strain JRC intranasally with 5 female BALB/c-Rag2 mice showed 60% lethality and was not significantly different from those of R. pneumotropicus ATCC 35149 using the log-rank test. Combined with our finding that RTXIA has an almost identical amino acid sequence (98% identity) to that of R. haemolyticus 1625/19, these results strongly suggest that RTXIA-producing strain JRC (and related R. haemolyticus) is pathogenic to immunodeficient rodents, and both agents should be excluded in laboratory rodent colonies.
Topics: Animals; Bacterial Toxins; Female; Genomics; Hemolysin Proteins; Mice; Mice, Inbred BALB C; Pasteurellaceae; Rodentia
PubMed: 35675867
DOI: 10.1016/j.meegid.2022.105314 -
Veterinary Research Feb 2021Gallibacterium anatis is a common cause of reproductive tract infection in chickens, which leads to reduced egg production and increased mortality. This study was...
Gallibacterium anatis is a common cause of reproductive tract infection in chickens, which leads to reduced egg production and increased mortality. This study was undertaken to investigate prevalence of G. anatis in 12 poultry flocks originating from Iranian provinces with leading chicken production and to determine genetic diversity, antimicrobial resistance, and the presence of major antigens of the isolates investigated. Out of the 120 chicken tracheal samples collected and tested, 84 (70%) were positive for G. anatis. Genotyping by Pulse Field Gel Electrophoresis and genome sequencing revealed a total of 24 pulsotypes for 71 strains (at a 87% similarity level) and seven genome clusters comprising 21 strains (97% similarity level), respectively. The combination of the two typing methods confirmed the presence of several genotypes originating from a common ancestor affecting poultry yet also suggested that identical clones were shared among chickens within farms and between different farms. The latter finding is to our knowledge the first example of clonal presence of G. anatis in epidemiologically unrelated farms. The 21 sequenced strains were characterized against a panel of commonly used antibiotics and showed lowered sensitivity to tetracycline (76.2%) and enrofloxacin (90.5%). The widespread presence of multiresistant G. anatis isolates calls for non-antibiotic prophylactics. Three major immunogen genes, gtxA, Gab_1309 and Gab_2312 were detected in the isolates indicating these antigens likely represent effective vaccine targets. A conserved sequence of the gtxA gene across a range of epidemiologically independent strains suggests the use of GtxA for future vaccine development purposes.
Topics: Animals; Anti-Bacterial Agents; Chickens; Drug Resistance, Multiple, Bacterial; Genome, Bacterial; Iran; Pasteurellaceae; Pasteurellaceae Infections; Phylogeny; Poultry Diseases; Whole Genome Sequencing
PubMed: 33596999
DOI: 10.1186/s13567-021-00894-1 -
MicrobiologyOpen Jun 2023Glaesserella parasuis, Mycoplasma hyorhinis, and Mycoplasma hyosynoviae are important porcine pathogens responsible for polyserositis, polyarthritis, meningitis,...
Glaesserella parasuis, Mycoplasma hyorhinis, and Mycoplasma hyosynoviae are important porcine pathogens responsible for polyserositis, polyarthritis, meningitis, pneumonia, and septicemia causing significant economic losses in the swine industry. A new multiplex quantitative polymerase chain reaction (qPCR) was designed on one hand for the detection of G. parasuis and the virulence marker vtaA to distinguish between highly virulent and non-virulent strains. On the other hand, fluorescent probes were established for the detection and identification of both M. hyorhinis and M. hyosynoviae targeting 16S ribosomal RNA genes. The development of the qPCR was based on reference strains of 15 known serovars of G. parasuis, as well as on the type strains M. hyorhinis ATCC 17981 and M. hyosynoviae NCTC 10167 . The new qPCR was further evaluated using 21 G. parasuis, 26 M. hyorhinis, and 3 M. hyosynoviae field isolates. Moreover, a pilot study including different clinical specimens of 42 diseased pigs was performed. The specificity of the assay was 100% without cross-reactivity or detection of other bacterial swine pathogens. The sensitivity of the new qPCR was demonstrated to be between 11-180 genome equivalents (GE) of DNA for M. hyosynoviae and M. hyorhinis, and 140-1200 GE for G. parasuis and vtaA. The cut-off threshold cycle was found to be at 35. The developed sensitive and specific qPCR assay has the potential to become a useful molecular tool, which could be implemented in veterinary diagnostic laboratories for the detection and identification of G. parasuis, its virulence marker vtaA, M. hyorhinis, and M. hyosynoviae.
Topics: Multiplex Polymerase Chain Reaction; Pasteurellaceae; Mycoplasma hyorhinis; Mycoplasma hyosynoviae; Swine Diseases; Animals; Swine; Mycoplasma Infections; Pasteurellaceae Infections; Pilot Projects; Sensitivity and Specificity
PubMed: 37379423
DOI: 10.1002/mbo3.1353 -
A computational strategy for the search of regulatory small RNAs in Actinobacillus pleuropneumoniae.RNA (New York, N.Y.) Sep 2016Bacterial regulatory small RNAs (sRNAs) play important roles in gene regulation and are frequently connected to the expression of virulence factors in diverse bacteria....
Bacterial regulatory small RNAs (sRNAs) play important roles in gene regulation and are frequently connected to the expression of virulence factors in diverse bacteria. Only a few sRNAs have been described for Pasteurellaceae pathogens and no in-depth analysis of sRNAs has been described for Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, responsible for considerable losses in the swine industry. To search for sRNAs in A. pleuropneumoniae, we developed a strategy for the computational analysis of the bacterial genome by using four algorithms with different approaches, followed by experimental validation. The coding strand and expression of 17 out of 23 RNA candidates were confirmed by Northern blotting, RT-PCR, and RNA sequencing. Among them, two are likely riboswitches, three are housekeeping regulatory RNAs, two are the widely studied GcvB and 6S sRNAs, and 10 are putative novel trans-acting sRNAs, never before described for any bacteria. The latter group has several potential mRNA targets, many of which are involved with virulence, stress resistance, or metabolism, and connect the sRNAs in a complex gene regulatory network. The sRNAs identified are well conserved among the Pasteurellaceae that are evolutionarily closer to A. pleuropneumoniae and/or share the same host. Our results show that the combination of newly developed computational programs can be successfully utilized for the discovery of novel sRNAs and indicate an intricate system of gene regulation through sRNAs in A. pleuropneumoniae and in other Pasteurellaceae, thus providing clues for novel aspects of virulence that will be explored in further studies.
Topics: Actinobacillus pleuropneumoniae; Algorithms; Genome, Bacterial; RNA, Small Untranslated; Sequence Analysis, RNA; Software; Transcriptome
PubMed: 27402897
DOI: 10.1261/rna.055129.115 -
BMC Veterinary Research Feb 2024Respiratory tract diseases cause significant economic loss in beef cattle. This study aimed to determine whether the application of hyperimmune serum (HS) containing...
BACKGROUND
Respiratory tract diseases cause significant economic loss in beef cattle. This study aimed to determine whether the application of hyperimmune serum (HS) containing antibodies against selected antigens of Gram-negative bacteria would improve the health and growth of different breeds of beef calves kept on three farms. Two recombinant protein antigens (Histophilus somni rHsp60 and rOMP40) were used to immunize four cows to produce HS. Eighty seven beef calves (Charolaise n = 36, Limousine n = 34, and crossbreed n = 17) were included into study. One hundred milliliters of serum were administered subcutaneously to 43 beef calves (Charolaise n = 18, Limousine n = 17, and crossbreed n = 8) twice, between 1 and 5 and 21-28 days of life. Calves were examined three times, and blood samples were taken to evaluate immunoglobulin M, G, and G2, fibrinogen, serum amyloid A, and haptoglobin concentrations and reactivity of these Ig classes of antibodies against H. somni rHsp60 and rOMP40. Average daily weight gain during the first month and until weaning was calculated.
RESULTS
HS showed higher (p ≤ 0.05) reactivity in calf sera against H. somni rHsp60 and OMP40 in IgG and IgG. In experimental calves, compared to control calves, the reactivity of IgG against rOMP40 in the second sampling was higher in Limousine calves (p ≤ 0.001) and in the other two herds (p ≤ 0.05). Serum IgG antibody activity against H. somni rHsp60 in the second sampling was higher in experimental calves than in control calves in charolaise (p ≤ 0.05) and limousine (p ≤ 0.001) herds. The reactivity of IgG against rOMP40 in the second sampling of experimental calves was higher in herds with Charolaise and Limousine calves (p ≤ 0.001) and in crossbred calves (p ≤ 0.05). In the third sampling, serum IgG antibody reactivity against rOMP40 in Limousine calves was higher (p ≤ 0.05) in the experimental group. Among the other evaluated parameters, only SAA in the second sampling in the herd with Charolaise calves and heart rate in the herd with Limousine calves were significantly higher in the control calves (p ≤ 0.05).
CONCLUSION
The application of HS to calves in all herds had an impact on specific reactivity in IgG and IgG classes against H. somni rOMP40 and rHsp60, antigens which were used for serum production.
Topics: Female; Cattle; Animals; Gram-Negative Bacteria; Recombinant Proteins; Immunoglobulin M; Pasteurellaceae; Immunoglobulin G; Cattle Diseases
PubMed: 38341558
DOI: 10.1186/s12917-024-03895-2 -
Journal of Veterinary Diagnostic... Nov 2009Several bacteria belonging to the family Pasteurellaceae are potential pathogens in rabbits. In particular, Pasteurella multocida is considered to be important, and...
Several bacteria belonging to the family Pasteurellaceae are potential pathogens in rabbits. In particular, Pasteurella multocida is considered to be important, and outbreaks caused by this species result in considerable economic losses in rabbitries. However, Pasteurellaceae spp. isolated from rabbits are poorly characterized, and thus, proper identification of P. multocida isolates from these animals is problematic and often unsatisfactory, thereby hampering epidemiological investigations. Therefore, 228 isolates from rabbit populations originating from a breeding and fattening organization with group management and postmortem cases with pasteurellosis from individual owners were phenotypically and genotypically analyzed using biochemical tests and repetitive extragenic palindromic polymerase chain reaction (REP-PCR). Furthermore, 41 samples representing observed phenotypes were selected for phylogenetic analysis using 16S ribosomal RNA and rpoB genes. The REP-PCR typing and phylogenetic analyses correlated well and appeared to be distinct molecular methods for characterization of rabbit isolates. Phenotyping, however, diverged from molecular recognition, reflecting the problematic conventional diagnosis of these strains. The fermentation of sorbitol appeared to be an imprecise indicator for P. multocida subspecies classification. According to REP-PCR and sequencing results, 82% of the isolates were characterized as P. multocida subsp. multocida, 3% as P. multocida subsp. septica, and 5% as P. multocida. Further, 5% were identified as Pasteurella canis. The other 5% represented a homogeneous group of unknown species belonging to the Pasteurellaceae. Samples obtained from individual postmortem cases demonstrated a higher phenotypic and genetic heterogeneity than samples from group management rabbits.
Topics: Animals; Bacterial Proteins; DNA Primers; Genotype; Pasteurella Infections; Pasteurella multocida; Phenotype; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Rabbits; Respiratory Tract Infections; Switzerland
PubMed: 19901279
DOI: 10.1177/104063870902100605 -
Medicina Oral, Patologia Oral Y Cirugia... Mar 2014Several studies have focused on the relationship among serotype distribution, ethnical status and geographic populations, and periodontal conditions. Studies that have... (Review)
Review
OBJECTIVE
Several studies have focused on the relationship among serotype distribution, ethnical status and geographic populations, and periodontal conditions. Studies that have investigated the prevalence and the distribution of A. actinomycetemcomitans serotypes and the relation between the different serotypes of the bacterium and periodontal status were reviewed.
MATERIAL AND METHODS
A systematic literature search for publications regarding the distribution of A. actinomycetemcomitans serotypes in subgingival samples of periodontitis patients and periodontally healthy subjects by employing polymerase chain reaction (PCR) was conducted.
RESULTS
From the 85 studies identified in the first analysis, only 12 met all inclusion and exclusion criteria. Clinical isolates from diverse geographic populations with different periodontal conditions were evaluated. Serotypes a, b and c were largely found, and serotype c was the most prevalent. They were isolated from various periodontal conditions, including aggressive periodontitis.
CONCLUSIONS
The available literature suggests that serotypes a, b, and c are globally dominant, serotypes d and e are rare, and the prevalence of the most recently identified serotype f is still unknown. It is widely accepted that distribution patterns of A. actinomycetemcomitans vary among subjects of different ethnicity and geographic regions. The correlation of different serotypes with various periodontal conditions remains unclear.
Topics: Aggregatibacter actinomycetemcomitans; Geography; Humans; Pasteurellaceae Infections; Periodontal Index; Periodontitis; Serotyping
PubMed: 24316700
DOI: 10.4317/medoral.19304 -
Journal of Veterinary Diagnostic... Sep 2018Infectious coryza, caused by Avibacterium paragallinarum, is an acute respiratory disease of poultry that can result in substantial morbidity, mortality, and economic...
Infectious coryza, caused by Avibacterium paragallinarum, is an acute respiratory disease of poultry that can result in substantial morbidity, mortality, and economic losses. In March 2017, the Turlock branch of the California Animal Health and Food Safety laboratory system encountered an unusual clinical and pathologic presentation of infectious coryza in 6 live, 29-d-old, commercial broiler chickens that were submitted for diagnostic investigation. Antemortem evaluation revealed severe neurologic signs, including disorientation, torticollis, and opisthotonos. Swollen head-like syndrome and sinusitis were also present. Histologically, severe sinusitis, cranial osteomyelitis, otitis media and interna, and meningoencephalitis were noted, explaining the clinical signs described. A. paragallinarum was readily isolated from the upper and lower respiratory tract, brain, and cranial bones. Infectious bronchitis virus (IBV) was also detected by PCR, and IBV was isolated in embryonated chicken eggs. Based on sequencing analysis, the IBV appeared 99% homologous to strain CA1737. A synergistic effect between A. paragallinarum and IBV, resulting in exacerbation of clinical signs and increased mortality, may have occurred in this case. A. paragallinarum should be considered among the possible causes of neurologic signs in chickens. Appropriate media should be used for bacterial isolation, and the role of additional contributing factors and/or complicating agents should be investigated in cases of infectious coryza.
Topics: Animals; California; Chickens; Meningoencephalitis; Otitis; Pasteurellaceae; Pasteurellaceae Infections; Polymerase Chain Reaction; Poultry Diseases
PubMed: 30129392
DOI: 10.1177/1040638718792964