Systematic analysis of diguanylate cyclases that promote biofilm formation by Pseudomonas fluorescens Pf0-1.
J Bacteriol
; 193(18): 4685-98, 2011 Sep.
Article
em En
| MEDLINE
| ID: mdl-21764921
ABSTRACT
Cyclic di-GMP (c-di-GMP) is a broadly conserved, intracellular second-messenger molecule that regulates biofilm formation by many bacteria. The synthesis of c-di-GMP is catalyzed by diguanylate cyclases (DGCs) containing the GGDEF domain, while its degradation is achieved through the phosphodiesterase activities of EAL and HD-GYP domains. c-di-GMP controls biofilm formation by Pseudomonas fluorescens Pf0-1 by promoting the cell surface localization of a large adhesive protein, LapA. LapA localization is regulated posttranslationally by a c-di-GMP effector system consisting of LapD and LapG, which senses cytoplasmic c-di-GMP and modifies the LapA protein in the outer membrane. Despite the apparent requirement for c-di-GMP for biofilm formation by P. fluorescens Pf0-1, no DGCs from this strain have been characterized to date. In this study, we undertook a systematic mutagenesis of 30 predicted DGCs and found that mutations in just 4 cause reductions in biofilm formation by P. fluorescens Pf0-1 under the conditions tested. These DGCs were characterized genetically and biochemically to corroborate the hypothesis that they function to produce c-di-GMP in vivo. The effects of DGC gene mutations on phenotypes associated with biofilm formation were analyzed. One DGC preferentially affects LapA localization, another DGC mainly controls swimming motility, while a third DGC affects both LapA and motility. Our data support the conclusion that different c-di-GMP-regulated outputs can be specifically controlled by distinct DGCs.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Pseudomonas fluorescens
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Biofilmes
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Fósforo-Oxigênio Liases
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Proteínas de Escherichia coli
Idioma:
En
Revista:
J Bacteriol
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Estados Unidos