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Experimental Animals 2011Pasteurella pneumotropica is an opportunistic pathogen in rodents. Natural infection in immunodeficient animals suggests that immunodeficiency is a major factor in P....
Pasteurella pneumotropica is an opportunistic pathogen in rodents. Natural infection in immunodeficient animals suggests that immunodeficiency is a major factor in P. pneumotropica pathogenesis. To understand this process, we performed clinical, pathological and bacteriological studies of immunodeficient NOD/ShiJic-scid/Jcl and immunocompetent Crlj:CD1 (ICR) mice experimentally infected with P. pneumotropica ATCC 35149. From 14 days postinoculation, some of P. pneumotropica-infected NOD/ShiJic-scid/Jcl mice developed clinical signs of weight loss. Three of 10 P. pneumotropica-infected NOD/ShiJic-scid/Jcl mice developed clinical signs of depression, ruffled coat, and weight loss and died at 27, 34, and 59 days postinoculation. At 35 days postinoculation, almost all P. pneumotropica-infected NOD/ShiJic-scid/Jcl mice had lung abscesses. The bacteria were isolated from the upper and lower respiratory tracts, including the lungs, and blood. In contrast, P. pneumotropica-infected ICR mice exhibited no clinical signs or lesions. The bacteria were isolated from the upper, but not the lower respiratory tracts. We developed an animal model for understanding host interactions with P. pneumotropica.
Topics: Animals; Disease Models, Animal; Host-Pathogen Interactions; Immunocompetence; Immunocompromised Host; Mice; Mice, Inbred ICR; Mice, Inbred NOD; Mice, SCID; Pasteurella Infections; Pasteurella pneumotropica; Respiratory System; Virulence
PubMed: 22041283
DOI: 10.1538/expanim.60.463 -
PloS One 2015[Pasteurella] pneumotropica biotypes Jawetz and Heyl and [Actinobacillus] muris are the most prevalent Pasteurellaceae species isolated from laboratory mouse. However,...
[Pasteurella] pneumotropica biotypes Jawetz and Heyl and [Actinobacillus] muris are the most prevalent Pasteurellaceae species isolated from laboratory mouse. However, mechanisms contributing to their high prevalence such as the ability to form biofilms have not been studied yet. In the present investigation we analyze if these bacterial species can produce biofilms in vitro and investigate whether proteins, extracellular DNA and polysaccharides are involved in the biofilm formation and structure by inhibition and dispersal assays using proteinase K, DNase I and sodium periodate. Finally, the capacity of the biofilms to confer resistance to antibiotics is examined. We demonstrate that both [P.] pneumotropica biotypes but not [A.] muris are able to form robust biofilms in vitro, a phenotype which is widely spread among the field isolates. The biofilm inhibition and dispersal assays by proteinase and DNase lead to a strong inhibition in biofilm formation when added at the initiation of the biofilm formation and dispersed pre-formed [P.] pneumotropica biofilms, revealing thus that proteins and extracellular DNA are essential in biofilm formation and structure. Sodium periodate inhibited the bacterial growth when added at the beginning of the biofilm formation assay, making difficult the assessment of the role of β-1,6-linked polysaccharides in the biofilm formation, and had a biofilm stimulating effect when added on pre-established mature biofilms of [P.] pneumotropica biotype Heyl and a majority of [P.] pneumotropica biotype Jawetz strains, suggesting that the presence of β-1,6-linked polysaccharides on the bacterial surface might attenuate the biofilm production. Conversely, no effect or a decrease in the biofilm quantity was observed by biofilm dispersal using sodium periodate on further biotype Jawetz isolates, suggesting that polysaccharides might be incorporated in the biofilm structure. We additionally show that [P.] pneumotropica cells enclosed in biofilms were less sensitive to treatment with amoxicillin and enrofloxacin than planktonic bacteria. Taken together, these findings provide a first step in understanding of the biofilm mechanisms in [P.] pneumotropica, which might contribute to elucidation of colonization and pathogenesis mechanisms for these obligate inhabitants of the mouse mucosa.
Topics: Animals; Anti-Bacterial Agents; Biofilms; Deoxyribonuclease I; Endopeptidase K; Mice; Microbial Sensitivity Tests; Microscopy, Confocal; Pasteurella pneumotropica; Periodic Acid
PubMed: 26430880
DOI: 10.1371/journal.pone.0138778 -
Veterinary World Dec 2020Knowledge of potentially pathogenic bacteria presents in the oral cavity of dogs and cats may be helpful in determining appropriate treatment for infected bite wounds....
BACKGROUND AND AIM
Knowledge of potentially pathogenic bacteria presents in the oral cavity of dogs and cats may be helpful in determining appropriate treatment for infected bite wounds. About 120.000 people are exposed to dog and cat bites every year in Algeria, but little is known about the dog and cat oral flora causing bite wound complications. The purpose of this study was to identify potential zoonotic bacteria from oral cavity of dogs and cats and to determine their susceptibility to antibiotics to contribute to the treatment of bite wound infection.
MATERIALS AND METHODS
Oral swabs from 100 stray dogs and 100 stray cats were collected and cultured in several media: Chocolate agar, MacConkey agar, and Mannitol Salt Agar. Bacterial isolates were identified using several commercial kits of the analytical profile index and tested for antibiotic susceptibility by disk diffusion method.
RESULTS
Overall, 185/200 (92.5%) dogs and cats carried zoonotic bacteria in their mouths, of which 55.13% (102/185) had at least two bacterial pathogens. 374 pathogenic strains belonging to 15 genera were isolated: Eleven were Gram-negative (, , , , , , , and ) and four were Gram-positive (, , and , ). Fifty-one strains of were isolated from 44 carriers of (21 , 21 , and 9 spp.). strains were tested for antibiotic resistance. Resistance to at least one drug was observed in 8 (15.68%) of isolates and two strains (3.92%) were found to be multidrug-resistant (to two or more drugs). Erythromycin, penicillin, and ampicillin were the antimicrobials to which the isolates showed greater resistance (7.84%, 5.88%, and 3.92%, respectively).
CONCLUSION
To the best of our knowledge, this study is the first in Algeria to detect potential human pathogenic bacteria in the oral cavity of dogs and cats. It reveals that these animals have multiple zoonotic bacteria in their mouths including species, which may be multidrug-resistant.
PubMed: 33488002
DOI: 10.14202/vetworld.2020.2806-2814 -
Journal of Bacteriology Jan 1969Pneumonia caused by Mycoplasma pulmonis and Pasteurella pneumotropica was studied in conventional, specific pathogen-free (SPF), and germ-free mice. When P....
Pneumonia caused by Mycoplasma pulmonis and Pasteurella pneumotropica was studied in conventional, specific pathogen-free (SPF), and germ-free mice. When P. pneumotropica was serially passed in conventional mice, M. pulmonis, as well as P. pneumotropica, was recovered from mice with gross lesions. When M. pulmonis was serially passed in conventional mice, both organisms were recovered. SPF mice given a nasal instillation of M. pulmonis alone, P. pneumotropica alone, or a combination of the two developed pneumonia when both organisms were present. These findings suggested that both organisms contribute to typical murine pneumonia. That M. pulmonis might be an L form of P. pneumotropica was suggested because some SPF mice inoculated with either organism yielded both on culture. This possibility was investigated with mole per cent guanine plus cytosine (GC) content and nucleic acid hybridization techniques. The GC content of P. pneumotropica is 42.2 mole per cent and that of M. pulmonis is 28.6 mole per cent. No specific hybrids between deoxyribonucleic acid (DNA) from M. pulmonis and DNA from P. pneumotropica were detected. This and the wide disparity in GC content showed that M. pulmonis is not an L form of P. pneumotropica. In germ-free mice, intranasal instillation with either organism alone produced pneumonia. The lesions produced when each organism was inoculated independently were characterized by areas of consolidation with perivascular and peribronchial lymphocytic infiltration. Qualitatively, the lesions produced when both organisms were inoculated simultaneously more closely resembled those seen in naturally occurring murine pneumonia. Statistical analysis indicated that the quantitative effect of the two organisms was additive. The indirect fluorescent antibody technique was used to locate organisms in lung tissue sections. M. pulmonis localized in the bronchial epithelium and P. pneumotropica localized in the alveolar lesions.
Topics: Animals; Cytosine; DNA; Fluorescent Antibody Technique; Germ-Free Life; Guanine; Hot Temperature; L Forms; Lung; Mice; Mycoplasma Infections; Pasteurella Infections; Pneumonia
PubMed: 4884818
DOI: 10.1128/jb.97.1.337-349.1969 -
PloS One 2014Pasteurella pneumotropica is an opportunist Gram negative bacterium responsible for rodent pasteurellosis that affects upper respiratory, reproductive and digestive...
Pasteurella pneumotropica is an opportunist Gram negative bacterium responsible for rodent pasteurellosis that affects upper respiratory, reproductive and digestive tracts of mammals. In animal care facilities the presence of P. pneumotropica causes severe to lethal infection in immunodeficient mice, being also a potential source for human contamination. Indeed, occupational exposure is one of the main causes of human infection by P. pneumotropica. The clinical presentation of the disease includes subcutaneous abscesses, respiratory tract colonization and systemic infections. Given the ability of P. pneumotropica to fully disseminate in the organism, it is quite relevant to study the role of the complement system to control the infection as well as the possible evasion mechanisms involved in bacterial survival. Here, we show for the first time that P. pneumotropica is able to survive the bactericidal activity of the human complement system. We observed that host regulatory complement C4BP and Factor H bind to the surface of P. pneumotropica, controlling the activation pathways regulating the formation and maintenance of C3-convertases. These results show that P. pneumotropica has evolved mechanisms to evade the human complement system that may increase the efficiency by which this pathogen is able to gain access to and colonize inner tissues where it may cause severe infections.
Topics: Complement C3-C5 Convertases; Complement C4b-Binding Protein; Complement Factor H; Humans; Pasteurella pneumotropica
PubMed: 25347183
DOI: 10.1371/journal.pone.0111194 -
BMC Microbiology Mar 2011Pasteurella pneumotropica is a ubiquitous bacterium that is frequently isolated from laboratory rodents and causes various clinical symptoms in immunodeficient animals....
BACKGROUND
Pasteurella pneumotropica is a ubiquitous bacterium that is frequently isolated from laboratory rodents and causes various clinical symptoms in immunodeficient animals. Currently two RTX toxins, PnxIA and PnxIIA, which are similar to hemolysin-like high-molecular-weight exoproteins are known in this species. In this study, we identified and analyzed a further RTX toxin named PnxIIIA and the corresponding type I secretion system.
RESULTS
The RTX exoprotein, PnxIIIA, contains only a few copies of the RTX repeat-like sequence and 3 large repeat sequences that are partially similar to the outer membrane protein found in several prokaryotes. Recombinant PnxIIIA protein (rPnxIIIA) was cytotoxic toward J774A.1 mouse macrophage cells, whereas cytotoxicity was attenuated by the addition of anti-CD11a monoclonal antibody. rPnxIIIA could bind to extracellular matrices (ECMs) and cause hemagglutination of sheep erythrocytes. Binding was dependent on the 3 large repeat sequences in PnxIIIA. Protein interaction analyses indicated that PnxIIIA is mainly localized in the outer membrane of P. pneumotropica ATCC 35149 in a self-assembled oligomeric form. PnxIIIA is less cytotoxic to J774A.1 cells than PnxIA and PnxIIA.
CONCLUSIONS
The results implicate that PnxIIIA is located on the cell surface and participates in adhesion to ECMs and enhanced hemagglutination in the rodent pathogen P. pneumotropica.
Topics: Animals; Bacterial Outer Membrane Proteins; Bacterial Toxins; Cell Line; DNA, Bacterial; Erythrocytes; Hemagglutination; Macrophages; Mice; Molecular Sequence Data; Pasteurella pneumotropica; Protein Transport; Recombinant Proteins; Sequence Alignment; Sequence Analysis, DNA; Sheep; Virulence
PubMed: 21410992
DOI: 10.1186/1471-2180-11-55 -
Comparative Medicine Dec 2010Diagnosis of Pasteurella pneumotropica in laboratory animals relies on isolation of the organism, biochemical characterization, and, more recently, DNA-based diagnostic...
Diagnosis of Pasteurella pneumotropica in laboratory animals relies on isolation of the organism, biochemical characterization, and, more recently, DNA-based diagnostic methods. 16S rRNA and rpoB gene sequences were examined for development of a real-time PCR assay. Partial sequencing of rpoB (456 bp) and 16S rRNA (1368 bp) of Pasteurella pneumotropica isolates identified by microbiologic and biochemical assays indicated that either gene sequence can be used to distinguish P. pneumotropica from other members of the Pasteurellaceae family. However, alignment of rpoB sequences from the Pasteurella pneumotropica Heyl (15 sequences) and Jawetz (16 sequences) biotypes with other Pasteurellaceae sequences from GenBank indicated that although rpoB DNA sequencing could be used for diagnosis, development of diagnostic primers and probes would be difficult, because the sequence variability between Heyl and Jawetz biotypes is not clustered in any particular region of the rpoB sequence. In contrast, alignment of 16S rRNA sequences revealed a region with unique and stable nucleotide motifs sufficient to permit development of a specific fluorogenic real-time PCR assay to confirm P. pneumotropica isolated by culture and to differentiate Heyl and Jawetz biotypes.
Topics: Animals; Bacterial Proteins; Classification; DNA Primers; Mice; Pasteurella Infections; Pasteurella pneumotropica; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Rats; Rodent Diseases; Sequence Alignment; Sequence Analysis, DNA
PubMed: 21262128
DOI: No ID Found -
Experimental Animals Jan 2008To investigate the pathogenicities of P. pneumotropica (Pp) and V-factor dependent Pasteurellaceae (VFDP) in immunodeficient rats, experimental infections of F344-rnu...
To investigate the pathogenicities of P. pneumotropica (Pp) and V-factor dependent Pasteurellaceae (VFDP) in immunodeficient rats, experimental infections of F344-rnu rats were performed using 3 strains (ATCC 35149, CNP 160 and RPZ) of Pp and 4 strains (V6, V7, V8 and V9) of VFDP. Four animals per experimental group were inoculated twice on day 0 and post-inoculation day (PID) 14 with bacterial suspension intranasally. Two animals from each group were sacrificed on PID 60 and 120, and examined. In the animals inoculated with strains of Pp, sneezing was observed in some animals inoculated with strains ATCC 35149 and CNP 160 until PID 31. No clinical signs were observed in other animals. The strains were mainly isolated from the nasal cavity and trachea on PID 60, and the nasal cavity, trachea and lung on PID 120. Inflammation and necrosis of nasal cavity mucosa were observed in all animals inoculated with strains ATCC 35149 and CNP 160 in a histopathologic examination. No histopathological changes were observed in any other animal. In the animals inoculated with strains of VFDP, neither clinical disorder nor histopathological change was observed. The strains were mainly isolated from the trachea on PID 60, and from the trachea and lungs on PID 120. From these results, the pathogenicity of Pp in immunodeficient rats appears to differ by strain, and VFDP appears to be non-pathogenic in immunodeficient rats.
Topics: Animals; Female; Immunologic Deficiency Syndromes; Pasteurella pneumotropica; Pasteurellaceae; Pasteurellaceae Infections; Rats; Rats, Inbred F344; Rats, Mutant Strains; Rodent Diseases
PubMed: 18256519
DOI: 10.1538/expanim.57.57 -
Nucleic Acids Research Dec 2020CRISPR-Cas defense systems opened up the field of genome editing due to the ease with which effector Cas nucleases can be programmed with guide RNAs to access desirable...
CRISPR-Cas defense systems opened up the field of genome editing due to the ease with which effector Cas nucleases can be programmed with guide RNAs to access desirable genomic sites. Type II-A SpCas9 from Streptococcus pyogenes was the first Cas9 nuclease used for genome editing and it remains the most popular enzyme of its class. Nevertheless, SpCas9 has some drawbacks including a relatively large size and restriction to targets flanked by an 'NGG' PAM sequence. The more compact Type II-C Cas9 orthologs can help to overcome the size limitation of SpCas9. Yet, only a few Type II-C nucleases were fully characterized to date. Here, we characterized two Cas9 II-C orthologs, DfCas9 from Defluviimonas sp.20V17 and PpCas9 from Pasteurella pneumotropica. Both DfCas9 and PpCas9 cleave DNA in vitro and have novel PAM requirements. Unlike DfCas9, the PpCas9 nuclease is active in human cells. This small nuclease requires an 'NNNNRTT' PAM orthogonal to that of SpCas9 and thus potentially can broaden the range of Cas9 applications in biomedicine and biotechnology.
Topics: Amino Acid Sequence; Base Sequence; CRISPR-Associated Protein 9; CRISPR-Cas Systems; Cloning, Molecular; Clustered Regularly Interspaced Short Palindromic Repeats; Escherichia coli; Gene Editing; Gene Expression; Genetic Vectors; Genome, Bacterial; HEK293 Cells; Humans; Nucleic Acid Conformation; Pasteurella pneumotropica; RNA, Guide, CRISPR-Cas Systems; Recombinant Proteins; Rhodobacteraceae; Sequence Alignment; Sequence Homology, Amino Acid
PubMed: 33152077
DOI: 10.1093/nar/gkaa998 -
Laboratory Animals Apr 2021An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis,...
An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis, bacterial otitis media/interna (, , , and ), encephalitis, an abscess, neoplasia, a congenital malformation and an accidental or iatrogenic head trauma. Magnetic resonance imaging (MRI) revealed a large space-occupying right olfactory lobe intra-axial lesion with severe secondary left-sided subfalcine herniation. Following imaging, the animal was euthanized due to poor prognosis. Histopathologic examination revealed a unilateral, full-thickness bone defect at the base of the cribriform plate and nasal conchae dysplasia, resulting in the herniation of the olfactory bulb into the nasal cavity. There was also a left midline-shift of the frontal cortex and moderate catarrhal sinusitis in the left mandibular sinus. The MRI and histopathologic changes are consistent with a congenital malformation of the nasal cavity and frontal aspect of the skull known as an ethmoidal meningoencephalocele. Encephaloceles are rare abnormalities caused by herniation of contents of the brain through a defect in the skull which occur due to disruption of the neural tube closure at the level anterior neuropore or secondary to trauma, surgical complications, cleft palate or increased intracranial pressure. The etiology is incompletely understood but hypotheses include genetics, vitamin deficiency, teratogens, infectious agents and environmental factors. Ethmoidal encephaloceles have been reported in multiple species including humans but have not been reported previously in mice. There are multiple models for spontaneous and induced craniofacial malformation in mice, but none described for ethmoidal encephaloceles.
Topics: Animals; Diagnosis, Differential; Encephalocele; Ethmoid Bone; Fatal Outcome; Female; Magnetic Resonance Imaging; Meningocele; Mice; Mice, Inbred C57BL
PubMed: 32787540
DOI: 10.1177/0023677220944449