Deletion of the LuxR-type regulator VjbR in Brucella canis affects expression of type IV secretion system and bacterial virulence, and the mutant strain confers protection against Brucella canis challenge in mice.
Microb Pathog
; 139: 103865, 2020 Feb.
Article
em En
| MEDLINE
| ID: mdl-31715318
ABSTRACT
Brucella spp. are facultative intracellular pathogens and zoonotic agents which pose a huge threat to human health and animal husbandry. The B. melitensis, B. abortus, and B. suis cause undulant fever and influenza-like symptoms in humans. However, the effects of B. canis have not been extensively studied. The quorum sensing-dependent transcriptional regulator VjbR influences the Brucella virulence in smooth type Brucella strains, such as B. melitensis, B. abortus and rough type Brucella ovis. However, the function of VjbR in the rough-type B. canis is unknown. In the present study, we discovered that deletion of this regulator significantly affected Brucella virulence in macrophage and mice infection models. The expression levels of virB operon and the ftcR gene were significantly altered in the vjbR mutant strain. We further investigated the protective effect of different doses of the vjbR mutant in mice and the results indicated that VjbR conferred protection against the virulent B. canis strain. This study presents the first evidence that the transcriptional regulator VjbR has important function in B. canis. In addition, according to its reduced virulence and the protective immunity it induces in mice, it can be a potential live attenuated vaccine against B. canis.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Proteínas Repressoras
/
Proteínas de Bactérias
/
Brucelose
/
Regulação Bacteriana da Expressão Gênica
/
Transativadores
/
Brucella canis
/
Sistemas de Secreção Tipo IV
/
Mutação
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Microb Pathog
Assunto da revista:
DOENCAS TRANSMISSIVEIS
/
MICROBIOLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China