BadR (BB0693) controls growth phase-dependent induction of rpoS and bosR in Borrelia burgdorferi via recognizing TAAAATAT motifs.
Mol Microbiol
; 98(6): 1147-67, 2015 Dec.
Article
en En
| MEDLINE
| ID: mdl-26331438
ABSTRACT
In Borrelia burgdorferi (Bb), the alternative sigma factor RpoS plays a central role during Bb's adaptation to ticks and mammals. Previous studies have demonstrated that RpoS is not expressed during the early stages of spirochetal growth or when Bb resides in ticks during the intermolt phase, but the molecular details of these events remain unknown. In the current study, biomagnetic bead separation of rpoS promoter-binding proteins, coupled with genetic inactivation, was employed to identify BadR (BB0693) as a negative regulator that controls growth phase-dependent induction of rpoS and bosR in Bb. When badR was inactivated, the expression of rpoS and bosR was induced only during the early stages of bacterial growth, but not during the stationary growth phase. Recombinant BadR bound to the promoter DNA of rpoS and the regulatory region upstream of bosR via AT-rich TAAAATAT motifs. Mutations in this motif markedly inhibited or abolished rBadR binding. These results suggest that BadR directly influences the expression of both rpoS and bosR in Bb. This newly recognized role for BadR to fine-tune the activation of the RpoN-RpoS pathway at strategic times in Bb's life cycle potentially represents another layer of gene control over σ(54)-dependent gene regulation.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Factor sigma
/
Proteínas Bacterianas
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Borrelia burgdorferi
/
Motivos de Nucleótidos
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Mol Microbiol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Año:
2015
Tipo del documento:
Article
País de afiliación:
Estados Unidos