Dataset Information

Contribution of the cold shock protein CspA to virulence in Xanthomonas oryzae pv. oryzae.

ABSTRACT: Xanthomonas oryzae pv. oryzae (Xoo) causes a damaging bacterial leaf blight disease in rice. Cold shock proteins (Csps) are highly conserved nucleic acid-binding proteins present in various bacterial genera, but relatively little is known about their functions in Xanthomonas. Herein, we identified four Csps (CspA-CspD) in the Xoo PXO99A strain. Deletion of cspA decreased cold adaptation and a few known pathogenic factors, including bacterial pathogenicity, biofilm formation and polysaccharide production. Furthermore, we performed transcriptomic and chromosome immunoprecipitation (ChIP) experiments to identify direct targets of CspA and to determine its DNA-binding sequence. Integrative data analysis revealed that CspA directly regulates two genes, PXO_RS11830 and PXO_RS01060, by binding to a conserved CCAAT sequence in the promoter region. We generated single-deletion mutants of each gene and the results indicate that both are responsible for Xanthomonas pathogenicity. In addition, quantitative real-time polymerase chain reaction and western blotting showed that CspA suppressed the expression of its direct targets. In summary, our study clarifies the characteristics of Csps in Xanthomonas and greatly advances our understanding of the mechanisms underlying the contribution of CspA to bacterial virulence.

SUBMITTER: Wu L

PROVIDER: S-EPMC6637868 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Contribution of the cold shock protein CspA to virulence in Xanthomonas oryzae pv. oryzae.

Wu Liming L Ma Liumin L Li Xi X Huang Ziyang Z Gao Xuewen X

Molecular plant pathology 20181116 3

Xanthomonas oryzae pv. oryzae (Xoo) causes a damaging bacterial leaf blight disease in rice. Cold shock proteins (Csps) are highly conserved nucleic acid-binding proteins present in various bacterial genera, but relatively little is known about their functions in Xanthomonas. Herein, we identified four Csps (CspA-CspD) in the Xoo PXO99<sup>A</sup> strain. Deletion of cspA decreased cold adaptation and a few known pathogenic factors, including bacterial pathogenicity, biofilm formation and polysa ...[more]

PMID: 30372574

Similar Datasets

Project description:In Xanthomonas oryzae pv. oryzae, the bacterial blight pathogen of rice, there are over 20 genes encoding GGDEF, EAL, and HD-GYP domains, which are potentially involved in the metabolism of second messenger c-di-GMP. In this study, we focused on the characterization of an EAL domain protein, EdpX1. Deletion of the edpX1 gene resulted in a 2-fold increase in the intracellular c-di-GMP levels, which were restored to the wild-type levels in the complemented ΔedpX1(pB-edpX1) strain, demonstrating that EdpX1 is an active phosphodiesterase (PDE) in X. oryzae pv. oryzae. In addition, colorimetric assays further confirmed the PDE activity of EdpX1 by showing that the E153A mutation at the EAL motif strongly reduced its activity. Virulence assays on the leaves of susceptible rice showed that the ΔedpX1 mutant was severely impaired in causing disease symptoms. In trans expression of wild-type edpX1, but not edpX1 E153A, was able to complement the weakened virulence phenotype. These results indicated that an active EAL domain is required for EdpX1 to regulate the virulence of X. oryzae pv. oryzae. We then demonstrated that the ΔedpX1 mutant was defective in secreting exopolysaccharide (EPS) and forming biofilms. The expression of edpX1 in the ΔedpX1 mutant, but not edpX1 E153A, restored the defective phenotypes to near-wild-type levels. In addition, we observed that EdpX1-green fluorescent protein (EdpX1-GFP) exhibited multiple subcellular localization foci, and this pattern was dependent on its transmembrane (TM) region, which did not seem to directly contribute to the regulatory function of EdpX1. Thus, we concluded that EdpX1 exhibits PDE activity to control c-di-GMP levels, and its EAL domain is necessary and sufficient for its regulation of virulence in X. oryzae pv. oryzae.IMPORTANCE Bacteria utilize c-di-GMP as a second messenger to regulate various biological functions. The synthesis and degradation of c-di-GMP are catalyzed by GGDEF domains and an EAL or HD-GYP domain, respectively. Multiple genes encoding these domains are often found in one bacterial strain. For example, in the genome of X. oryzae pv. oryzae PXO99A, 26 genes encoding proteins containing these domains were identified. Therefore, to fully appreciate the complexity and specificity of c-di-GMP signaling in X. oryzae pv. oryzae, the enzymatic activities and regulatory functions of each GGDEF, EAL, and HD-GYP domain protein need to be elucidated. In this study, we showed that the EAL domain protein EdpX1 is a major PDE to regulate diverse virulence phenotypes through the c-di-GMP signaling pathway.

Dataset Information

Contribution of the cold shock protein CspA to virulence in Xanthomonas oryzae pv. oryzae.

Publications

Contribution of the cold shock protein CspA to virulence in Xanthomonas oryzae pv. oryzae.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets