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Infection, Genetics and Evolution :... Jun 2020Haemophilus influenzae remains a common cause of illness in children worldwide. H. influenzae type b is the leading cause of bacterial meningitis in children before... (Review)
Review
Haemophilus influenzae remains a common cause of illness in children worldwide. H. influenzae type b is the leading cause of bacterial meningitis in children before introduction of vaccination and is a common cause of pneumonia, epiglottis and septic arthritis. Since the implementation of the Hib conjugate vaccine, the non-typeable H. influenzae has rapidly decreased in respiratory and invasive infections in children and adults. However, the rate of antibiotic resistance of H. influenzae varies with region and period and is usually on the rise. In this review, typing of H. influenzae, virulence factors and resistance will be dissertated.
Topics: Anti-Bacterial Agents; Biofilms; Drug Resistance, Bacterial; Evolution, Molecular; Haemophilus Infections; Haemophilus influenzae; Haemophilus influenzae type b; Humans; Molecular Epidemiology; Polysaccharides, Bacterial; Serotyping; Virulence; Virulence Factors; beta-Lactam Resistance
PubMed: 31981610
DOI: 10.1016/j.meegid.2020.104205 -
Microbiology Spectrum May 2018Members of the highly heterogeneous family cause a wide variety of diseases in humans and animals. Antimicrobial agents are the most powerful tools to control such... (Review)
Review
Members of the highly heterogeneous family cause a wide variety of diseases in humans and animals. Antimicrobial agents are the most powerful tools to control such infections. However, the acquisition of resistance genes, as well as the development of resistance-mediating mutations, significantly reduces the efficacy of the antimicrobial agents. This article gives a brief description of the role of selected members of the family in animal infections and of the most recent data on the susceptibility status of such members. Moreover, a review of the current knowledge of the genetic basis of resistance to antimicrobial agents is included, with particular reference to resistance to tetracyclines, β-lactam antibiotics, aminoglycosides/aminocyclitols, folate pathway inhibitors, macrolides, lincosamides, phenicols, and quinolones. This article focusses on the genera of veterinary importance for which sufficient data on antimicrobial susceptibility and the detection of resistance genes are currently available (, , , , and ). Additionally, the role of plasmids, transposons, and integrative and conjugative elements in the spread of the resistance genes within and beyond the aforementioned genera is highlighted to provide insight into horizontal dissemination, coselection, and persistence of antimicrobial resistance genes. The article discusses the acquisition of diverse resistance genes by the selected members from other Gram-negative or maybe even Gram-positive bacteria. Although the susceptibility status of these members still looks rather favorable, monitoring of their antimicrobial susceptibility is required for early detection of changes in the susceptibility status and the newly acquired/developed resistance mechanisms.
Topics: Animal Diseases; Animals; Anti-Bacterial Agents; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Pasteurellaceae; Pasteurellaceae Infections
PubMed: 29916344
DOI: 10.1128/microbiolspec.ARBA-0022-2017 -
Hypertension Research : Official... Apr 2017There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in... (Review)
Review
There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.
Topics: Aggregatibacter actinomycetemcomitans; Animals; Bacteroidaceae Infections; Cardiomegaly; Disease Models, Animal; Humans; Mice; Pasteurellaceae Infections; Periodontitis; Porphyromonas gingivalis
PubMed: 27829660
DOI: 10.1038/hr.2016.146 -
Current Topics in Microbiology and... 2016Histophilus somni was proposed in 2003 as a common name for bacteria that earlier had been called "Haemophilus somni", "Haemophilus agni", "Haemophilus somnifer", and... (Review)
Review
Histophilus somni was proposed in 2003 as a common name for bacteria that earlier had been called "Haemophilus somni", "Haemophilus agni", "Haemophilus somnifer", and "Histophilus ovis". The species is clearly separated from other species and genera within the family Pasteurellaceae. The species is phenotypically variable, but highly uniform regarding the 16S rDNA sequence. Whole-genome sequencing has revealed distinct genetic differences between a commensal and a pathogenic strain, particularly in regard to putative virulence factors. However, broad generalizations regarding the genetics of H. somni cannot be applied to the entire species until the genomes of additional strains are sequenced.
Topics: Pasteurellaceae; Phylogeny; Sequence Analysis, DNA
PubMed: 26847356
DOI: 10.1007/82_2015_5007 -
Current Topics in Microbiology and... 2016The pathogen surface is usually the first site of interaction with the host. Histophilus somni was earlier thought to only have an outer membrane on its surface. Now it... (Review)
Review
The pathogen surface is usually the first site of interaction with the host. Histophilus somni was earlier thought to only have an outer membrane on its surface. Now it is known that the surface is composed of many virulence factors, including outer membrane proteins, lipooligosaccharide or endotoxin, a fibrillar network, and an exopolysaccharide. Outer membrane blebs, endotoxin, the fibrillar network, and the exopolysaccharide are also shed from the surface. This review will focus on the surface proteins of this pathogen that may colonize the mucosal surface of ruminants as a commensal or may cause pneumonia, septicemia, myocarditis, thrombotic meningoencephalitis, arthritis, and/or abortion. The major outer membrane protein has been well studied. Since its size and epitopes vary from strain to strain, it may be useful for typing strains. Iron-regulated OMPs have also received much attention because of their role in iron uptake for in vivo growth of H. somni. Other OMPs may be protective, based on passive immunization with monospecific antibodies and active immunization experiments. The surface and shed fibrillar network has been shown to be an immunoglobulin-binding protein in that it binds bovine IgG2 by the Fc portion. Two repeat domains (DR1 and DR2) have cytotoxic Fic motifs. Vaccine studies with recombinant DR2 are promising. Studies of the bacterial genome as well as comparison of surface proteins of different strains from the various H. somni syndromes and carrier states will be discussed and have provided much insight into pathogenesis and protection.
Topics: Animals; Bacterial Outer Membrane Proteins; Cattle; Pasteurellaceae
PubMed: 26728061
DOI: 10.1007/82_2015_5011 -
Current Topics in Microbiology and... 2016Histophilus somni is a commensal and an opportunistic bacterial pathogen associated with multisystemic diseases in cattle and sheep. Some strains of H. somni isolated... (Review)
Review
Histophilus somni is a commensal and an opportunistic bacterial pathogen associated with multisystemic diseases in cattle and sheep. Some strains of H. somni isolated from the genital tract of cattle are biochemically and serologically similar to the pathogenic strains, but are relatively innocuous. Several virulence factors/mechanisms have been identified in H. somni, of which the phase-variable lipooligosaccharide, induction of apoptosis of host cells, intraphagocytic survival, and immunoglobulin Fc-binding proteins have been well characterized. The genomes of H. somni pneumonia strain 2336 and preputial strain 129Pt have also been sequenced, and comparative analyses of these genomes have provided novel insights into the role of horizontal gene transfer in the evolution of the respective strains. Continued analyses of the genomes of H. somni strains and comparing them to the newly sequenced genomes of other bacteria facilitated the identification of a putative integrative and conjugative element (designated ICEHso2336) encoding tetracycline resistance. Comparative genomics also showed that the uptake signal sequence (5'-AAGTGCGGT) of Haemophilus influenzae is abundant in H. somni and provided a genetic basis for the recalcitrance of some strains of this species to natural transformation. The post-genomic era for H. somni offered an opportunity for the functional characterization of genes identified by computational methods. This opportunity has been realized to a great extent by transcriptomic studies that have identified several small noncoding RNAs and new genes. These new discoveries and developments are expected to stimulate further in-depth investigations of H. somni, especially from the systems biology viewpoint.
Topics: Base Sequence; Genomics; Molecular Sequence Data; Mutagenesis; Pasteurellaceae; Plasmids; Transcriptome
PubMed: 26728065
DOI: 10.1007/82_2015_5009 -
The American Journal of Medicine Dec 2018
Topics: Cardiac Tamponade; Haemophilus influenzae; Humans
PubMed: 30509391
DOI: 10.1016/j.amjmed.2018.07.044 -
Molecular Oral Microbiology Oct 2016The QseBC two-component system (TCS) is associated with quorum sensing and functions as a global regulator of virulence. Based on sequence similarity within the sensor... (Review)
Review
The QseBC two-component system (TCS) is associated with quorum sensing and functions as a global regulator of virulence. Based on sequence similarity within the sensor domain and conservation of an acidic motif essential for signal recognition, QseBC is primarily distributed in the Enterobacteriaceae and Pasteurellaceae. In Escherichia coli, QseC responds to autoinducer-3 and/or epinephrine/norepinephrine. Binding of epinephrine/norepinephrine is inhibited by adrenergic antagonists; hence QseC functions as a bacterial adrenergic receptor. Aggregatibacter actinomycetemcomitans QseC is activated by a combination of epinephrine/norepinephrine and iron, whereas only iron activates the Haemophilus influenzae sensor. QseC phosphorylates QseB but there is growing evidence that QseB is activated by non-cognate sensors and regulated by dephosphorylation via QseC. Interestingly, the QseBC signaling cascades and regulons differ significantly. In enterohemorrhagic E. coli, QseC induces expression of a second adrenergic TCS and phosphorylates two non-cognate response regulators, each of which induces specific sets of virulence genes. This signaling pathway integrates with other regulatory mechanisms mediated by transcriptional regulators QseA and QseD and a fucose-sensing TCS and likely controls the level and timing of virulence gene expression. In contrast, A. actinomycetemcomitans QseC signals through QseB to regulate genes involved in anaerobic metabolism and energy production, which may prime cellular metabolism for growth in an anaerobic host niche. QseC represents a novel target for therapeutic intervention and small molecule inhibitors already show promise as broad-spectrum antimicrobials. Further characterization of QseBC signaling may identify additional differences in QseBC function and inform further development of new therapeutics to control microbial infections.
Topics: Aggregatibacter actinomycetemcomitans; Bacterial Proteins; Enterobacteriaceae; Escherichia coli Proteins; Gene Expression Regulation, Bacterial; Operon; Pasteurellaceae; Phosphorylation; Promoter Regions, Genetic; Quorum Sensing; Receptors, Adrenergic; Regulon; Signal Transduction; Trans-Activators; Virulence
PubMed: 26426681
DOI: 10.1111/omi.12138 -
Acta Veterinaria Hungarica Sep 2020The occurrence of members of the Pasteurellaceae and Neisseriaceae families was studied in dogs and cats. A total of 110 nasal and pharyngeal swab samples from 47 dogs...
The occurrence of members of the Pasteurellaceae and Neisseriaceae families was studied in dogs and cats. A total of 110 nasal and pharyngeal swab samples from 47 dogs and 8 cats were collected. Most of the strains were identified by 16S rDNA sequencing, except Frederiksenia canicola and Pasteurella multocida where species-specific polymerase chain reactions were applied. The most frequently isolated species was F. canicola, which occurred only in dogs, mainly in the pharyngeal cavity. The second commonest bacterium, P. multocida was found in both types of samples and in both hosts. Other species from the family Pasteurellaceae, such as Haemophilus haemoglobinophilus, Pasteurella canis and P. dagmatis, were detected only in dogs. All isolated species belonging to the family Neisseriaceae, mainly representing Neisseria weaveri, were found only in the pharyngeal cavity. Neisseria weaveri and N. zoodegmatis could be detected in both hosts. Neisseria dumasiana and N. canis were isolated from dogs, while N. shayeganii only from a cat. For phylogenetic analysis, rpoB gene sequencing was performed, where the strains were on monophyletic branches and clearly separated from each other. In this study, recently described species such as F. canicola, N. shayeganii and N. dumasiana were detected that had never been isolated in Hungary before.
Topics: Animals; Cat Diseases; Cats; Dog Diseases; Dogs; Gram-Negative Bacterial Infections; Hungary; Incidence; Microbiota; Neisseriaceae; Pasteurellaceae; Pasteurellaceae Infections; Pharynx; Respiratory System; Respiratory Tract Diseases
PubMed: 33141116
DOI: 10.1556/004.2020.00036 -
Tropical Animal Health and Production Oct 2023Gallibacterium anatis (G. anatis), a member of the Pasteurellaceae family, normally inhabits the upper respiratory and lower genital tracts of poultry. However, under... (Review)
Review
Gallibacterium anatis (G. anatis), a member of the Pasteurellaceae family, normally inhabits the upper respiratory and lower genital tracts of poultry. However, under certain circumstances of immunosuppression, co-infection (especially with Escherichia coli or Mycoplasma), or various stressors, G. anatis caused respiratory, reproductive, and systemic diseases. Infection with G. anatis has emerged in different countries worldwide. The bacterium affects mainly chickens; however, other species of domestic and wild birds may get infected. Horizontal, vertical, and venereal routes of G. anatis infection have been reported. The pathogenicity of G. anatis is principally related to the presence of some essential virulence factors such as Gallibacterium toxin A, fimbriae, haemagglutinin, outer membrane vesicles, capsule, biofilms, and protease. The clinical picture of G. anatis infection is mainly represented as tracheitis, oophoritis, salpingitis, and peritonitis, while other lesions may be noted in cases of concomitant infection. Control of such infection depends mainly on applying biosecurity measures and vaccination. The antimicrobial sensitivity test is necessary for the correct treatment of G. anatis. However, the development of multiple drug resistance is common. This review article sheds light on G. anatis regarding history, susceptibility, dissemination, virulence factors, pathogenesis, clinical picture, diagnosis, and control measures.
Topics: Female; Animals; Poultry; Chickens; Pasteurellaceae Infections; Pasteurellaceae; Virulence Factors; Escherichia coli; Poultry Diseases
PubMed: 37889324
DOI: 10.1007/s11250-023-03796-w