Dataset Information

Regulation of Vibrio polysaccharide synthesis and virulence factor production by CdgC, a GGDEF-EAL domain protein, in Vibrio cholerae.

ABSTRACT: In Vibrio cholerae, the second messenger 3',5'-cyclic diguanylic acid (c-di-GMP) regulates several cellular processes, such as formation of corrugated colony morphology, biofilm formation, motility, and virulence factor production. Both synthesis and degradation of c-di-GMP in the cell are modulated by proteins containing GGDEF and/or EAL domains, which function as a diguanylate cyclase and a phosphodiesterase, respectively. The expression of two genes, cdgC and mbaA, which encode proteins harboring both GGDEF and EAL domains is higher in the rugose phase variant of V. cholerae than in the smooth variant. In this study, we carried out gene expression analysis to determine the genes regulated by CdgC in the rugose and smooth phase variants of V. cholerae. We determined that CdgC regulates expression of genes required for V. cholerae polysaccharide synthesis and of the transcriptional regulator genes vpsR, vpsT, and hapR. CdgC also regulates expression of genes involved in extracellular protein secretion, flagellar biosynthesis, and virulence factor production. We then compared the genes regulated by CdgC and by MbaA, during both exponential and stationary phases of growth, to elucidate processes regulated by them. Identification of the regulons of CdgC and MbaA revealed that the regulons overlap, but the timing of regulation exerted by CdgC and MbaA is different, suggesting the interplay and complexity of the c-di-GMP signal transduction pathways operating in V. cholerae.

SUBMITTER: Lim B

PROVIDER: S-EPMC1797307 | biostudies-literature | 2007 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Regulation of Vibrio polysaccharide synthesis and virulence factor production by CdgC, a GGDEF-EAL domain protein, in Vibrio cholerae.

Lim Bentley B Beyhan Sinem S Yildiz Fitnat H FH

Journal of bacteriology 20061122 3

In Vibrio cholerae, the second messenger 3',5'-cyclic diguanylic acid (c-di-GMP) regulates several cellular processes, such as formation of corrugated colony morphology, biofilm formation, motility, and virulence factor production. Both synthesis and degradation of c-di-GMP in the cell are modulated by proteins containing GGDEF and/or EAL domains, which function as a diguanylate cyclase and a phosphodiesterase, respectively. The expression of two genes, cdgC and mbaA, which encode proteins harbo ...[more]

PMID: 17122338

Similar Datasets

Project description:Vibrio parahaemolyticus rapidly colonizes surfaces using swarming motility. Surface contact induces the surface-sensing regulon, including lateral flagellar genes, spurring dramatic shifts in physiology and behavior. The bacterium can also adopt a sessile, surface-associated lifestyle and form robust biofilms. These alternate colonization strategies are influenced reciprocally by the second messenger c-di-GMP. Although V. parahaemolyticus possesses 43 predicted proteins with the c-di-GMP-forming GGDEF domain, none have been previously been identified as contributors to surface colonization. We sought to explore this knowledge gap by using a suppressor transposon screen to restore the swarming motility of a nonswarming, high-c-di-GMP strain. Two diguanylate cyclases, ScrJ and ScrL, each containing tetratricopeptide repeat-coupled GGDEF domains, were demonstrated to contribute additively to swarming gene repression. Both proteins required an intact catalytic motif to regulate. Another suppressor mapped in lafV, the last gene in a lateral flagellar operon. Containing a degenerate phosphodiesterase (EAL) domain, LafV repressed transcription of multiple genes in the surface sensing regulon; its repressive activity required LafK, the primary swarming regulator. Mutation of the signature EAL motif had little effect on LafV's repressive activity, suggesting that LafV belongs to the subclass of EAL-type proteins that are regulatory but not enzymatic. Consistent with these activities and their predicted effects on c-di-GMP, scrJ and scrL but not lafV, mutants affected the transcription of the c-di-GMP-responsive biofilm reporter cpsA::lacZ Our results expand the knowledge of the V. parahaemolyticus GGDEF/EAL repertoire and its roles in this surface colonization regulatory network.IMPORTANCE A key survival decision, in the environment or the host, is whether to emigrate or aggregate. In bacteria, c-di-GMP signaling almost universally influences solutions to this dilemma. In V. parahaemolyticus, c-di-GMP reciprocally regulates swarming and sticking (i.e., biofilm formation) programs of surface colonization. Key c-di-GMP-degrading phosphodiesterases responsive to quorum and nutritional signals have been previously identified. c-di-GMP binding transcription factors programming biofilm development have been studied. Here, we further develop the blueprint of the c-di-GMP network by identifying new participants involved in dictating the complex decision of whether to swarm or stay. These include diguanylate cyclases with tetratricopeptide domains and a degenerate EAL protein that, analogously to the negative flagellar regulator RflP/YdiV of enteric bacteria, serves to regulate swarming.

Project description:BACKGROUND:The cyclic-di-GMP (c-di-GMP) second messenger exemplifies a signaling system that regulates many bacterial behaviors of key importance; among them, c-di-GMP controls the transition between motile and sessile life-styles in bacteria. Cellular c-di-GMP levels in bacteria are regulated by the opposite enzymatic activities of diguanylate cyclases and phosphodiesterases, which are proteins that have GGDEF and EAL domains, respectively. Azospirillum is a genus of plant-growth-promoting bacteria, and members of this genus have beneficial effects in many agronomically and ecologically essential plants. These bacteria also inhabit aquatic ecosystems, and have been isolated from humus-reducing habitats. Bioinformatic and structural approaches were used to identify genes predicted to encode GG[D/E]EF, EAL and GG[D/E]EF-EAL domain proteins from nine genome sequences. RESULTS:The analyzed sequences revealed that the genomes of A. humicireducens SgZ-5T, A. lipoferum 4B, Azospirillum sp. B510, A. thiophilum BV-ST, A. halopraeferens DSM3675, A. oryzae A2P, and A. brasilense Sp7, Sp245 and Az39 encode for 29 to 41 of these predicted proteins. Notably, only 15 proteins were conserved in all nine genomes: eight GGDEF, three EAL and four GGDEF-EAL hybrid domain proteins, all of which corresponded to core genes in the genomes. The predicted proteins exhibited variable lengths, architectures and sensor domains. In addition, the predicted cellular localizations showed that some of the proteins to contain transmembrane domains, suggesting that these proteins are anchored to the membrane. Therefore, as reported in other soil bacteria, the Azospirillum genomes encode a large number of proteins that are likely involved in c-di-GMP metabolism. In addition, the data obtained here strongly suggest host specificity and environment specific adaptation. CONCLUSIONS:Bacteria of the Azospirillum genus cope with diverse environmental conditions to survive in soil and aquatic habitats and, in certain cases, to colonize and benefit their host plant. Gaining information on the structures of proteins involved in c-di-GMP metabolism in Azospirillum appears to be an important step in determining the c-di-GMP signaling pathways, involved in the transition of a motile cell towards a biofilm life-style, as an example of microbial genome plasticity under diverse in situ environments.

Dataset Information

Regulation of Vibrio polysaccharide synthesis and virulence factor production by CdgC, a GGDEF-EAL domain protein, in Vibrio cholerae.

Publications

Regulation of Vibrio polysaccharide synthesis and virulence factor production by CdgC, a GGDEF-EAL domain protein, in Vibrio cholerae.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets