Regulation of flagellar motor switching by c-di-GMP phosphodiesterases in Pseudomonas aeruginosa.
J Biol Chem
; 294(37): 13789-13799, 2019 09 13.
Article
em En
| MEDLINE
| ID: mdl-31350333
ABSTRACT
The second messenger cyclic diguanylate (c-di-GMP) plays a prominent role in regulating flagellum-dependent motility in the single-flagellated pathogenic bacterium Pseudomonas aeruginosa The c-di-GMP-mediated signaling pathways and mechanisms that control flagellar output remain to be fully unveiled. Studying surface-tethered and free-swimming P. aeruginosa PAO1 cells, we found that the overexpression of an exogenous diguanylate cyclase (DGC) raises the global cellular c-di-GMP concentration and thereby inhibits flagellar motor switching and decreases motor speed, reducing swimming speed and reversal frequency, respectively. We noted that the inhibiting effect of c-di-GMP on flagellar motor switching, but not motor speed, is exerted through the c-di-GMP-binding adaptor protein MapZ and associated chemotactic pathways. Among the 22 putative c-di-GMP phosphodiesterases, we found that three of them (DipA, NbdA, and RbdA) can significantly inhibit flagellar motor switching and swimming directional reversal in a MapZ-dependent manner. These results disclose a network of c-di-GMP-signaling proteins that regulate chemotactic responses and flagellar motor switching in P. aeruginosa and establish MapZ as a key signaling hub that integrates inputs from different c-di-GMP-signaling pathways to control flagellar output and bacterial motility. We rationalized these experimental findings by invoking a model that postulates the regulation of flagellar motor switching by subcellular c-di-GMP pools.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
GMP Cíclico
/
Flagelos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Singapura