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1.
Infect Immun ; 78(8): 3475-83, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20515935

RESUMO

Many lipoproteins are expressed on the surfaces of mycoplasmas, and some have been implicated as playing roles in pathogenesis. Family 2 lipoproteins of Mycoplasma pneumoniae have a conserved "mycoplasma lipoprotein X" central domain and a "mycoplasma lipoprotein 10" C-terminal domain and are differentially expressed in response to environmental conditions. Homologues of family 2 lipoproteins are Mycoplasma specific and include the lipoprotein of Mycoplasma gallisepticum, encoded by the MGA0674 gene. Comparative transcriptomic analysis of the M. gallisepticum live attenuated vaccine strain F and the virulent strain R(low), reported in this study, indicated that MGA0674 is one of several differentially expressed genes. The MGA0674-encoded lipoprotein is a proteolytically processed, immunogenic, TX-114 detergent-phase protein which appears to have antigenic divergence between field strains R(low) and S6. We examined the virulence of an R(low) Delta MGA0674 mutant (P1H9) in vivo and observed reduced recovery and attenuated virulence in the tracheas of experimentally infected chickens. The virulence of two additional R(low) Delta MGA0674 mutants, 2162 and 2204, was assessed in a second in vivo virulence experiment. These mutants exhibited partial to complete attenuation in vivo, but recovery was observed more frequently. Since only Mycoplasma species harbor homologues of MGA0674, the gene product has been renamed "Mycoplasma-specific lipoprotein A" (MslA). Collectively, these data indicate that MslA is an immunogenic lipoprotein exhibiting reduced expression in an attenuated strain and plays a role in M. gallisepticum virulence.


Assuntos
Proteínas de Bactérias/fisiologia , Lipoproteínas/fisiologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/patogenicidade , Doenças das Aves Domésticas/microbiologia , Fatores de Virulência/fisiologia , Animais , Proteínas de Bactérias/genética , Galinhas , Feminino , Deleção de Genes , Perfilação da Expressão Gênica , Lipoproteínas/deficiência , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/patologia , Doenças das Aves Domésticas/patologia , Traqueia/microbiologia , Traqueia/patologia , Virulência , Fatores de Virulência/deficiência
2.
Microb Genom ; 6(1)2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30810518

RESUMO

Sequence type (ST)73 has emerged as one of the most frequently isolated extraintestinal pathogenic Escherichia coli. To examine the localized diversity of ST73 clonal groups, including their mobile genetic element profile, we sequenced the genomes of 16 multiple-drug resistant ST73 isolates from patients with urinary tract infection from a single hospital in Sydney, Australia, between 2009 and 2011. Genome sequences were used to generate a SNP-based phylogenetic tree to determine the relationship of these isolates in a global context with ST73 sequences (n=210) from public databases. There was no evidence of a dominant outbreak strain of ST73 in patients from this hospital, rather we identified at least eight separate groups, several of which reoccurred, over a 2 year period. The inferred phylogeny of all ST73 strains (n=226) including the ST73 clone D i2 reference genome shows high bootstrap support and clusters into four major groups that correlate with serotype. The Sydney ST73 strains carry a wide variety of virulence-associated genes, but the presence of iss, pic and several iron-acquisition operons was notable.


Assuntos
Escherichia coli/genética , Genoma Bacteriano , Austrália , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Hospitais , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único , Infecções Urinárias/microbiologia , Fatores de Virulência/genética
3.
Sci Rep ; 8(1): 17697, 2018 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-30523267

RESUMO

Enzootic pneumonia incurs major economic losses to pork production globally. The primary pathogen and causative agent, Mycoplasma hyopneumoniae, colonises ciliated epithelium and disrupts mucociliary function predisposing the upper respiratory tract to secondary pathogens. Alleviation of disease is reliant on antibiotics, vaccination, and sound animal husbandry, but none are effective at eliminating M. hyopneumoniae from large production systems. Sustainable pork production systems strive to lower reliance on antibiotics but lack of a detailed understanding of the pathobiology of M. hyopneumoniae has curtailed efforts to develop effective mitigation strategies. M. hyopneumoniae is considered an extracellular pathogen. Here we show that M. hyopneumoniae associates with integrin ß1 on the surface of epithelial cells via interactions with surface-bound fibronectin and initiates signalling events that stimulate pathogen uptake into clathrin-coated vesicles (CCVs) and caveosomes. These early events allow M. hyopneumoniae to exploit an intracellular lifestyle by commandeering the endosomal pathway. Specifically, we show: (i) using a modified gentamicin protection assay that approximately 8% of M. hyopneumoniae cells reside intracellularly; (ii) integrin ß1 expression specifically co-localises with the deposition of fibronectin precisely where M. hyopneumoniae cells assemble extracellularly; (iii) anti-integrin ß1 antibodies block entry of M. hyopneumoniae into porcine cells; and (iv) M. hyopneumoniae survives phagolysosomal fusion, and resides within recycling endosomes that are trafficked to the cell membrane. Our data creates a paradigm shift by challenging the long-held view that M. hyopneumoniae is a strict extracellular pathogen and calls for in vivo studies to determine if M. hyopneumoniae can traffic to extrapulmonary sites in commercially-reared pigs.


Assuntos
Células Epiteliais/microbiologia , Mycoplasma hyopneumoniae/patogenicidade , Pneumonia Suína Micoplasmática/microbiologia , Animais , Membrana Celular/metabolismo , Membrana Celular/microbiologia , Endossomos/metabolismo , Endossomos/microbiologia , Células Epiteliais/metabolismo , Fibronectinas/metabolismo , Integrina beta1/metabolismo , Pneumonia Suína Micoplasmática/metabolismo , Suínos
4.
Vet Microbiol ; 115(4): 329-38, 2006 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-16621346

RESUMO

Swine erysipelas vaccines are routinely used to protect pigs against peracute and acute/urticarial forms of Erysipelothrix. Between 1995 and 1998, 34 swine herds across four Australian states experienced vaccine failure. Forty-four isolates of Erysipelothrix rhusiopathiae of serovars 2, 1a, 1b and 1bx21 were recovered from 15 of these 34 vaccine breakdown herds. These isolates were characterised by restriction fragment length polymorphism (RFLP) analyses using RsaI and AluI on whole cell DNA and for the presence of plasmid DNA. Results were compared with those of 20 isolates from 16 herds unaffected by vaccine breakdown and 13 isolates representing 10 reference strains. The majority of breakdown herds possessed isolates of serovar 2 (9/15 herds), followed by serovar 1a (5 herds). No geographic predominance of a single serovar was evident. The identification of 10 RsaI profiles from whole cell DNA among the 44 isolates from 15 breakdown herds indicated that a single, new clonal lineage of E. rhusiopathiae was not responsible for vaccine failure. RsaI RFLP analyses detected a further 14 distinct profiles among 20 field strains unassociated with vaccine breakdowns, and none matched profiles of the 10 serovar reference strains for serovars 1a, 1b, 2 or 21. This technique is recommended for epidemiological studies of E. rhusiopathiae strains.


Assuntos
Vacinas Bacterianas/imunologia , Erysipelothrix/genética , Erysipelothrix/imunologia , Polimorfismo de Fragmento de Restrição , Erisipela Suína/microbiologia , Animais , Austrália/epidemiologia , DNA Bacteriano/análise , Erysipelothrix/classificação , Erysipelothrix/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase/veterinária , Suínos , Erisipela Suína/epidemiologia , Erisipela Suína/prevenção & controle
5.
Infect Genet Evol ; 32: 199-207, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25795385

RESUMO

In Australia, outbreaks of clinical theileriosis caused by Theileria orientalis have been largely associated with the Ikeda genotype which can occur as a sole infection, or more commonly, as a mixture of genotypes. The most prevalent genotype, Chitose, frequently co-occurs with type Ikeda, however the role of this genotype in clinical disease has not been clearly established. Furthermore, the dynamics of individual genotypes in field infection of cattle have not been examined. In this study we developed quantitative PCR (qPCR) and genotyping methods to examine the role of the Chitose genotype in clinical disease and to investigate the temporal dynamics of T. orientalis Ikeda, Chitose and Buffeli genotypes in naïve animals introduced to a T. orientalis-endemic area. Analysis of the major piroplasm surface protein (MPSP) genes of Chitose isolates revealed the presence of two distinct phylogenetic clusters, Chitose A and Chitose B. A genotyping assay aimed at determining Chitose A/B allele frequency revealed that the Chitose A phylogenetic cluster is strongly associated with clinical disease but nearly always co-occurs with the Ikeda genotype. qPCR revealed that the Chitose genotype (particularly Chitose A), undergoes temporal switching in conjunction with the Ikeda genotype and contributes substantially to the overall parasite burden. The benign Buffeli genotype can also undergo temporal switching but levels of this genotype appear to remain low relative to the Ikeda and Chitose types. Interplay between vector and host immunological factors is presumed to be critical to the population dynamics observed in this study. Genotypic switching likely contributes to the persistence of T. orientalis in the host.


Assuntos
Doenças dos Bovinos/parasitologia , Bovinos/parasitologia , Surtos de Doenças/veterinária , Genótipo , Theileria/genética , Theileriose/parasitologia , Animais , Austrália/epidemiologia , Doenças dos Bovinos/epidemiologia , DNA de Protozoário/genética , Técnicas de Genotipagem , Filogenia , Filogeografia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Theileria/isolamento & purificação , Theileriose/epidemiologia
6.
Biochem Pharmacol ; 35(20): 3511-6, 1986 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-3768038

RESUMO

N-hydroxyparacetamol treatment of rat kidney cells gave rise to a dose-dependent decrease in DNA synthesis. A concentration of 1.0 mM N-hydroxyparacetamol at pH 7.2 decreased the level of DNA synthesis to 13.0 +/- 2.3% of the control value after 1 hr incubation. This compound also caused a perturbation of cell cycle progression. A concentration of 0.44 mM N-hydroxyparacetamol induced G1/S and S phase blocks. These delays became evident at approximately 12 hr after treatment and persisted until about 15 hr when cells started to recover. It seems unlikely that N-hydroxyparacetamol inhibits DNA synthesis and perturbs cycle progression through alterations to DNA structure as such, since this compound failed to alter the migration pattern of naked plasmid DNA.


Assuntos
Acetaminofen/análogos & derivados , Ciclo Celular/efeitos dos fármacos , Acetaminofen/farmacologia , Animais , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Concentração de Íons de Hidrogênio , Rim/citologia , Conformação de Ácido Nucleico/efeitos dos fármacos , Ratos , Fatores de Tempo
7.
FEMS Microbiol Lett ; 198(1): 17-22, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11325548

RESUMO

The prevalence of complex Shiga toxin-producing Escherichia coli (STEC), i.e. STEC containing accessory virulence factors intimin (eaeA) and/or enterohaemorrhagic E. coli haemolysin (ehxA) and their serotypes were determined in diagnostic bovine faecal samples processed during a 3 months period. The presence of complex STEC was determined using PCR and vancomycin-cefixime-cefsulodin blood agar (BVCCA) using a dual approach which involved (i) direct culture of faecal samples on BVCCA followed by mutiplex PCR of BVCCA positive colonies and (ii) culture of faecal samples enriched in modified EC (mEC) broth (with a complex STEC profile determined by PCR) on BVCCA followed by multiplex PCR of BVCCA positive colonies. Using both techniques complex STEC were isolated from 23 (18.7%) of the 123 faecal samples. Complex STEC were isolated from 14 faecal samples by direct culture on BVCCA and 13 faecal samples yielded complex STEC by culture of mEC broths with a complex STEC profile on BVCCA. Only four samples were positive using both techniques. The serotypes isolated included O5:H-, O26:H-, O26:H11, O91:H21, O111:H-, O111:H8, O104:H11, O113:H21 and O157:H8. This study confirms that non-O157 STEC can be isolated from bovine faeces and that they carry types associated with human disease. This work also demonstrates that the use of a dual approach is advisable to increase the likelihood of isolating complex STEC.


Assuntos
Adesinas Bacterianas , Técnicas Bacteriológicas , Proteínas de Transporte , Doenças dos Bovinos/microbiologia , Diarreia/veterinária , Proteínas de Escherichia coli , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Toxina Shiga I/biossíntese , Toxina Shiga II/biossíntese , Animais , Proteínas da Membrana Bacteriana Externa/análise , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Bovinos , Cefixima , Cefsulodina , Meios de Cultura , Diarreia/microbiologia , Escherichia coli/classificação , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Proteínas Hemolisinas/análise , Proteínas Hemolisinas/genética , Reação em Cadeia da Polimerase , Sorotipagem , Toxina Shiga I/análise , Toxina Shiga I/genética , Toxina Shiga II/análise , Toxina Shiga II/genética , Vancomicina , Virulência
8.
FEMS Microbiol Lett ; 173(2): 311-8, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10227161

RESUMO

Melissococcus pluton, the causative agent of European foulbrood is an economically significant disease of honey bees (Apis mellifera) across most regions of the world and is prevalent throughout most states of Australia. 49 Isolates of M. pluton recovered from diseased colonies or honey samples in New South Wales, Queensland, South Australia, Tasmania and Victoria were compared using SDS-PAGE, Western immunoblotting and restriction endonuclease analyses. DNA profiles of all 49 geographically diverse isolates showed remarkably similar AluI profiles although four isolates (one each from Queensland, South Australia, New South Wales and Victoria) displayed minor profile variations compared to AluI patterns of all other isolates. DNA from a subset of the 49 Australian and three isolates from the United Kingdom were digested separately with the restriction endonucleases CfoI, RsaI and DraI. Restriction endonuclease fragment patterns generated using these enzymes were also similar although minor variations were noted. SDS-PAGE of whole cell proteins from 13 of the 49 isolates from different states of Australia, including the four isolates which displayed minor profile variations (AluI) produced indistinguishable patterns. Major immunoreactive proteins of approximate molecular masses of 21, 24, 28, 30, 36, 40, 44, 56, 60, 71, 79 and 95 kDa were observed in immunoblots of whole cell lysates of 22 of the 49 isolates and reacted with rabbit hyperimmune antibodies raised against M. pluton whole cells. Neither SDS-PAGE or immunoblotting was capable of distinguishing differences between geographically diverse isolates of M. pluton. Collectively these data confirm that Australian isolates of M. pluton are genetically homogeneous and that this species may be clonal. Plasmid DNA was not detected in whole cell DNA profiles of any isolate resolved using agarose gel electrophoresis.


Assuntos
Abelhas/microbiologia , Variação Genética , Cocos Gram-Positivos/genética , Animais , Austrália , Western Blotting , DNA Bacteriano/análise , Eletroforese em Gel de Poliacrilamida , Cocos Gram-Positivos/isolamento & purificação , Mapeamento por Restrição
9.
J Med Microbiol ; 47(8): 679-88, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9877188

RESUMO

Capsular types A and D of Pasteurella multocida cause economic losses in swine because of their association with progressive atrophic rhinitis (PAR) and enzootic pneumonia. There have been no studies comparing whole-cell DNA profiles of isolates associated with these two porcine respiratory diseases. Twenty-two isolates of P. multocida from diseased pigs in different geographic localities within Australia were characterised genotypically by restriction endonuclease analysis (REA) with the enzyme CfoI. Seven of 12 P. multocida isolates from nasal swabs from pigs in herds where PAR was either present or suspected displayed a capsular type D phenotype. These were shown to possess the toxA gene by polymerase chain reaction (PCR) and Southern hybridisation, and further substantiated by production of cytotoxin in vitro. The CfoI profile of one of these seven isolates, which was from the initial outbreak of PAR in Australia (in Western Australia, WA), was identical with profiles of all six other toxigenic isolates from sporadic episodes in New South Wales (NSW). The evidence suggests that the strain involved in the initial outbreak was responsible for the spread of PAR to the eastern states of Australia. Another 10 isolates, representing both capsular types A and D, were isolated exclusively from porcine lung lesions after sporadic outbreaks of enzootic pneumonia in NSW and WA. CfoI restriction endonuclease profiles of these isolates revealed considerable genomic heterogeneity. Furthermore, none of these possessed the toxA gene. This suggests that P. multocida strains with the toxA gene do not have a competitive survival advantage in the lower respiratory tract or that toxin production does not play a role in the pathology of pneumonic lesions, or both. REA with polyacrylamide gel electrophoresis and silver staining was found to be a practical and discriminatory tool for epidemiological tracing of P. multocida outbreaks associated with PAR or pneumonia in pigs.


Assuntos
Surtos de Doenças/veterinária , Infecções por Pasteurella/veterinária , Pasteurella multocida/classificação , Pneumonia Bacteriana/veterinária , Rinite Atrófica/veterinária , Doenças dos Suínos/microbiologia , Animais , Austrália/epidemiologia , Cápsulas Bacterianas/análise , Toxinas Bacterianas/biossíntese , Toxinas Bacterianas/genética , Southern Blotting , DNA Bacteriano/análise , Eletroforese em Gel de Poliacrilamida , Regulação Bacteriana da Expressão Gênica , Genótipo , Mucosa Nasal/microbiologia , Infecções por Pasteurella/epidemiologia , Infecções por Pasteurella/microbiologia , Pasteurella multocida/genética , Pasteurella multocida/patogenicidade , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/microbiologia , Reação em Cadeia da Polimerase , Mapeamento por Restrição/veterinária , Rinite Atrófica/epidemiologia , Rinite Atrófica/microbiologia , Coloração pela Prata , Suínos , Doenças dos Suínos/epidemiologia
10.
Vet Microbiol ; 39(3-4): 261-73, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8042274

RESUMO

An ELISA for the detection of serum antibodies to Mycoplasma hypopneumoniae in pigs and based on a 43 kDa purified protein derived from the cytoplasmic membrane of M. hyopneumoniae strain J is described. This ELISA (MHPP ELISA) was compared with another recently described (Auspharm ELISA, Sheldrake and Romalis 1992) that is based on column-purified sonicated proteins of strain J. Using sample to negative ELISA ratios of 3 and 4 as cutoffs for inconclusive and positive reactors respectively (compared to 2 and 3 for the Auspharm ELISA), the two tests had high specificity (MHPP 99.6%; Auspharm 100%) in 280 SPF pigs. In 176 pigs from commercial herds with endemic M. hyopneumoniae, the MHPP ELISA showed a higher sensitivity than the Auspharm ELISA in both high lung score (LS > or = 5) (85.5% vs. 69.9%) and low lung score (0 < LS < 5) (57.9% vs. 49%) pigs when the positive cutoff for each test was selected. The sensitivity when the inconclusive cutoff was selected was similar in both tests (85%; 85.7%) when low and high lung score pigs were pooled. Altough the MHPP also gave more positive reactors in 36 pigs from M. hyopneumoniae-infected herds with no lung pathology at slaughter than the Auspharm ELISA (11 vs. 4), the total number of inconclusive and positive reactors in these pigs was similar for both tests (18 vs. 14). The MHPP ELISA gave significantly higher ELISA ratios in infected pigs (up to 17.9) than the Auspharm ELISA (up to 9), and earlier seroconversion in naturally-infected (6-8 weeks vs. 9-10 weeks) and experimentally-infected pigs (2-4 weeks vs. 4-6 weeks post infection).


Assuntos
Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Mycoplasma/imunologia , Animais , Antígenos de Bactérias/análise , Antígenos de Bactérias/imunologia , Pulmão/patologia , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/veterinária , Pneumonia Suína Micoplasmática/diagnóstico , Pneumonia Suína Micoplasmática/veterinária , Organismos Livres de Patógenos Específicos , Suínos , Doenças dos Suínos/diagnóstico
11.
Vet Microbiol ; 79(1): 47-62, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11230928

RESUMO

The apxIVA gene, a recently discovered RTX determinant of Actinobacillus pleuropneumoniae, was shown to be species-specific. DNA hybridization experiments using probes for various regions of apxIVA revealed that the 3'-terminus of this gene was present in all 14 serotypes of A. pleuropneumoniae but absent from phylogenetically related species. A primer pair spanning this region specifically amplified a 422bp fragment in PCR experiments with DNA from the reference strains of the 14 serotypes and 194 field strains isolated from various geographic locations worldwide. DNA sequence analysis of PCR products derived from all serotypes were identical except in serotypes 3, 8, and 10, which showed minor differences. The PCR did not amplify any product when DNA from 17 different bacterial species closely related to A. pleuropneumoniae was used as template. In addition, the PCR was negative with DNA of several Actinobacillus sp. which were initially characterized as A. pleuropneumoniae using routine phenotypic and serological analyses but which were subsequently shown by 16S rRNA sequence analysis to belong to yet undefined Actinobacillus species. The sensitivity of the PCR was determined to be 10pg of A. pleuropneumoniae DNA. A set of nested primers amplified a 377bp fragment specifically with A. pleuropneumoniae DNA. DNA titration experiments using the flanking and nested primer pairs showed an improved level of sensitivity to approximately 10fg of genomic DNA. The nested PCR was used to monitor the spread of A. pleuropneumoniae in pigs experimentally infected with a virulent serotype 1 strain and housed in a controlled environment facility. A. pleuropneumoniae DNA could be detected by nested PCR in nasal swab samples of infected pigs receiving either a high dose (5x10(5)) or a low dose (1x10(4)) challenge and in unchallenged cohorts that were contact-infected by the inoculated animals. Furthermore, PCR confirmed the presence of A. pleuropneumoniae in 16/17 homogenates from necrotic lung lesions, while the bacterium was successfully recovered from 13 of these lesions by culture.


Assuntos
Infecções por Actinobacillus/veterinária , Actinobacillus pleuropneumoniae/isolamento & purificação , Proteínas de Bactérias/genética , Reação em Cadeia da Polimerase/veterinária , Doenças dos Suínos/diagnóstico , Infecções por Actinobacillus/diagnóstico , Actinobacillus pleuropneumoniae/genética , Animais , Southern Blotting/veterinária , DNA Bacteriano/análise , Hibridização In Situ/veterinária , Pulmão/microbiologia , Cavidade Nasal/microbiologia , Sensibilidade e Especificidade , Análise de Sequência de DNA/veterinária , Suínos , Doenças dos Suínos/microbiologia
12.
Aust Vet J ; 75(7): 504-11, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9258425

RESUMO

OBJECTIVE: To investigate the protective efficacy of a pool of denatured membrane protein antigens of Mycoplasma hyopneumoniae (J strain) in the molecular size range 70 to 85 kDa (F3 antigen) in combination with adjuvants for pigs challenged with M hyopneumoniae. DESIGN: A vaccine efficacy experiment with assessment of serum and respiratory tract antibody responses. PROCEDURE: F3 antigens were emulsified with five different adjuvants. To groups of three pigs per vaccine, four vaccines were given by intramuscular injection, and two vaccines, including one of those given intramuscularly, were given by intraperitoneal injection. RESULTS: Compared to six unvaccinated pigs, animals vaccinated with F3 antigen displayed significantly reduced pneumonia (54% reduction in mean lung score) following experimental challenge. Analysis of post-vaccination, pre-challenge IgG and IgA ELISA antibody absorbances in serum and respiratory tract washings revealed no correlation with lung score. Six weeks after challenge, pigs previously vaccinated intramuscularly mostly demonstrated greater IgG and IgA responses in respiratory tract washings, and greater IgG serum antibody responses, than those vaccinated by intraperitoneal injection. CONCLUSION: Pigs vaccinated with M hyponeumoniae antigens in the molecular size range of 70 to 85 kDa showed a significant reduction in lung lesions compared with unvaccinated control animals after experimental challenge. IgG and IgA antibody concentrations in serum and respiratory tract washings after vaccination do not provide a useful prognostic indicator of protection from enzootic pneumonia.


Assuntos
Anticorpos Antibacterianos/biossíntese , Vacinas Bacterianas/imunologia , Mycoplasma/imunologia , Pneumonia Suína Micoplasmática/veterinária , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/imunologia , Vacinas Bacterianas/administração & dosagem , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Imunoglobulina A/análise , Imunoglobulina A/biossíntese , Imunoglobulina A/sangue , Imunoglobulina G/análise , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Incidência , Injeções Intramusculares/métodos , Injeções Intramusculares/veterinária , Injeções Intraperitoneais/métodos , Injeções Intraperitoneais/veterinária , Proteínas de Membrana/administração & dosagem , Proteínas de Membrana/imunologia , Peso Molecular , Mucosa/química , Mucosa/imunologia , Mucosa/patologia , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Prognóstico , Sistema Respiratório/química , Sistema Respiratório/imunologia , Sistema Respiratório/patologia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/imunologia , Vacinação/métodos
15.
Int J Syst Evol Microbiol ; 59(Pt 6): 1353-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19502315

RESUMO

The Mycoplasma mycoides cluster consists of six pathogenic mycoplasmas causing disease in ruminants, which share many genotypic and phenotypic traits. The M. mycoides cluster comprises five recognized taxa: Mycoplasma mycoides subsp. mycoides Small Colony (MmmSC), M. mycoides subsp. mycoides Large Colony (MmmLC), M. mycoides subsp. capri (Mmc), Mycoplasma capricolum subsp. capricolum (Mcc) and M. capricolum subsp. capripneumoniae (Mccp). The group of strains known as Mycoplasma sp. bovine group 7 of Leach (MBG7) has remained unassigned, due to conflicting data obtained by different classification methods. In the present paper, all available data, including recent phylogenetic analyses, have been reviewed, resulting in a proposal for an emended taxonomy of this cluster: (i) the MBG7 strains, although related phylogenetically to M. capricolum, hold sufficient characteristic traits to be assigned as a separate species, i.e. Mycoplasma leachii sp. nov. (type strain, PG50(T) = N29(T) = NCTC 10133(T) = DSM 21131(T)); (ii) MmmLC and Mmc, which can only be distinguished by serological methods and are related more distantly to MmmSC, should be combined into a single subspecies, i.e. Mycoplasma mycoides subsp. capri, leaving M. mycoides subsp. mycoides (MmmSC) as the exclusive designation for the agent of contagious bovine pleuropneumonia. A taxonomic description of M. leachii sp. nov. and emended descriptions of M. mycoides subsp. mycoides and M. mycoides subsp. capri are presented. As a result of these emendments, the M. mycoides cluster will hereafter be composed of five taxa comprising three subclusters, which correspond to the M. mycoides subspecies, the M. capricolum subspecies and the novel species M. leachii.


Assuntos
Artrite Infecciosa/veterinária , Doenças dos Bovinos/microbiologia , Doenças das Cabras/microbiologia , Mycoplasma mycoides/classificação , Mycoplasma/classificação , Pleuropneumonia Contagiosa/microbiologia , Animais , Artrite Infecciosa/microbiologia , Austrália , Bovinos , Genótipo , Cabras , Mycoplasma/genética , Mycoplasma/patogenicidade , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma mycoides/genética , Mycoplasma mycoides/patogenicidade , Filogenia , Sorotipagem , Especificidade da Espécie , Turquia
16.
J Clin Microbiol ; 31(11): 2927-32, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8263177

RESUMO

We compared random amplified polymorphic DNA (RAPD) fingerprinting with cross-absorption agglutination and restriction enzyme analysis for typing bovine leptospires. Using RAPD fingerprinting, we examined a number of Leptospira serovars, namely, hardjo genotypes bovis and prajitno, pomona, balcanica, tarassovi, swajizak, kremastos, australis, and zanoni, which are likely to be isolated from Australian cattle. Each serovar and genotype had a unique RAPD profile. Of 26 field isolates of Leptospira, 23 were identified as hardjo genotype bovis subtype A, 2 were identified as zanoni, and 1 was identified as pomona by RAPD fingerprinting, and their types were confirmed by cross-absorption agglutination and restriction enzyme analysis.


Assuntos
Bovinos/microbiologia , Impressões Digitais de DNA , DNA Bacteriano/análise , Leptospira/isolamento & purificação , Animais , Amplificação de Genes , Leptospira/genética , Reação em Cadeia da Polimerase
17.
J Bacteriol ; 169(1): 53-60, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3025187

RESUMO

Several transposon Tn5-induced mutants of the broad-host-range Rhizobium sp. strain NGR234 produce little or no detectable acidic exopolysaccharide (EPS) and are unable to induce nitrogen-fixing nodules on Leucaena leucocephala var. Peru or siratro plants. The ability of these Exo- mutants to induce functioning nodules on Leucaena plants was restored by coinoculation with a Sym plasmid-cured (Nod- Exo+) derivative of parent strain NGR234, purified EPS from the parent strain, or the oligosaccharide from the EPS. Coinoculation with EPS or related oligosaccharide also resulted in formation of nitrogen-fixing nodules on siratro plants. In addition, an Exo- mutant (ANU437) of Rhizobium trifolii ANU794 was able to form nitrogen-fixing nodules on white clover in the presence of added EPS or related oligosaccharide from R. trifolii ANU843. These results demonstrate that the absence of Rhizobium EPSs can result in failure of effective symbiosis with both temperate and subtropical legumes.


Assuntos
Mutação , Fixação de Nitrogênio , Polissacarídeos/biossíntese , Rhizobium/genética , Configuração de Carboidratos , Elementos de DNA Transponíveis , Plasmídeos
18.
Infect Immun ; 65(6): 2502-7, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9169801

RESUMO

Mycoplasma hyopneumoniae is the etiological agent of porcine enzootic pneumonia, a commercially expensive respiratory disease of swine. Salmonella typhimurium SL3261 was used as a live carrier of plasmid pKF1, which encodes a 15-kDa recombinant M. hyopneumoniae protein. This expressed recombinant protein consists of the carboxy-terminal 11 kDa of a 42-kDa M. hyopneumoniae NrdF ribonucleotide reductase R2 subunit protein. Rabbit anti-15-kDa serum was able to inhibit the growth of viable M. hyopneumoniae J in vitro. When used as a live oral vaccine, S. typhimurium SL3261(pKF1) induced a significant secretory immunoglobulin A immune response in the lungs of mice orally immunized against the M. hyopneumoniae antigen. Utilization of live oral vaccines expressing potentially protective M. hyopneumoniae proteins, such as the NrdF antigen, which can stimulate a lung mucosal response against surface-accessible proteins may provide a cost-effective alternative to the present control strategies used for porcine enzootic pneumonia.


Assuntos
Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Mycoplasma/imunologia , Salmonella typhimurium/genética , Vacinas Sintéticas/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Vacinas Atenuadas/imunologia
19.
Appl Environ Microbiol ; 66(3): 1098-106, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10698777

RESUMO

Twenty-five unique CfoI-generated whole-cell DNA profiles were identified in a study of 30 Paenibacillus alvei isolates cultured from honey and diseased larvae collected from honeybee (Apis mellifera) colonies in geographically diverse areas in Australia. The fingerprint patterns were highly variable and readily discernible from one another, which highlighted the potential of this method for tracing the movement of isolates in epidemiological studies. 16S rRNA gene fragments (length, 1,416 bp) for all 30 isolates were enzymatically amplified by PCR and subjected to restriction analysis with DraI, HinfI, CfoI, AluI, FokI, and RsaI. With each enzyme the restriction profiles of the 16S rRNA genes from all 30 isolates were identical (one restriction fragment length polymorphism [RFLP] was observed in the HinfI profile of the 16S rRNA gene from isolate 17), which confirmed that the isolates belonged to the same species. The restriction profiles generated by using DraI, FokI, and HinfI differentiated P. alvei from the phylogenetically closely related species Paenibacillus macerans and Paenibacillus macquariensis. Alveolysin gene fragments (length, 1, 555 bp) were enzymatically amplified from some of the P. alvei isolates (19 of 30 isolates), and RFLP were detected by using the enzymes CfoI, Sau3AI, and RsaI. Extrachromosomal DNA ranging in size from 1 to 10 kb was detected in 17 of 30 (57%) P. alvei whole-cell DNA profiles. Extensive biochemical heterogeneity was observed among the 28 P. alvei isolates examined with the API 50CHB system. All of these isolates were catalase, oxidase, and Voges-Proskauer positive and nitrate negative, and all produced acid when glycerol, esculin, and maltose were added. The isolates produced variable results for 16 of the 49 biochemical tests; negative reactions were recorded in the remaining 30 assays. The genetic and biochemical heterogeneity in P. alvei isolates may be a reflection of adaptation to the special habitats in which they originated.


Assuntos
Bacillus/classificação , Abelhas/microbiologia , Animais , Bacillus/genética , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , DNA Ribossômico/genética , Genes Bacterianos , Proteínas Hemolisinas/genética , Compostos Orgânicos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética
20.
Appl Environ Microbiol ; 65(2): 868-72, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9925634

RESUMO

A multiplex PCR was developed for the rapid detection of genes encoding Shiga toxins 1 and 2 (stx1 and stx2), intimin (eaeA), and enterohemolysin A (hlyA) in 444 fecal samples derived from healthy and clinically affected cattle, sheep, pigs, and goats. The method involved non-solvent-based extraction of nucleic acid from an aliquot of an overnight culture of feces in EC (modified) broth. The detection limit of the assay for both fecal samples and pure cultures was between 18 and 37 genome equivalents. stx1 and hlyA were the most commonly encountered virulence factors.


Assuntos
Adesinas Bacterianas , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Proteínas de Transporte , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli , Escherichia coli/genética , Fezes/microbiologia , Proteínas Hemolisinas/genética , Reação em Cadeia da Polimerase/métodos , Animais , Animais Domésticos/microbiologia , Bovinos , DNA Bacteriano/análise , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Toxinas Shiga , Virulência
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