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Frontiers in Immunology 2019is a low-abundance Gram-negative oral pathobiont that is highly associated with a silent but aggressive orphan disease that results in periodontitis and tooth loss in... (Review)
Review
is a low-abundance Gram-negative oral pathobiont that is highly associated with a silent but aggressive orphan disease that results in periodontitis and tooth loss in adolescents of African heritage. For the most part conducts its business by utilizing strategies allowing it to conceal itself below the radar of the host mucosal immune defense system. A great deal of misinformation has been conveyed with respect to biology in health and disease. The purpose of this review is to present misconceptions about and the strategies that it uses to colonize, survive, and evade the host. In the process manages to undermine host mucosal defenses and contribute to disease initiation. This review will present clinical observational, molecular, and interventional studies that illustrate genetic, phenotypic, and biogeographical tactics that have been recently clarified and demonstrate how survives and suppresses host mucosal defenses to take part in disease pathogenesis. At one point in time was considered to be the causative agent of Localized Aggressive Periodontitis. Currently, it is most accurate to look at as a community activist and necessary partner of a pathogenic consortium that suppresses the initial host response so as to encourage overgrowth of its partners. The data for activist role stems from molecular genetic studies complemented by experimental animal investigations that demonstrate how establishes a habitat (housing), nutritional sustenance in that habitat (food), and biogeographical mobilization and/or relocation from its initial habitat (transportation). In this manner can transfer to a protected but vulnerable domain (pocket or sulcus) where its community activism is most useful. 's "strategy" includes obtaining housing, food, and transportation at no cost to its partners challenging the economic theory that "there ain't no such thing as a free lunch." This "strategy" illustrates how co-evolution can promote survival, on one hand, and overgrowth of community members, on the other, which can result in local host dysbiosis and susceptibility to infection.
Topics: Adolescent; Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Animals; Biofilms; Genes, Bacterial; Host Microbial Interactions; Humans; Immunity, Mucosal; Models, Immunological; Pasteurellaceae Infections
PubMed: 31040843
DOI: 10.3389/fimmu.2019.00728 -
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 -
BMC Veterinary Research Nov 2022Gram-negative bacterial infections are a serious problem in beef and dairy cattle. Bacterial outer membrane proteins (OMPs) play a pivotal role in cellular survival and...
BACKGROUND
Gram-negative bacterial infections are a serious problem in beef and dairy cattle. Bacterial outer membrane proteins (OMPs) play a pivotal role in cellular survival and the host-bacterium interaction. Histophilus somni OMP40 was identified as a porin with homology between its N-terminal amino acid sequence and the sequences of porins of other gram-negative bacteria The aim of this study was to produce recombinant H. somni OMP40 (rOMP40), optimize its production and evaluate its immunogenic properties in calves. The cross-reactivity of anti-rOMP40 antibodies were also checked.
RESULTS
The highest overexpression of rOMP40 was demonstrated by Escherichia coli C41 using the autoinduction process. Double immunization of calves (20 μg rOMP40 per animal) induced a significant increase of anti-rOMP40 antibodies in the IgG (P ≤ 0.01) and IgG (P ≤ 0.01, after first immunization only) subclasses, but not IgM. ELISA revealed increased reactivity of the IgG against surface antigens of E. coli and Pasteurella multocida after the second immunization (P < 0.01). Cross reactivity of anti-rOMP40 antibodies with ~ 40 kDa antigens of most common gram-negative pathogens was shown by Western blotting.
CONCLUSION
Immunization with H. somni rOMP40 induced a humoral response in cattle with broad cross-reactivity with similar antigens of other species of Pasteurellaceae and Enterobacteriaceae families and the delayed-type hypersensitivity reaction. The obtained results encourage further study to evaluate the protective effect of the produced protein as a subunit vaccine in cattle.
Topics: Cattle; Animals; Escherichia coli; Antibody Formation; Pasteurellaceae; Recombinant Proteins; Bacterial Outer Membrane Proteins; Immunoglobulin G
PubMed: 36401280
DOI: 10.1186/s12917-022-03515-x -
Journal of Animal Science Nov 2022Experimental bovine respiratory syncytial virus (BRSV) infection can enhance Histophilus somni (Hs) disease in calves; we thus hypothesized that modified-live virus...
Experimental bovine respiratory syncytial virus (BRSV) infection can enhance Histophilus somni (Hs) disease in calves; we thus hypothesized that modified-live virus (MLV) vaccines containing BRSV may alter Hs carriage. Our objective was to determine the effects of an intranasal (IN) trivalent (infectious bovine rhinotracheitis virus [IBRV], parainfluenza-3 virus [PI3V], and BRSV) respiratory vaccine with parenteral (PT) bivalent bovine viral diarrhea virus (BVDV) type I + II vaccine, or a PT pentavalent (BVDV type I and II, IBRV, BRSV, and PI3V) respiratory vaccine, on health, growth, immunity, and nasal pathogen colonization in high-risk beef calves. Calves (n = 525) were received in five truckload blocks and stratified by body weight (213 ± 18.4 kg), sex, and presence of a pre-existing ear-tag. Pens were spatially arranged in sets of three within a block and randomly assigned to treatment with an empty pen between treatment groups consisting of: 1) no MLV respiratory vaccination (CON), 2) IN trivalent MLV respiratory vaccine with PT BVDV type I + II vaccine (INT), or 3) PT pentavalent, MLV respiratory vaccine (INJ). The pen was the experimental unit, with 15 pens/treatment and 11 to 12 calves/pen in this 70-d receiving study. Health, performance, and BRSV, Hs, Mycoplasma bovis (Mb), Mannheimia haemolytica (Mh), and Pasteurella multocida (Pm) level in nasal swabs via rtPCR was determined on days 0, 7, 14, and 28, and BRSV-specific serum neutralizing antibody titer, and serum IFN-γ concentration via ELISA, were evaluated on days 0, 14, 28, 42, 56, and 70. Morbidity (P = 0.83), mortality (P = 0.68) and average daily gain (P ≥ 0.82) did not differ. Serum antibodies against BRSV increased with time (P < 0.01). There was a treatment × time interaction (P < 0.01) for Hs detection; on days 14 and 28, INT (21.1% and 57.1%) were more frequently (P < 0.01) Hs positive than CON (3.6% and 25.3%) or INJ (3.4 % and 8.4%). Also, INT had reduced (P = 0.03) cycle time of Hs positive samples on day 28. No difference (P ≥ 0.17) was found for IFN-γ concentration and Mb, Mh, or Pm detection. The proportion of Mh positive culture from lung specimens differed (P < 0.01); INT had fewer (0.0%; 0 of 9) Mh positive lungs than INJ (45.5%; 6 of 13) or CON (74.0%; 14 of 19). Vaccination of high-risk calves with MLV did not clearly impact health or growth during the receiving period. However, INT was associated with an altered upper respiratory microbial community in cattle resulting in increased detection and level of Hs.
Topics: Cattle; Animals; Viral Vaccines; Antibodies, Viral; Respiratory Syncytial Virus, Bovine; Vaccines, Attenuated; Herpesvirus 1, Bovine; Diarrhea Viruses, Bovine Viral; Mannheimia haemolytica; Cattle Diseases; Pasteurella multocida
PubMed: 35926833
DOI: 10.1093/jas/skac249 -
The Journal of Antimicrobial... Sep 2023
Topics: Mannheimia haemolytica; Anti-Bacterial Agents; Drug Resistance, Bacterial; Macrolides; Pasteurella multocida
PubMed: 37533327
DOI: 10.1093/jac/dkad209 -
Microbiology Spectrum Jun 2023Avibacterium paragallinarum is the pathogen involved in infectious coryza (IC), an acute infectious upper respiratory disease in chickens. The prevalence of IC has...
Avibacterium paragallinarum is the pathogen involved in infectious coryza (IC), an acute infectious upper respiratory disease in chickens. The prevalence of IC has increased in China in recent years. There is a lack of reliable and effective procedures for gene manipulation, which has limited the research on the bacterial genetics and pathogenesis of A. paragallinarum. Natural transformation has been developed as a method of gene manipulation in by the introduction of foreign genes or DNA fragments into bacterial cells, but there has been no report on natural transformation in . In this study, we analyzed the existence of homologous genetic factors and competence proteins underlying natural transformation in and established a method for transformation in it. Through bioinformatics analysis, we identified 16 homologs of Haemophilus influenzae competence proteins in . We found that the uptake signal sequence (USS) was overrepresented in the genome of (1,537 to 1,641 copies of the core sequence ACCGCACTT). We then constructed a plasmid, pEA-KU, that carries the USS and a plasmid, pEA-K, without the USS. These plasmids can be transferred via natural transformation into naturally competent strains of . Significantly, the plasmid that carries USS showed a higher transformation efficiency. In summary, our results demonstrate that has the ability to undergo natural transformation. These findings should prove to be a valuable tool for gene manipulation in . Natural transformation is an important mechanism for bacteria to acquire exogenous DNA molecules during the process of evolution. Additionally, it can also be used as a method to introduce foreign genes into bacteria under laboratory conditions. Natural transformation does not require equipment such as an electroporation apparatus. It is easy to perform and is similar to gene transfer under natural conditions. However, there have been no reports on natural transformation in Avibacterium paragallinarum. In this study, we analyzed the presence of homologous genetic factors and competence proteins underlying natural transformation in . Our results indicate that natural competence could be induced in serovars A, B, and C. Furthermore, the method that we established to transform plasmids into naturally competent strains was stable and efficient.
Topics: Animals; Haemophilus Infections; Poultry Diseases; Chickens; Pasteurellaceae; Haemophilus paragallinarum
PubMed: 37212663
DOI: 10.1128/spectrum.05209-22 -
ACS Infectious Diseases Feb 2024is a commensal of the human upper respiratory tract that can infect diverse host niches due, at least in part, to its ability to withstand both endogenous and...
is a commensal of the human upper respiratory tract that can infect diverse host niches due, at least in part, to its ability to withstand both endogenous and host-mediated oxidative stresses. Here, we show that , a gene previously linked to iron import, is essential for manganese recruitment the HfeBCD transporter. Structural analyses show that metal binding in HfeA uses a unique mechanism that involves substantial rotation of the C-terminal lobe of the protein. Disruption of reduced manganese acquisition and was associated with decreased growth under aerobic conditions, impaired manganese-superoxide dismutase activity, reduced survival in macrophages, and changes in biofilm production in the presence of superoxide. Collectively, this work shows that HfeA contributes to manganese acquisition and virulence attributes. High conservation of the permease in species suggests that it may serve similar roles in other pathogenic Pasteurellaceae.
Topics: Humans; Haemophilus influenzae; Membrane Transport Proteins; Manganese; Biofilms; Homeostasis
PubMed: 38240689
DOI: 10.1021/acsinfecdis.3c00407 -
Veterinary Microbiology Jul 2022Histophilus somni is a prevalent commensal organism of the upper respiratory tract of cattle and a major causative agent of bovine respiratory disease (BRD) and other... (Review)
Review
Histophilus somni is a prevalent commensal organism of the upper respiratory tract of cattle and a major causative agent of bovine respiratory disease (BRD) and other syndromes including myocarditis and infectious thromboembolic meningoencephalitis. This study investigated the antimicrobial susceptibility and phylogenetic relationships of H. somni isolates obtained from lung, heart, and other tissues at post-mortem as well as nasal mucosa swabs from cases of BRD in Australian feedlots (2004-2019). Broth microdilution Minimal Inhibitory Concentration (MIC) assays were determined for 19 antimicrobials using three different media (CLSI approved Veterinary Fastidious Medium [VFM], Mueller-Hinton fastidious broth medium supplemented with yeast extract [MHF-Y] and Columbia Broth [CB] supplemented with 5% lysed horse blood). For all antimicrobials, MICs obtained using CB medium were identical or within 1 dilution step of the MICs obtained for VFM and MHF-Y media. Therefore, CB may be a suitable medium for H. somni antimicrobial susceptibility testing similar to MHF-Y medium. None of the 70 Australian H. somni isolates exhibited resistance to antimicrobials with CLSI breakpoints including those commonly used in the treatment of BRD in Australia (first-line tetracyclines [chlortetracycline and oxytetracycline], second-line macrolides [tulathromycin], and third-line extended-spectrum cephalosporin [ceftiofur]). Whole-genome sequence analysis of 65 H. somni isolates for genomic single nucleotide polymorphism differences identified four phylogenetic clusters, each containing isolates from different Australian states, feedlots and tissue sources that clustered together. These findings demonstrate limited genetic diversity and the absence of significant antimicrobial resistance among Australian isolates of H. somni isolated from feedlot cattle.
Topics: Animals; Anti-Bacterial Agents; Australia; Cattle; Cattle Diseases; Genomics; Horse Diseases; Horses; Pasteurellaceae; Phylogeny; Respiratory System; Respiratory Tract Diseases
PubMed: 35640408
DOI: 10.1016/j.vetmic.2022.109460 -
Respiratory Physiology & Neurobiology Sep 2023Pasteurella (P.) multocida commonly occurs in the upper respiratory tract of healthy domestic pets, especially cats and dogs. People become infected by biting,...
BACKGROUND
Pasteurella (P.) multocida commonly occurs in the upper respiratory tract of healthy domestic pets, especially cats and dogs. People become infected by biting, scratching or direct contact with the animal's saliva. Inflammation develops in the wound and limits itself to the skin and subcutaneous tissue. P. multocida may cause respiratory tract infections and severe life-threatening complications. The study aimed to identify the lower respiratory infection in humans caused by P. multocida, to determine the potential source of infection and the associated symptoms, comorbidities and applied treatment.
MATERIALS AND METHODS
Between January 2010 and September 2021, 14,258 patients underwent 16,255 routine flexible video bronchoscopy (FVB), and the same number of bronchoalveolar lavage fluid (BALF) samples for microbiological examination were taken.
RESULTS
Microbiological examinations of the BALF only allowed the identification of six patients with P. multocida infection. All persons reported multiple scratches or bites and licking or kissing by their pets in the past. Productive cough with expectoration of mucopurulent discharge was the predominant symptom.
CONCLUSIONS
A lower respiratory infection caused by P. multocida is not common in humans. It should be considered particularly in elderly patients with underlying diseases and exposure to cats and dogs.
Topics: Humans; Animals; Cats; Dogs; Aged; Pasteurella multocida; Pasteurella Infections; Pasteurella; Respiratory Tract Infections; Saliva
PubMed: 37331420
DOI: 10.1016/j.resp.2023.104091 -
International Journal of Systematic and... Oct 2023Forty-one isolates of Bisgaard taxon 6 obtained from guinea pigs, pandas, pigs and muskrat and isolates of taxon 10 from horses and horse bites in humans were subjected...
Forty-one isolates of Bisgaard taxon 6 obtained from guinea pigs, pandas, pigs and muskrat and isolates of taxon 10 from horses and horse bites in humans were subjected phenotypic characterization. Production of acid from (-)-d-mannitol, (-)-d-sorbitol and (+)-d-glycogen separated taxon 10 (positive) from taxon 6 (negative), while from two to 11 phenotypic characteristics separated taxa 6 and 10 from the 32 genera of reported so far. Forty-four strains were genetically characterized. Sequencing of 16S rRNA genes documented a monophyletic relationship at the species level and the highest 16S rRNA gene sequence similarity of 95.6 % to other species was found between strain CCUG 15568 and the type strain of (CCUG 38457). Digital DNA-DNA hybridization (dDDH) values predicted from whole genomic sequences between CCUG 15568 and other characterized strains of taxa 6 and 10 were 69.3-99.9 %. The average nucleotide identity values were higher than 95 % for all strains. The highest dDDH value of 29 % outside the taxa 6 and 10 group was obtained with the genome of the type strain of [] , indicating a separate taxonomic status at species level to taxa 6 and 10. The phylogenetic comparison of concatenated conserved protein sequences showed the unique position of the taxa investigated in the current study which qualified for the status of a new genus since the highest identity was found with with 79 %, well below the upper threshold between genera of 85 %. Based upon the low genetic similarity to other genera of the family and a unique phenotype, we suggest that Bisgaard taxa 6 and 10 should be classified as gen. nov., sp. nov. The G+C of the type strain of , 8.5 (=CCUG 15568=DSM 115565), is 46.2 mol%, calculated from the whole genome.
Topics: Humans; Animals; Guinea Pigs; Horses; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; DNA, Bacterial; Bacterial Typing Techniques; Base Composition; Fatty Acids; Pasteurellaceae
PubMed: 37882672
DOI: 10.1099/ijsem.0.006092