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Journal of Veterinary Internal Medicine May 2021Nicoletella semolina was identified in the airways of horses and its low prevalence could be because of its difficult differentiation from other Pasteurellaceae.
BACKGROUND
Nicoletella semolina was identified in the airways of horses and its low prevalence could be because of its difficult differentiation from other Pasteurellaceae.
OBJECTIVES
To develop a molecular method for the identification of N. semolina and to evaluate its prevalence in the mouth and the airways of healthy and severe asthmatic horses.
ANIMALS
Six healthy and 6 severely asthmatic horses in phase I, 10 severely asthmatic horses in phase II, and 10 healthy horses in phase III.
METHODS
Cohort (phases I and II) and cross-sectional (phase III) studies. Quantitative polymerase chain reaction primers targeting the sodA gene were optimized. N. semolina was quantified in oral and nasal washes and in bronchoalveolar lavage fluid (BALF; phase I, sampled twice), in nasal washes and BALF (phase II, sampled twice), and in nasal washes (phase III).
RESULTS
N. semolina was found in the nose of 5, 10, and 9 horses in phases I, II, and III, respectively (first sampling for phases I and II). Six BALF from 5 different horses were positive for N. semolina in phase II. In phase I, there was no significant difference in the nasal loads of healthy horses (median (range): 2.04 × 10 copies/mL (0-2.44 × 10 )) and asthmatic horses in exacerbation (3.75 × 10 (0-4.84 × 10 ); Wilcoxon's rank sum test, P = .57).
CONCLUSIONS AND CLINICAL IMPORTANCE
N. semolina is commonly found in the airways of horses. The potential pathogenicity of N. semolina remains to be elucidated, but the molecular technique we developed will facilitate future studies.
Topics: Animals; Asthma; Bronchoalveolar Lavage Fluid; Cross-Sectional Studies; Horse Diseases; Horses; Pasteurellaceae
PubMed: 33942932
DOI: 10.1111/jvim.16140 -
Molecular Oral Microbiology Jun 2016Aggregatibacter actinomycetemcomitans is a perio-pathogenic bacteria that has long been associated with localized aggressive periodontitis. The mechanisms of its... (Review)
Review
Aggregatibacter actinomycetemcomitans is a perio-pathogenic bacteria that has long been associated with localized aggressive periodontitis. The mechanisms of its pathogenicity have been studied in humans and preclinical experimental models. Although different serotypes of A. actinomycetemcomitans have differential virulence factor expression, A. actinomycetemcomitans cytolethal distending toxin (CDT), leukotoxin, and lipopolysaccharide (LPS) have been most extensively studied in the context of modulating the host immune response. Following colonization and attachment in the oral cavity, A. actinomycetemcomitans employs CDT, leukotoxin, and LPS to evade host innate defense mechanisms and drive a pathophysiologic inflammatory response. This supra-physiologic immune response state perturbs normal periodontal tissue remodeling/turnover and ultimately has catabolic effects on periodontal tissue homeostasis. In this review, we have divided the host response into two systems: non-hematopoietic and hematopoietic. Non-hematopoietic barriers include epithelium and fibroblasts that initiate the innate immune host response. The hematopoietic system contains lymphoid and myeloid-derived cell lineages that are responsible for expanding the immune response and driving the pathophysiologic inflammatory state in the local periodontal microenvironment. Effector systems and signaling transduction pathways activated and utilized in response to A. actinomycetemcomitans will be discussed to further delineate immune cell mechanisms during A. actinomycetemcomitans infection. Finally, we will discuss the osteo-immunomodulatory effects induced by A. actinomycetemcomitans and dissect the catabolic disruption of balanced osteoclast-osteoblast-mediated bone remodeling, which subsequently leads to net alveolar bone loss.
Topics: Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Alveolar Bone Loss; Homeostasis; Host-Pathogen Interactions; Humans; Immunity, Innate; Inflammasomes; Pasteurellaceae Infections; Signal Transduction; Virulence Factors
PubMed: 26197893
DOI: 10.1111/omi.12119 -
A simple and novel method for retrieval of Pasteurellaceae from swab samples collected in the field.MicrobiologyOpen Oct 2013Traditionally it has been difficult or impossible to collect and preserve bacterial samples of especially fastidious bacteria in mixed primary cultures, unless the...
Traditionally it has been difficult or impossible to collect and preserve bacterial samples of especially fastidious bacteria in mixed primary cultures, unless the samples could be transported to a laboratory within approximately 24 h. Therefore, a simple novel method for preserving swab samples until bacterial isolation can be completed in the laboratory was developed and evaluated. Pasteurellaceae bacteria were used as a representative for fastidious bacteria. A 7.5% glucose serum medium was used as freeze medium. Swab samples were soaked in the medium a maximum of 2 h after collection and stored at -20°C. As a control study, 15 samples were collected from the oral cavity of a captive brown bear. One was immediately plated, while the remaining 12 swabs were stored at -20°C for 7 days and multiples of 30 days up to 330 days prior to plating. Two samples were stored without the medium for 7 and 30 days prior to plating. From a field setting in Greenland, eight polar bear samples were collected and subsequently stored for 240 to 259 days at -20°C before incubation. Pasteurellaceae bacteria were isolated and genotyped from all samples stored in the freeze medium, indicating that the medium enabled the bacteria to survive for at least 330 days at -20°C. The 100% recovery of target organisms in the polar bear samples even following lengthy storage and transport demonstrates that the method is very useful under remote field conditions.
Topics: Animals; Bacterial Typing Techniques; Cryopreservation; Culture Media; Greenland; Mouth; Pasteurellaceae; Specimen Handling; Ursidae
PubMed: 23897719
DOI: 10.1002/mbo3.114 -
Biochemical and Biophysical Research... Mar 2022L-enantiomers of antimicrobial peptides (AMPs) are sensitive to proteolytic degradation; however, D-enantiomers of AMPs are expected to provide improved proteolytic... (Comparative Study)
Comparative Study
L-enantiomers of antimicrobial peptides (AMPs) are sensitive to proteolytic degradation; however, D-enantiomers of AMPs are expected to provide improved proteolytic resistance. The present study aimed to comparatively investigate the in vitro antibacterial activity, trypsin and serum stability, toxicity, and in vivo antibacterial activity of L-enantiomeric bovine NK2A (L-NK2A) and its D-enantiomeric NK2A (D-NK2A). Circular dichroism spectroscopy of D-NK2A and L-NK2A in anionic liposomes showed α-helical structures and the α-helical conformation of D-NK2A was a mirror image of L-NK2A. Both D-NK2A and L-NK2A displayed minimal in vitro and in vivo toxicities. RP-HPLC and mass spectrometry analyses revealed that D-NK2A, but not L-NK2A, was resistant to trypsin digestion. D-NK2A and L-NK2A showed similar in vitro bacterial killing activities against Histophilus somni. Slightly reduced antibacterial activity was observed when D-NK2A and L-NK2A were pre-incubated with serum. Confocal and transmission electron microscopic findings confirmed that both peptides induced disruption of bacterial inner- and outer-membranes. Improved survivals with D-NK2A treatment were observed when compared to L-NK2A in a murine model of acute H. somni septicemia. We conclude that antibacterial activity and mode of action of NK2A are not chiral specific. With further optimization, D-NK2A may be a viable AMP candidate to combat bacterial infections.
Topics: Animals; Anti-Bacterial Agents; Antimicrobial Peptides; Cattle; Circular Dichroism; Kaplan-Meier Estimate; Mice; Microscopy, Electron, Transmission; Pasteurellaceae; Pasteurellaceae Infections; Protein Stability; Protein Structure, Secondary; Proteolipids; Stereoisomerism
PubMed: 35101666
DOI: 10.1016/j.bbrc.2022.01.071 -
Journal of Bacteriology Oct 2006
Review
Topics: Animals; Bacterial Proteins; Humans; NAD; Niacinamide; Pasteurellaceae; Pyridinium Compounds; Repressor Proteins
PubMed: 16980474
DOI: 10.1128/JB.00432-06 -
Journal of Global Antimicrobial... Dec 2023The aim of this study was to characterize the floR-carrying plasmids originating from Glaesserella parasuis and Actinobacillus indolicus isolated from pigs with...
OBJECTIVES
The aim of this study was to characterize the floR-carrying plasmids originating from Glaesserella parasuis and Actinobacillus indolicus isolated from pigs with respiratory disease in China.
METHODS
A total of 125 G. parasuis and 28 A. indolicus strains collected between 2009 and 2022 were screened for florfenicol resistance. Characterization of floR-positive isolates and plasmids were determined by antimicrobial susceptibility testing, serotyping, multilocus sequence typing (MLST), conjugation and transformation assays, whole-genome sequencing (WGS), and phylogenetic analysis.
RESULTS
One A. indolicus and six G. parasuis were identified as positive for floR. The six G. parasuis were assigned to four different serovars, including serovars 6, 7, 9, and unknown. In addition to strain XP11, six floR genes were located on plasmids. The six floR-bearing plasmids could be transformed into Pasteurella multocida and divided into two different types, including ∼5000 bp and ∼6000 bp plasmids. The ∼5000 bp plasmids consisting of rep, lysR, mobB, and floR genes, exhibited high similarity among Pasteurellaceae bacteria. Furthermore, the ∼6000 bp plasmids, consisting of rep, lysR, mobC, mobA/L, and floR genes, showed high similarity between G. parasuis and Actinobacillus Spp. Notably, WGS results showed that the floR modules of the two types of plasmids could be transferred and integrated into the diverse Pasteurellaceae- origined plasmids.
CONCLUSION
This study firstly reported the characterization of floR-carrying plasmids from A. indolicus and a non-virulent serovar of G. parasuis in pigs in China and elucidated the transmission mechanism of the floR resistance gene among the Pasteurellaceae family.
Topics: Animals; Swine; Anti-Bacterial Agents; Multilocus Sequence Typing; Phylogeny; Plasmids; Actinobacillus
PubMed: 37726088
DOI: 10.1016/j.jgar.2023.09.009 -
PloS One 2017Respiratory disease has been a persistent problem for the recovery of bighorn sheep (Ovis canadensis), but has uncertain etiology. The disease has been attributed to...
Respiratory disease has been a persistent problem for the recovery of bighorn sheep (Ovis canadensis), but has uncertain etiology. The disease has been attributed to several bacterial pathogens including Mycoplasma ovipneumoniae and Pasteurellaceae pathogens belonging to the Mannheimia, Bibersteinia, and Pasteurella genera. We estimated detection probability for these pathogens using protocols with diagnostic tests offered by a fee-for-service laboratory and not offered by a fee-for-service laboratory. We conducted 2861 diagnostic tests on swab samples collected from 476 bighorn sheep captured across Montana and Wyoming to gain inferences regarding detection probability, pathogen prevalence, and the power of different sampling methodologies to detect pathogens in bighorn sheep populations. Estimated detection probability using fee-for-service protocols was less than 0.50 for all Pasteurellaceae and 0.73 for Mycoplasma ovipneumoniae. Non-fee-for-service Pasteurellaceae protocols had higher detection probabilities, but no single protocol increased detection probability of all Pasteurellaceae pathogens to greater than 0.50. At least one protocol resulted in an estimated detection probability of 0.80 for each pathogen except Mannheimia haemolytica, for which the highest detection probability was 0.45. In general, the power to detect Pasteurellaceae pathogens at low prevalence in populations was low unless many animals were sampled or replicate samples were collected per animal. Imperfect detection also resulted in low precision when estimating prevalence for any pathogen. Low and variable detection probabilities for respiratory pathogens using live-sampling protocols may lead to inaccurate conclusions regarding pathogen community dynamics and causes of bighorn sheep respiratory disease epizootics. We recommend that agencies collect multiples samples per animal for Pasteurellaceae detection, and one sample for Mycoplasma ovipneumoniae detection from at least 30 individuals to reliably detect both Pasteurellaceae and Mycoplasma ovipneumoniae at the population-level. Availability of PCR diagnostic tests to wildlife management agencies would improve the ability to reliably detect Pasteurellaceae in bighorn sheep populations.
Topics: Animals; DNA, Bacterial; Mycoplasma ovipneumoniae; Pasteurellaceae; Population Density; Prevalence; Real-Time Polymerase Chain Reaction; Respiratory Tract Infections; Sheep; Sheep Diseases; Sheep, Bighorn; Specimen Handling
PubMed: 28708832
DOI: 10.1371/journal.pone.0180689 -
New plasmid tools for genetic analysis of Actinobacillus pleuropneumoniae and other pasteurellaceae.Applied and Environmental Microbiology Oct 2009We have generated a set of plasmids, based on the mobilizable shuttle vector pMIDG100, which can be used as tools for genetic manipulation of Actinobacillus...
We have generated a set of plasmids, based on the mobilizable shuttle vector pMIDG100, which can be used as tools for genetic manipulation of Actinobacillus pleuropneumoniae and other members of the Pasteurellaceae. A tandem reporter plasmid, pMC-Tandem, carrying promoterless xylE and gfpmut3 genes downstream of a multiple-cloning site (MCS), can be used for identification of transcriptional regulators and conditions which favor gene expression from different cloned promoters. The ability to detect transcriptional regulators using the tandem reporter system was validated in A. pleuropneumoniae using the cloned rpoE (sigma(E)) promoter (P). The resulting plasmid, pMCrpoEP, was used to identify a mutant defective in production of RseA, the negative regulator of sigma(E), among a bank of random transposon mutants, as well as to detect induction of sigma(E) following exposure of A. pleuropneumoniae to ethanol or heat shock. pMCsodCP, carrying the cloned sodC promoter of A. pleuropneumoniae, was functional in A. pleuropneumoniae, Haemophilus influenzae, Haemophilus parasuis, Mannheimia haemolytica, and Pasteurella multocida. Two general expression vectors, pMK-Express and pMC-Express, which differ in their antibiotic resistance markers (kanamycin and chloramphenicol, respectively), were constructed for the Pasteurellaceae. Both plasmids have the A. pleuropneumoniae sodC promoter upstream of the gfpmut3 gene and an extended MCS. Replacement of gfpmut3 with a gene of interest allows complementation and heterologous gene expression, as evidenced by expression of the Haemophilus ducreyi nadV gene in A. pleuropneumoniae, rendering the latter NAD independent.
Topics: Base Sequence; Cloning, Molecular; DNA, Bacterial; Genes, Bacterial; Genes, Reporter; Genetic Vectors; Molecular Biology; Molecular Sequence Data; Pasteurellaceae; Plasmids; Promoter Regions, Genetic; Sequence Analysis, DNA; Transcription, Genetic
PubMed: 19666733
DOI: 10.1128/AEM.00809-09 -
Journal of the American Association For... May 2023Rodents used in biomedical research are maintained as specific pathogen-free (SPF) by employing biosecurity measures that eliminate and exclude adventitious infectious...
Rodents used in biomedical research are maintained as specific pathogen-free (SPF) by employing biosecurity measures that eliminate and exclude adventitious infectious agents known to confound research. The efficacy of these practices is assessed by routine laboratory testing referred to as health monitoring (HM). This study summarizes the results of HM performed at Charles River Research Animal Diagnostic Services (CR-RADS) on samples submitted by external (non-Charles River) clients between 2003 and 2020. Summarizing this vast amount of data has been made practicable by the recent introduction of end-user business intelligence tools to Excel. HM summaries include the number of samples tested and the percent positive by diagnostic methodology, including direct examination for parasites, cultural isolation and identification for bacteria, serology for antibodies to viruses and fastidious microorganisms, and polymerase chain reaction (PCR) assays for pathogen-specific genomic sequences. Consistent with comparable studies, the percentages of pathogen-positive samples by diagnostic methodology and year interval are referred to as period prevalence estimates (%P). These %P substantiate the elimination of once common respiratory pathogens, such as Sendai virus, and reductions in the prevalence of other agents considered common, such as the rodent coronaviruses and parvoviruses. Conversely, the %P of certain pathogens, for example, murine norovirus (MNV), , , and parasites remain high, perhaps due to the increasing exchange of genetically engineered mutant (GEM) rodents among researchers and the challenges and high cost of eliminating these agents from rodent housing facilities. Study results also document the growing role of PCR in HM because of its applicability to all pathogen types and its high specificity and sensitivity; moreover, PCR can detect pathogens in samples collected antemortem directly from colony animals and from the environment, thereby improving the detection of host-adapted, environmentally unstable pathogens that are not efficiently transmitted to sentinels by soiled bedding.
Topics: Rats; Animals; Mice; Prevalence; Polymerase Chain Reaction; Bacteria; Helicobacter; Pasteurellaceae; Housing, Animal
PubMed: 37127407
DOI: 10.30802/AALAS-JAALAS-22-000097 -
Journal of Applied Microbiology Apr 2010The aim of the present investigation was to identify and characterize Pasteurella-like isolates obtained from clinically affected psittacine birds.
AIMS
The aim of the present investigation was to identify and characterize Pasteurella-like isolates obtained from clinically affected psittacine birds.
METHODS AND RESULTS
A total of 37 isolates from psittacine birds tentatively classified with the family Pasteurellaceae were characterized phenotypically. The genetic relationship was investigated by sequencing of partial rpoB and 16S rRNA genes for selected isolates. The results obtained were compared with the data from 16 reference strains. Nine isolates were identified as Gallibacterium spp., 16 as Volucribacter spp. or Volucribacter-like, while 11 isolates were classified as taxon 44 of Bisgaard. A single isolate was identified as Pasteurella multocida.
CONCLUSIONS
Characterization of Pasteurellaceae by traditional methods is often inconclusive because of inconsistent reactions and phenotypic diversity. For the same reason, genotyping is essential to allow proper classification as demonstrated in the present study.
SIGNIFICANCE AND IMPACT OF THE STUDY
Limited information exists on the isolation and significance of Pasteurellaceae associated with clinically affected psittacine birds showing signs of digestive and/or respiratory disorders. The present investigations demonstrated that these organisms are widely distributed among clinically affected birds, but isolation of these taxa cannot be unambiguously correlated with the symptoms observed.
Topics: Animals; Bacterial Proteins; Bird Diseases; Molecular Sequence Data; Pasteurella Infections; Pasteurellaceae; Phenotype; Phylogeny; Psittaciformes; RNA, Ribosomal, 16S
PubMed: 19732214
DOI: 10.1111/j.1365-2672.2009.04518.x