Binding interface between the Salmonella σ(S)/RpoS subunit of RNA polymerase and Crl: hints from bacterial species lacking crl.
Sci Rep
; 5: 13564, 2015 Sep 04.
Article
en En
| MEDLINE
| ID: mdl-26338235
ABSTRACT
In many Gram-negative bacteria, including Salmonella enterica serovar Typhimurium (S. Typhimurium), the sigma factor RpoS/σ(S) accumulates during stationary phase of growth, and associates with the core RNA polymerase enzyme (E) to promote transcription initiation of genes involved in general stress resistance and starvation survival. Whereas σ factors are usually inactivated upon interaction with anti-σ proteins, σ(S) binding to the Crl protein increases σ(S) activity by favouring its association to E. Taking advantage of evolution of the σ(S) sequence in bacterial species that do not contain a crl gene, like Pseudomonas aeruginosa, we identified and assigned a critical arginine residue in σ(S) to the S. Typhimurium σ(S)-Crl binding interface. We solved the solution structure of S. Typhimurium Crl by NMR and used it for NMR binding assays with σ(S) and to generate in silico models of the σ(S)-Crl complex constrained by mutational analysis. The σ(S)-Crl models suggest that the identified arginine in σ(S) interacts with an aspartate of Crl that is required for σ(S) binding and is located inside a cavity enclosed by flexible loops, which also contribute to the interface. This study provides the basis for further structural investigation of the σ(S)-Crl complex.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
3_ND
Problema de salud:
3_neglected_diseases
/
3_zoonosis
Asunto principal:
Pseudomonas aeruginosa
/
Salmonella
/
Factor sigma
/
Proteínas Bacterianas
/
ARN Polimerasas Dirigidas por ADN
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Sci Rep
Año:
2015
Tipo del documento:
Article
País de afiliación:
Francia