RESUMO
Two-component signal transduction systems (TCS) are important elements in the interaction of endobacteria with host cells. They are basically composed of two proteins, an environmental signal sensor and a response regulator, which activate genes involved in a wide range of bacterial responses to their environment. We analyzed three sets of genes corresponding to TCS of Ehrlichia canis, a common tick-borne canine pathogen and the etiologic agent of canine monocytic ehrlichiosis, in order to identify the characteristic domains of the sensor and response regulator components. Analysis of sequence alignments of the corresponding proteins indicated a high degree of similarity to other members of the Anaplasmataceae TCS proteins, demonstrating that they could be useful as universal targets for development of new drugs against these bacteria. We also evaluated by quantitative PCR inhibition of E. canis by (2H)-1,4-benzoxazin-3(4H)-one (BOA), the core compound of the plant phenolic compound DIMBOA, which shows inhibitory action against TCS of the phytopathogen Agrobacterium tumefasciens. This bacterium exerts its pathogenicity by transferring oncogenic DNA (T-DNA) into plant cells; this transfer is mediated through a type-IV secretion system, which is regulated by the VirA/VirG TCS. The process of infection and pathogenesis of E. canis is associated with the secretion of effector proteins into the host cell cytoplasm through a T4SS system, which blocks the cell defense response. We suggest that BOA, and possibly other plant phenolic compounds that are TCS inhibitors, can be exploited in the search for new antiehrlichial drugs to be used alone or as complements in the treatment of canine monocytic ehrlichiosis.
Assuntos
Produtos Biológicos/farmacologia , Biologia Computacional/métodos , Ehrlichia canis/efeitos dos fármacos , Ehrlichia canis/genética , Plantas/química , Transdução de Sinais/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Benzoxazinas/farmacologia , Ehrlichia canis/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacosRESUMO
E. canis infection of the canine cell line DH82 is a routine in studies with this bacteria. A protocol for isolation of host cell free bacteria was developed based on the use of glass beads. Improvement of infection with E. canis isolated by this method was detected by real-time PCR.
Assuntos
Separação Celular/instrumentação , Separação Celular/métodos , Ehrlichia canis/isolamento & purificação , Corantes Fluorescentes/metabolismo , Compostos Orgânicos/metabolismo , Reação em Cadeia da Polimerase/métodos , Animais , Benzotiazóis , Linhagem Celular , DNA Bacteriano/análise , Diaminas , Doenças do Cão/microbiologia , Cães , Ehrlichia canis/genética , Ehrlichiose/microbiologia , Vidro , Humanos , QuinolinasRESUMO
E. canis infection of the canine cell line DH82 is a routine in studies with this bacteria. A protocol for isolation of host cell free bacteria was developed based on the use of glass beads. Improvement of infection with E. canis isolated by this method was detected by real-time PCR.
Assuntos
Humanos , Animais , Cães , DNA Bacteriano/análise , Ehrlichia canis/genética , Ehrlichia canis/isolamento & purificação , Doenças do Cão/microbiologia , Separação Celular/instrumentação , Separação Celular/métodos , Linhagem Celular , Corantes Fluorescentes/metabolismo , Compostos Orgânicos/metabolismo , Ehrlichiose/microbiologia , Vidro , Reação em Cadeia da Polimerase/métodosRESUMO
The partial DNA sequences of the 18S rRNA gene of Babesia canis and the 16S rRNA gene of Ehrlichia canis detected in dogs from Ribeirão Preto, Brazil, were compared to sequences from other strains deposited in GenBank. The E. canis strain circulating in Ribeirão Preto is identical to other strains previously detected in the region, whereas the subspecies Babesia canis vogeli is the main Babesia strain circulating in dogs from Ribeirão Preto.
As sequências parciais dos genes RNAr 18S de Babesia canis e RNAr 16S e Ehrlichiacanis detectados em cães de Ribeirão Preto, Brasil, foram comparadas à sequências de outras linhagens depositadas no GeneBank. A linhagem de E. canis circulando em Ribeirão Preto é idêntica a outras detectadas previamente na região, enquanto a sub-espécie B. canis vogeli é a principal linhagem de Babesia circulando em cães de Ribeirão Preto.
Assuntos
Animais , Cães , Babesiose , Sequência de Bases , Babesia/genética , Ehrlichiose , Ehrlichia canis/genética , Técnicas In Vitro , Reação em Cadeia da Polimerase , RNA , Carrapatos , Métodos , Técnicas e Procedimentos DiagnósticosAssuntos
Anaplasma/genética , Anaplasmose/microbiologia , Doenças do Cão/microbiologia , Trombocitopenia/veterinária , Anaplasma/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Brasil , Chaperoninas/genética , Primers do DNA , Bases de Dados de Ácidos Nucleicos , Doenças do Cão/sangue , Cães , Reação em Cadeia da Polimerase/veterinária , Alinhamento de Sequência/veterinária , Análise de Sequência/veterinária , Trombocitopenia/microbiologiaRESUMO
The partial DNA sequences of the 18S rRNA gene of Babesia canis and the 16S rRNA gene of Ehrlichia canis detected in dogs from Ribeirão Preto, Brazil, were compared to sequences from other strains deposited in GenBank. The E. canis strain circulating in Ribeirão Preto is identical to other strains previously detected in the region, whereas the subspecies Babesia canis vogeli is the main Babesia strain circulating in dogs from Ribeirão Preto.
RESUMO
Comparison of the partial DNA sequence of the 16S rRNA gene of Anaplasma platys detected in dogs from Ribeirão Preto, Brazil, to sequences of other strains previously deposited in GenBank showed that there are at least three A. platys strains circulating in South America.
A comparação de sequências parciais do gene 16S RNAr de Anaplasma platys detectadas em cães de Ribeirão Preto, Brasil, com sequências de outras linhagens previamente depositadas no GenBank indicam que existem pelo menos três linhagens de A. platys circulando na América do Sul.
