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1.
Braz J Microbiol ; 51(3): 1327-1332, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31650466

RESUMO

Clostridium chauvoei is the etiological agent of blackleg, an infectious disease affecting cattle and small ruminants worldwide. This disease can manifest as classical blackleg, a condition in which skeletal muscles are affected and visceral blackleg, which affects the heart, sublingual muscles, and the diaphragm. The pathogenesis of the visceral form of the disease is poorly understood. The objective of this study is to determine and analyze complete genomic sequences of six C. chauvoei strains, five isolates from skeletal muscle and one isolate from a visceral case of blackleg in Brazil, to provide insights into the differences in pathogenic profiles of strains causing the different forms of disease. The full genomes of the six C. chauvoei strains were sequenced and comparative analyses were performed among these genomes and the C. chauvoei reference strain JF4335. The results of this study revealed that the genomes of the C. chauvoei strains analyzed are highly conserved; no particular differences were noted that could be associated with the two different clinical manifestations of the disease.


Assuntos
Doenças dos Bovinos/microbiologia , Infecções por Clostridium/veterinária , Clostridium chauvoei/genética , Vísceras/microbiologia , Animais , Brasil , Bovinos , Infecções por Clostridium/microbiologia , Clostridium chauvoei/classificação , Clostridium chauvoei/isolamento & purificação , Genoma Bacteriano , Genômica , Humanos , Músculo Esquelético/microbiologia
2.
Infect Genet Evol ; 54: 287-298, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28720440

RESUMO

Clostridium (C.) chauvoei is a Gram-positive, spore forming, anaerobic bacterium. It causes black leg in ruminants, a typically fatal histotoxic myonecrosis. High quality circular genome sequences were generated for the C. chauvoei type strain DSM 7528T (ATCC 10092T) and a field strain 12S0467 isolated in Germany. The origin of replication (oriC) was comparable to that of Bacillus subtilis in structure with two regions containing DnaA boxes. Similar prophages were identified in the genomes of both C. chauvoei strains which also harbored hemolysin and bacterial spore formation genes. A CRISPR type I-B system with limited variations in the repeat number was identified. Sporulation and germination process related genes were homologous to that of the Clostridia cluster I group but novel variations for regulatory genes were identified indicative for strain specific control of regulatory events. Phylogenomics showed a higher relatedness to C. septicum than to other so far sequenced genomes of species belonging to the genus Clostridium. Comparative genome analysis of three C. chauvoei circular genome sequences revealed the presence of few inversions and translocations in locally collinear blocks (LCBs). The species genome also shows a large number of genes involved in proteolysis, genes for glycosyl hydrolases and metal iron transportation genes which are presumably involved in virulence and survival in the host. Three conserved flagellar genes (fliC) were identified in each of the circular genomes. In conclusion this is the first comparative analysis of circular genomes for the species C. chauvoei, enabling insights into genome composition and virulence factor variation.


Assuntos
Clostridium chauvoei/genética , Genoma Bacteriano , Genômica , Bacteriófagos , Composição de Bases , Infecções por Clostridium/microbiologia , Clostridium chauvoei/classificação , Clostridium chauvoei/virologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Biologia Computacional/métodos , Farmacorresistência Bacteriana , Genômica/métodos , Anotação de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Origem de Replicação , Análise de Sequência de DNA , Fatores de Virulência
3.
J Microbiol Methods ; 84(2): 307-11, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21182874

RESUMO

In the present study, a Taqman allelic discrimination assay based on three SNPs of the TPI gene is described. It was used as a differential diagnostic tool to detect blackleg and malignant edema. Sudden deaths of grazing ruminants, such as cattle, sheep and goats, which show clinical signs related to hyperacute infective processes, encouraged the development of a rapid and precise diagnostic molecular method. Specific primers and probes for Clostridium septicum and Clostridium chauvoei were designed on the basis of the TPI gene sequence. The multiplex PCR was tested on the DNA of a total of 57 strains, including 24 Clostridium chauvoei, 20 Clostridium septicum, 1 Bacillus anthracis and 12 other Clostridium spp. The DNA samples from Clostridium chauvoei and Clostridium septicum strains were amplified. Amplification of other DNA samples was not observed, with the exception of Clostridium tertium, which showed a weak positive signal. To avoid misdiagnosis, a confirmatory assay based on a Sybr green real time PCR was proposed. The authors confirmed the efficacy and the specificity of the test used in this study, which proved to be a useful tool for the diagnosis of clostridiosis that are often diagnosed using only traditional tools.


Assuntos
Técnicas Bacteriológicas/métodos , Infecções por Clostridium/veterinária , Clostridium chauvoei/isolamento & purificação , Clostridium septicum/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Triose-Fosfato Isomerase/genética , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Infecções por Clostridium/diagnóstico , Clostridium chauvoei/classificação , Clostridium chauvoei/genética , Clostridium septicum/classificação , Clostridium septicum/genética , Primers do DNA/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Doenças das Cabras/diagnóstico , Doenças das Cabras/microbiologia , Cabras , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia
4.
J Clin Microbiol ; 48(4): 1093-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20129968

RESUMO

A real-time PCR assay based on the 16S rRNA gene sequence was designed for differentiation of blackleg-causing Clostridium chauvoei and Clostridium septicum, a phylogenetically closely related bacterium responsible for malignant edema. In order to exclude false-negative results, an internal amplification control was included in the assay. A set of three probes, one specific for C. chauvoei, one specific for C. septicum, and one specific for both species, permitted unequivocal detection of C. chauvoei in tests of 32 Clostridium sp. strains and 10 non-Clostridium strains. The assay proved to be sensitive, detecting one genome of C. chauvoei or C. septicum per PCR and 1.79 x 10(3) C. chauvoei cells/g artificially contaminated muscle tissue. In tests of 11 clinical specimens, the real-time PCR assay yielded the same results as an established conventional PCR method.


Assuntos
Infecções por Clostridium/diagnóstico , Clostridium chauvoei/classificação , Clostridium chauvoei/isolamento & purificação , Clostridium septicum/classificação , Clostridium septicum/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Infecções por Clostridium/microbiologia , Primers do DNA/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Humanos , Reação em Cadeia da Polimerase/normas , RNA Ribossômico 16S/genética , Padrões de Referência , Sensibilidade e Especificidade
5.
Anaerobe ; 14(3): 190-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18407530

RESUMO

Clostridium chauvoei is the etiologic agent of blackleg, a high mortality rate disease affecting mainly cattle and sheep. Carcasses of animals affected by the disease are the chief source of soil infection and considered as an ever-present threat to livestock health. A study was undertaken to examine the cross-contamination of C. chauvoei in two different bovine slaughterhouses using restriction endonuclease analysis (REA) and protein analysis. Samples from various sites of two different bovine slaughterhouses were screened and 34 isolates were identified by conventional techniques and 16S rRNA gene (rrs) sequencing. C. chauvoei were isolated from carcass, soil, and sewage from slaughterhouses examined. The isolates were differentiated using REA and whole-cell and excretory protein pattern analysis combined with numerical analysis and cluster formation. The alpha and beta toxins produced by the strains were characterized. Our preliminary results suggest that REA combined with numerical analysis provides additional criteria and characteristic banding patterns for the study of the cross-contamination and characterization of C. chauvoei. The effects of temperature, oxygen tension, and enzymes on C. chauvoei hemolysin activity were also discussed. These microorganisms may be a potential contaminant of carcasses and widespread in soil of abattoir environments. The information of area-specific distribution of C. chauvoei strains and its toxin characteristics may give an efficient program in protecting cattle and other ruminants.


Assuntos
Matadouros , Bovinos/microbiologia , Infecções por Clostridium/veterinária , Clostridium chauvoei , Esgotos/microbiologia , Microbiologia do Solo , Animais , Doenças dos Bovinos/microbiologia , Infecções por Clostridium/microbiologia , Clostridium chauvoei/classificação , Clostridium chauvoei/genética , Clostridium chauvoei/isolamento & purificação , Enzimas de Restrição do DNA/metabolismo , Eletroforese em Gel de Poliacrilamida , Proteínas Hemolisinas/metabolismo , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
J Clin Microbiol ; 46(4): 1545-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18256217

RESUMO

The first human case of fulminant gas gangrene caused by Clostridium chauvoei, a pathogen causing ruminant blackleg, was confirmed for a 58-year-old man suffering from diabetes mellitus. The patient developed conspicuous emphysematous gangrene in the right chest wall as well as intravascular gas entrapments and died 2 h after hospital arrival.


Assuntos
Infecções por Clostridium/complicações , Clostridium chauvoei/classificação , Clostridium chauvoei/isolamento & purificação , Gangrena Gasosa/microbiologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/patologia , Clostridium chauvoei/genética , DNA Espaçador Ribossômico/análise , Complicações do Diabetes , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética
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