Toxin-antitoxin vapBC locus participates in formation of the dormant state in Mycobacterium smegmatis.
FEMS Microbiol Lett
; 352(1): 69-77, 2014 Mar.
Article
em En
| MEDLINE
| ID: mdl-24417293
ABSTRACT
Toxin-antitoxin (TA) loci are widely spread in bacterial plasmids and chromosomes. Toxins affect important functions of bacterial cells such as translation, replication and cell-wall synthesis, whereas antitoxins are toxin inhibitors. Participation in formation of the dormant state in bacteria is suggested to be a possible function of toxins. Here we show that overexpression of VapC toxin in Mycobacterium smegmatis results in development of morphologically distinct ovoid cells. The ovoid cells were nonreplicating and revealed a low level of uracil incorporation and respiration that indicated their dormant status. To validate the role of VapBC in dormancy formation, we used a model of dormant, 'nonculturable' (NC) M. smegmatis cells obtained in potassium-limited conditions. Overexpression of VapB antitoxin prevented transition to dormancy, presumably due to a decreased level of the free VapC protein. Indeed, this effect of the VapB was neutralized by coexpression of the cognate VapC as a part of the vapBC operon. In summary, these findings reveal participation of vapBC products in formation of the dormant state in M. smegmatis.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Toxinas Bacterianas
/
Glicoproteínas de Membrana
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Mycobacterium smegmatis
/
Proteínas de Ligação a DNA
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
FEMS Microbiol Lett
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Federação Russa