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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 -
Canadian Journal of Veterinary Research... Apr 1990With the exception of a few consistent pathogens--Pasteurella multocida strains of bovine hemorrhagic septicemia and fowl cholera, Actinobacillus (Haemophilus)... (Review)
Review
With the exception of a few consistent pathogens--Pasteurella multocida strains of bovine hemorrhagic septicemia and fowl cholera, Actinobacillus (Haemophilus) pleuropneumoniae, Haemophilus aegyptius and Haemophilus paragallinarum--members of the family Pasteurellaceae are commensal parasites on mucous membranes of vertebrate animals. Many have pathogenic potential, which becomes manifest under conditions of immunodeficiency and stress. Pathogenesis (except in porcine atrophic rhinitis) depends on mobilization of inflammatory responses probably in large part by endotoxin with contributions from protein toxins, which interfere with leukocyte activity and, by their cytotoxicity, cause exacerbation of the inflammatory reaction. Disease patterns include pneumonic/septicemic, upper respiratory and local/traumatic. Acquired resistance is chiefly antibody-dependent, and, with current and emerging biotechnical resources, stands a good chance of being artificially achievable for many important diseases attributed to Pasteurellaceae.
Topics: Animals; Bacterial Infections; Pasteurellaceae
PubMed: 2193710
DOI: No ID Found -
FEMS Microbiology Reviews Apr 1998The ability of bacteria to adhere to mucosal epithelium is dependent on the expression of adhesive molecules or structures, called adhesins, that allow attachment of the... (Review)
Review
The ability of bacteria to adhere to mucosal epithelium is dependent on the expression of adhesive molecules or structures, called adhesins, that allow attachment of the organisms to complementary molecules on mucosal surfaces, the receptors. Important human and animal pathogens are found among the Pasteurellaceae family which includes Haemophilus, Actinobacillus, and Pasteurella organisms. The purpose of this paper is to review the adhesin-receptor systems found in Pasteurellaceae, with an emphasis on recent developments in this specific area. Most of these organisms can employ multiple molecular mechanisms of adherence (or multiple adhesins) to initiate infection. Indeed, a wide variety of adhesins are expressed by members of the Pasteurellaceae, and different proteins (e.g. fimbriae, fibrils, outer membrane proteins) as well as polysaccharides (lipooligosaccharides, lipopolysaccharides, capsular polysaccharides) were clearly shown to play an important role in adherence. In many instances, these adhesins have proved to represent good vaccine candidates. Surprisingly, the receptors on host mucosal surfaces have yet been identified in very few cases.
Topics: Adhesins, Bacterial; Bacterial Adhesion; Extracellular Matrix Proteins; Humans; Mucus; Pasteurellaceae
PubMed: 9640646
DOI: 10.1016/s0168-6445(98)00007-2 -
International Journal of Medical... Sep 2002RTX toxins (repeats in the structural toxin) are pore-forming protein toxins produced by a broad range of pathogenic Gram-negative bacteria. In vitro, RTX toxins mostly... (Review)
Review
RTX toxins (repeats in the structural toxin) are pore-forming protein toxins produced by a broad range of pathogenic Gram-negative bacteria. In vitro, RTX toxins mostly exhibit a cytotoxic and often also a hemolytic activity. They are particularly widespread in species of the family Pasteurellaceae which cause infectious diseases, most frequently in animals but also in humans. Most RTX toxins are proteins with a molecular mass of 100-200 kDa and are post-translationally activated by acylation via a specific activator protein. The repeated structure of RTX toxins, which gave them their name, is composed of iterative glycine-rich nonapeptides binding Ca2+ on the C-terminal half of the protein. Genetic analysis of RTX toxins of various species of Pasteurellaceae and of a few other Gram-negative bacteria gave evidence of horizontal transfer of genes encoding RTX toxins and led to speculations that RTX toxins might have originated from Pasteurellaceae. The toxic activities of RTX toxins in host cells may lead to necrosis and apoptosis and the underlying detailed mechanisms are currently under investigation. The impact of RTX toxins in pathogenicity and the immune responses of the host were described for several species of Pasteurellaceae. Neutralizing antibodies were shown to significantly reduce the cytotoxic activity of RTX toxins. They constitute a valuable strategy in the development of immuno-prophylactics against several animal diseases caused by pathogenic species of Pasteurellaceae. Although many RTX toxins possess cytotoxic and hemolytic activities toward a broad range of cells and erythrocytes, respectively, a few RTX toxins were shown to have cytotoxic activity only against cells of specific hosts and/or show cell-type specificity. Further evidence exists that RTX toxins play a potential role in host specificity of certain pathogens.
Topics: Animals; Bacterial Toxins; Gram-Negative Bacterial Infections; Humans; Pasteurellaceae; Phylogeny; Virulence
PubMed: 12398206
DOI: 10.1078/1438-4221-00200 -
Zentralblatt Fur Bakteriologie :... Jun 1993The reservoir of eighty-one taxa/groups classified with the family Pasteurellaceae Pohl 1981 is reviewed based upon published data and own investigations. With the... (Review)
Review
The reservoir of eighty-one taxa/groups classified with the family Pasteurellaceae Pohl 1981 is reviewed based upon published data and own investigations. With the exception of certain strains of P. multocida, A. pleuropneumoniae and [H.] paragallinarum organisms belonging to this family are usually regarded as opportunistic, secondary invaders which under normal conditions coexist peacefully with the animal host on mucosal membranes of the upper respiratory- and lower genital tracts. Very little is known about factors that govern the ecological preferences that certain members of this family show for specific surfaces and hosts. Mechanisms of colonization, survival and multiplication, invasion and pathogenic action are incompletely understood. The significance of Pasteurellaceae in animals and man has recently been reviewed. Subsequent publications have underlined the significance of biovars 2 of P. canis and P. avium and ornithine negative P. multocida in pneumonia in cattle. In addition, differences in pathogenicity have been demonstrated for different serovars of [H.] parasuis. The disease potential of many taxa/groups is only incompletely known.
Topics: Actinobacillus; Actinobacillus Infections; Animals; Haemophilus; Haemophilus Infections; Humans; Opportunistic Infections; Pasteurella; Pasteurella Infections; Pasteurellaceae; Pasteurellaceae Infections; Virulence
PubMed: 8369587
DOI: 10.1016/s0934-8840(11)80487-1 -
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 -
Veterinary Microbiology Nov 2011RTX toxins are bacterial pore-forming toxins that are particularly abundant among pathogenic species of Pasteurellaceae, in which they play a major role in virulence.... (Review)
Review
RTX toxins are bacterial pore-forming toxins that are particularly abundant among pathogenic species of Pasteurellaceae, in which they play a major role in virulence. RTX toxins of several primary pathogens of the family of Pasteurellaceae are directly involved in causing necrotic lesions in the target organs. Many RTX toxins are known as haemolysins because they lyse erythrocytes in vitro, an effect that is non-specific, but which serves as a useful marker in bacteriological identification and as an easily measurable signal in vitro in experimental studies. More recent studies have shown that the specific targets of most RTX toxins are leukocytes, with RTX toxins binding to the corresponding β-subunit (CD18) of β2 integrins and then exerting cytotoxic activity. After uptake by the target cell, at sub-lytic concentrations, some RTX toxins are transported to mitochondria and induce apoptosis. For several RTX toxins the binding to CD18 has been shown to be host specific and this seems to be the basis for the host range specificity of these RTX toxins. Observations on two very closely related species of the Pasteurellaceae family, Actinobacillus suis, a porcine pathogen particularly affecting suckling pigs, and Actinobacillus equuli subsp. haemolytica, which causes pyosepticaemia in new-born foals (sleepy foal disease), have revealed that they express different RTX toxins, named ApxI/II and Aqx, respectively. These RTX toxins are specifically cytotoxic for porcine and equine leukocytes, respectively. Furthermore, the ApxI and Aqx toxins of these species, when expressed in an isogenetic background in Escherichia coli, are specifically cytotoxic for leukocytes of their respective hosts. These data indicate the determinative role of RTX toxins in host specificity of pathogenic species of Pasteurellaceae.
Topics: Actinobacillus Infections; Actinobacillus equuli; Animals; Bacterial Toxins; Hemolysin Proteins; Horses; Host Specificity; Pasteurellaceae; Pasteurellaceae Infections; Swine; Virulence
PubMed: 21645978
DOI: 10.1016/j.vetmic.2011.05.018 -
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 -
Zentralblatt Fur Bakteriologie :... Jun 1993Within the last decade new knowledge has emerged concerning the significance of Pasteurellaceae in man; the classification has undergone some changes, and new taxa were... (Review)
Review
Within the last decade new knowledge has emerged concerning the significance of Pasteurellaceae in man; the classification has undergone some changes, and new taxa were described. Haemophilus influenzae serotype b was shown to have a clonal distribution that is related to demographic patterns of the human host. Brazilian purpuric fever is caused by a special clone of Haemophilus aegyptius. H. influenzae biotype IV seems to be a genital pathogen, and may deserve species rank. New Pasteurella species have been described, that occur in well known pathological foci in man, e.g. bite wounds. Toxigenic P. multocida may occur in man also; the significance of toxigenicity in man is not known. The real actinobacilli of man, A. ureae and A. hominis are still very rarely reported. In order to avoid wrong epidemiological conclusions, correct diagnosis is emphasized.
Topics: Actinobacillus; Actinobacillus Infections; Carrier State; Female; Haemophilus; Haemophilus Infections; Humans; Male; Pasteurella; Pasteurella Infections; Pasteurellaceae; Pasteurellaceae Infections; Virulence
PubMed: 8369585
DOI: 10.1016/s0934-8840(11)80488-3 -
Oral Microbiology and Immunology Dec 1993Many members of the Actinobacillus-Haemophilus-Pasteurella group (family Pasteurellaceae) have been misclassified. This article reviews the chemotaxonomic characters... (Review)
Review
Many members of the Actinobacillus-Haemophilus-Pasteurella group (family Pasteurellaceae) have been misclassified. This article reviews the chemotaxonomic characters that recently have been provided to improve the taxonomy of Pasteurellaceae. These include fatty acids of whole cells, of lipopolysaccharides and of single colonies, together with sugar contents of whole cells, of whole defatted cells, of lipopolysaccharides and of single colonies. This article also reviews taxonomy aided by distribution of proteins in whole cells and outer membranes, distribution of enzymes in outer membrane vesicles and in whole cells, bacteriolysis induced by ethylenediaminetetraacetic acid and hen eggwhite lysozyme and the distribution of respiratory quinones. Furthermore, an overview of characters obtained through studies on genetic transformation, restriction enzyme analysis, restriction fragment length polymorphism, DNA-DNA hybridization, DNA-rRNA hybridization, and 16S rRNA sequencing is given.
Topics: Aggregatibacter actinomycetemcomitans; Bacterial Proteins; Bacterial Typing Techniques; DNA, Bacterial; Fatty Acids; Haemophilus; Pasteurellaceae; Phylogeny; Polysaccharides, Bacterial; RNA, Bacterial
PubMed: 7512257
DOI: 10.1111/j.1399-302x.1993.tb00607.x