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Current Topics in Microbiology and... 2016The biofilm matrix of Histophilus somni is a complex architecture that differs substantially in structure between a pathogenic and commensal isolate examined. Overall,... (Review)
Review
The biofilm matrix of Histophilus somni is a complex architecture that differs substantially in structure between a pathogenic and commensal isolate examined. Overall, most pathogenic isolates produce more biofilm than commensal isolates. A major component of the biofilm is exopolysaccharide (EPS), which is also produced in greater quantity in the pathogenic isolate than in the commensal isolate studied. The EPS is composed of a D-mannan polymer, with occasional galactose residues present on side chains, similar in composition to that of yeast mannan. When grown in the presence of sialic acid, the biofilm EPS becomes sialylated and the amino sugars N-acetylglucosamine and N-acetylgalactosamine can be detected. In vitro biofilm formation follows a typical 4-stage growth curve, characterized by attachment, growth, maturation, and detachment. Following experimental challenge, formation of an H. somni biofilm has been demonstrated in cardiopulmonary tissue, often with Pasteurella multocida cohabitating the biofilm. A recently developed diagnostic test can detect antibodies to the EPS only in animals with systemic disease due to H. somni and is therefore capable of distinguishing between healthy animals colonized with H. somni and animals with systemic disease.
Topics: Animals; Biofilms; Cattle; Pasteurellaceae; Polysaccharides, Bacterial
PubMed: 26853691
DOI: 10.1007/82_2015_5013 -
Zentralblatt Fur Bakteriologie :... Jun 1993Selected strains representing established and newly described taxa in the family Pasteurellaceae were investigated for their cellular lipid and carbohydrate composition...
Selected strains representing established and newly described taxa in the family Pasteurellaceae were investigated for their cellular lipid and carbohydrate composition to clarify the taxonomic significance of such features. Methylated cellular fatty acids and acetylated derivatives of the cellular carbohydrates were determined by capillary gas chromatography using a flame ionization detector. In part the carbohydrates were identified by mass spectrometry. Phospholipids were determined by thin layer chromatography, the lipoquinones by high pressure liquid chromatography. The cellular fatty acid patterns proved to be uniform with minor variations, but the separation from the Neisseriaceae and from Moraxella was possible. Also the distribution of the phospholipids was uniform within the family. The lipoquinone contents were useful for the discrimination of groups within the family not necessarily reflecting the degree of genomic relatedness. The analysis of the cellular carbohydrates resulted in a common sugar pattern with all members of the family and characteristic carbohydrate profiles discriminating groups, often to the species level. All of the cytochemical features considered were useful for the characterization of the family Pasteurellaceae.
Topics: Actinobacillus; Carbohydrates; Fatty Acids; Haemophilus; Lipids; Pasteurella; Pasteurellaceae; Phospholipids; Quinones
PubMed: 8369580
DOI: 10.1016/s0934-8840(11)80496-2 -
Animal Health Research Reviews Dec 2009Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Mycoplasma bovis and Arcanobacterium pyogenes are all frequently implicated in bovine respiratory... (Review)
Review
Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Mycoplasma bovis and Arcanobacterium pyogenes are all frequently implicated in bovine respiratory disease (BRD). M. haemolytica is considered the most important of the group. These bacteria are commensals in the nasopharynx and establish infection in the lungs of cattle that are subjected to a variety of stresses. Factors that permit adherence to and proliferation in the lungs and factors that cause tissue destruction and inflammation have been identified as having major roles in pathogenesis. These virulence factors include protein adhesins, capsular polysaccharide, outer membrane proteins, iron-binding proteins, lipopolysacharide or lipooligosaccharide, enzymes and toxins. These bacterial products function to evade the immune system, damage the immune system and induce a severe inflammatory response.
Topics: Actinomycetales Infections; Animals; Arcanobacterium; Bovine Respiratory Disease Complex; Cattle; Mannheimia haemolytica; Mycoplasma Infections; Mycoplasma bovis; Pasteurella Infections; Pasteurella multocida; Pasteurellaceae; Pneumonia of Calves, Enzootic
PubMed: 20003651
DOI: 10.1017/S1466252309990193 -
Journal of Wildlife Diseases Jul 2013We used 16S rRNA sequencing and leukotoxin gene (lktA) screening via PCR assay to clarify phylogenetic and epidemiologic relationships among Pasteurellaceae isolated...
We used 16S rRNA sequencing and leukotoxin gene (lktA) screening via PCR assay to clarify phylogenetic and epidemiologic relationships among Pasteurellaceae isolated from bighorn sheep (Ovis canadensis). Only six of 21 bighorn isolates identified as "Mannheimia haemolytica" in original laboratory reports appeared to be isolates of M. haemolytica sensu stricto based on 16S rRNA sequence comparisons; the remainder grouped with M. glucosida (n=8) or M. ruminalis (n=7). Similarly, 16S rRNA sequence comparisons grouped only 16 of 25 trehalose-fermenting bighorn isolates with reference strains of Bibersteinia trehalosi; nine other trehalose-fermenting bighorn isolates formed a clade divergent from B. trehalosi reference strains and may belong to another species. Of the 16 bighorn isolates identified as B. trehalosi by 16S rRNA sequences, only nine carried detectable lktA and thus seemed likely pathogens; none of the Bibersteinia clade isolates yielded detectable lktA despite reportedly showing β hemolysis in culture. Our findings suggest that traditional metabolism-based methods for identifying Pasteurellaceae isolates lack sufficient accuracy and resolution for reliably discerning bacterial causes of respiratory disease in bighorn sheep. Consequently, these traditional methods should minimally be augmented by molecular techniques to improve epidemiologic relevance. Streamlined surveillance approaches focused primarily on detecting pathogenic Pasteurellaceae (e.g., M. haemolytica sensu stricto and lktA-positive B. trehalosi) and other select pathogens may be most informative for investigating and managing bighorn respiratory disease.
Topics: Animals; Colorado; Exotoxins; Female; Male; Pasteurellaceae; Pasteurellaceae Infections; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sheep; Sheep Diseases; Sheep, Bighorn
PubMed: 23778616
DOI: 10.7589/2012-11-274 -
Veterinary Research Communications Oct 2006The aim of the present study was to determine which Pasteurella and Mannheimia species are present in the upper respiratory tract of healthy calves with no history of...
The aim of the present study was to determine which Pasteurella and Mannheimia species are present in the upper respiratory tract of healthy calves with no history of antimicrobial treatment prior to sampling. The presence of subpopulations of tetracycline-resistant Pasteurellaceae was also investigated. Nasal swabs from 61 loose group-housed, clinically healthy calves, 1 to 4 months old, from 16 dairy herds were inoculated aerobically on a selective medium (Columbia agar with 5% ovine blood and 16 mg/L bacitracin) with or without 4 mg/L oxytetracycline (OTC). A total of 43 strains belonging to the family Pasteurellaceae were isolated from 38 calves (62.3%) out of 13 herds (81.3%). The predominant organisms were Pasteurella multocida subsp. multocida (57.4%), Mannheimia varigena (4.9%) and M. haemolytica (3.2%). Growth of Pasteurellaceae on the OTC-containing medium was seen only with samples from two herds (6 animals; 9.8%), and on only one farm this proved to be an OTC-resistant subpopulation. Minimum inhibitory concentration (MIC) determinations by means of agar dilution confirmed a low prevalence of OTC-resistant Pasteurellaceae, with overall MIC(50) and MIC(90) values of 0.25 and 32 mg/L, respectively. These data do not support the hypothesis that the relative high frequency of tetracycline-resistant P. multocida isolates from fatal cases of bovine respiratory disease is related to the presence of minor tetracycline-resistance subpopulations within this species.
Topics: Animals; Anti-Bacterial Agents; Cattle; Cattle Diseases; Colony Count, Microbial; Dose-Response Relationship, Drug; Mannheimia; Microbial Sensitivity Tests; Nasopharynx; Pasteurella; Pasteurellaceae; Pasteurellaceae Infections; Prevalence; Tetracycline Resistance
PubMed: 17004035
DOI: 10.1007/s11259-006-3347-8 -
Journal of Bacteriology Apr 2013Bacterial membranes serve as selective environmental barriers and contain determinants required for bacterial colonization and survival. Cell envelopes of Gram-negative...
Bacterial membranes serve as selective environmental barriers and contain determinants required for bacterial colonization and survival. Cell envelopes of Gram-negative bacteria consist of an outer and an inner membrane separated by a periplasmic space. Most Gram-negative bacteria display a smooth outer surface (e.g., Enterobacteriaceae), whereas members of the Pasteurellaceae and Moraxellaceae families show convoluted surfaces. Aggregatibacter actinomycetemcomitans, an oral pathogen representative of the Pasteurellaceae family, displays a convoluted membrane morphology. This phenotype is associated with the presence of morphogenesis protein C (MorC). Inactivation of the morC gene results in a smooth membrane appearance when visualized by two-dimensional (2D) electron microscopy. In this study, 3D electron microscopy and atomic force microscopy of whole-mount bacterial preparations as well as 3D electron microscopy of ultrathin sections of high-pressure frozen and freeze-substituted specimens were used to characterize the membranes of both wild-type and morC mutant strains of A. actinomycetemcomitans. Our results show that the mutant strain contains fewer convolutions than the wild-type bacterium, which exhibits a higher curvature of the outer membrane and a periplasmic space with 2-fold larger volume/area ratio than the mutant bacterium. The inner membrane of both strains has a smooth appearance and shows connections with the outer membrane, as revealed by visualization and segmentation of 3D tomograms. The present studies and the availability of genetically modified organisms with altered outer membrane morphology make A. actinomycetemcomitans a model organism for examining membrane remodeling and its implications in antibiotic resistance and virulence in the Pasteurellaceae and Moraxellaceae bacterial families.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Cell Membrane; Drug Resistance, Bacterial; Gene Expression Regulation, Bacterial; Microscopy, Atomic Force; Microscopy, Electron, Transmission; Moraxellaceae; Mutation; Pasteurellaceae; Surface Properties; Virulence
PubMed: 23378507
DOI: 10.1128/JB.02149-12 -
Zentralblatt Fur Bakteriologie :... Jun 1993Previously, virtually complete 16S ribosomal ribonucleic acid sequences were determined for 54 strains of species in the family Pasteurellaceae. The sequences for 16...
Previously, virtually complete 16S ribosomal ribonucleic acid sequences were determined for 54 strains of species in the family Pasteurellaceae. The sequences for 16 additional strains have been determined, bringing the total number of strains sequenced to 70. The additional strains include: Actinobacillus hominis, A. muris, A. salpingitis, Pasteurella bettyae, P. mairii, P. testudinis, and Bisgaard taxa 2, 3, 5, 6, 7, 8, 9, 13, and 14 (2 strains). A phylogenetic tree was constructed based upon sequence similarity using the Neighbor-Joining method. The additional sequence information and phylogenetic analysis generally supported our previously described phylogenetic structure for the family Pasteurellaceae. Cluster 1, containing Haemophilus sensu stricto, was unchanged. P. mairii was closely related to P. aerogenes and Bisgaard taxon 6 was related to H. somnus in Cluster 2. A. salpingitidis and Bisgaard taxa 2, 3, 7, and 13 fell in Cluster 3 which contains Pasteurella sensu stricto. A. hominis was closely related to Actinobacillus sensu stricto species in Cluster 4A. Bisgaard taxa 5, 8, 9 and P. bettyae fell in Cluster 4B. A. muris was related to P. pneumotropica in Cluster 5. Haemophilus parainfluenzae strains branched deeply as a 6th cluster. Bisgaard taxon 14 and P. testudinis formed a 7th cluster which branched deeper than any previously described clusters in the family Pasteurellaceae. The branching was extremely complex and taxonomic division of the family into phylogenetically and phenotypically coherent genera will be difficult.
Topics: Actinobacillus; Base Sequence; DNA Probes; Haemophilus; Molecular Sequence Data; Pasteurella; Pasteurellaceae; Phylogeny; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 7690271
DOI: 10.1016/s0934-8840(11)80489-5 -
BMC Evolutionary Biology Oct 2006Many bacteria can take up DNA, but the evolutionary history and function of natural competence and transformation remain obscure. The sporadic distribution of competence...
BACKGROUND
Many bacteria can take up DNA, but the evolutionary history and function of natural competence and transformation remain obscure. The sporadic distribution of competence suggests it is frequently lost and/or gained, but this has not been examined in an explicitly phylogenetic context. Additional insight may come from the sequence specificity of uptake by species such as Haemophilus influenzae, where a 9 bp uptake signal sequence (USS) repeat is both highly overrepresented in the genome and needed for efficient DNA uptake. We used the distribution of competence genes and DNA uptake specificity in H. influenzae's family, the Pasteurellaceae, to examine the ancestry of competence.
RESULTS
A phylogeny of the Pasteurellaceae based on 12 protein coding genes from species with sequenced genomes shows two strongly supported subclades: the Hin subclade (H. influenzae, Actinobacillus actinomycetemcomitans, Pasteurella multocida, Mannheimia succiniciproducens, and H. somnus), and the Apl subclade (A. pleuropneumoniae, M. haemolytica, and H. ducreyi). All species contained homologues of all known H. influenzae competence genes, consistent with an ancestral origin of competence. Competence gene defects were identified in three species (H. somnus, H. ducreyi and M. haemolytica); each appeared to be of recent origin. The assumption that USS arise by mutation rather than copying was first confirmed using alignments of H. influenzae proteins with distant homologues. Abundant USS-like repeats were found in all eight Pasteurellacean genomes; the repeat consensuses of species in the Hin subclade were identical to that of H. influenzae (AAGTGCGGT), whereas members of the Apl subclade shared the consensus ACAAGCGGT. All species' USSs had the strong consensus and flanking AT-rich repeats of H. influenzae USSs. DNA uptake and competition experiments demonstrated that the Apl-type repeat is a true USS distinct from the Hin-type USS: A. pleuropneumoniae preferentially takes up DNA fragments containing the Apl-type USS over both H. influenzae and unrelated DNAs, and H. influenzae prefers its own USS over the Apl type.
CONCLUSION
Competence and DNA uptake specificity are ancestral properties of the Pasteurellaceae, with divergent USSs and uptake specificity distinguishing only the two major subclades. The conservation of most competence genes over the approximately 350 million year history of the family suggests that lineages that lose competence may be evolutionary dead ends.
Topics: Amino Acid Sequence; Bacterial Proteins; Biological Evolution; DNA; Gene Expression Regulation, Bacterial; Molecular Sequence Data; Mutation; Pasteurellaceae; Transformation, Bacterial
PubMed: 17038178
DOI: 10.1186/1471-2148-6-82 -
Acta Pathologica, Microbiologica, Et... Aug 1986Incorrect diagnosis of species belonging to the family Pasteurellaceae Pohl 1981 is often due to inadequate laboratory identification techniques. Reinvestigations of 56...
Incorrect diagnosis of species belonging to the family Pasteurellaceae Pohl 1981 is often due to inadequate laboratory identification techniques. Reinvestigations of 56 human isolates of Pasteurellaceae and comparison of the results obtained with those obtained from nine reference strains in 65 different tests allowed classification of 26 strains as P. multocida ssp. multocida, 11 strains as P. multocida ssp. septica, 12 strains as P. canis, 4 strains as P. dagmatis and 1 strain as P. stomatitis. Two strains were tentatively classified with P. haemolytica biogroup 2(T) and the SP-group, respectively. The present investigation also showed that the type strains of P. gallinarum and Haemophilus aphrophilus were phenotypically related. Members of the family Pasteurellacea Pohl 1981 should be considered as potential etiologic agents of any local infection following animal bites or scratches.
Topics: Bites and Stings; Haemophilus; Humans; Pasteurella; Pasteurella Infections; Phenotype
PubMed: 3751576
DOI: 10.1111/j.1699-0463.1986.tb03044.x -
Microbiological Reviews Dec 1989The etiological agent of the sexually transmitted genital ulcer disease chancroid was first described in 1889 by Auguste Ducrey following repeated autoinoculation of... (Review)
Review
The etiological agent of the sexually transmitted genital ulcer disease chancroid was first described in 1889 by Auguste Ducrey following repeated autoinoculation of purulent ulcer material from a series of patients. The organism was isolated on artificial media a decade later but has remained difficult to isolate consistently, resulting in controversy over its characteristics and role as the causative agent of chancroid. Because of its fastidious growth requirements, including unknown components in blood, the organism was included in the original description of the genus Haemophilus. Requirement for exogenous hemin and limited phenotypic characteristics, including structural and antigenic properties, suggested that Haemophilus ducreyi was a valid member of the genus Haemophilus. Recent studies of respiratory quinones, deoxyribonucleic acid hybridization, and competition for homologous transformation of the type species, H. influenzae, suggest that H. ducreyi is unrelated to any of the present species of the family Pasteurellaceae, which includes members of the genera Haemophilus, Actinobacillus, and Pasteurella. This review summarizes the early studies with H. ducreyi and our current knowledge of the microbiology of this important human pathogen.
Topics: Chancroid; Haemophilus ducreyi; Humans; Microscopy, Electron
PubMed: 2687678
DOI: 10.1128/mr.53.4.377-389.1989