Identification of a novel LysR-type regulator involved in virulence and primary and secondary metabolism of Burkholderia pseudomallei.
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA434734 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Burkholderia pseudomallei is a soil-dwelling bacterium which has to survive not only under harsh environmental conditions, but also within various hosts where it can cause the infectious disease melioidosis. The ability, to quickly adapt to these different conditions, is based on its huge genome which encodes for complex regulatory networks. Among them are more than 60 genes belonging to the group of LysR-type transcriptional regulators (LTTRs). Here we analyzed a B. pseudomallei mutant harboring a transposon in the gene BPSL0117 annotated as a LTTR, which we named gvmR (globally acting virulence and metabolism regulator). The gvmR mutant displayed a growth defect in minimal medium and macrophages in comparison with the wild type. Moreover, inactivation of GvmR rendered B. pseudomallei avirulent in mice indicating a critical role of GvmR in infection. These defects of the mutant were rescued by ectopic expression of gvmR. To identify genes whose expression is modulated by GvmR, global transcriptome analysis of the B. pseudomallei wild type and gvmR mutant was performed using whole genome tiling microarrays. Transcript levels of 190 and 142 genes were found to be up- and downregulated in the gvmR mutant relative to the wild type. Among the most downregulated genes in the gvmR mutant were important virulence factor genes (T3SS3, T6SS1 and T6SS2), which might provide an explanation for the virulence defect of the gvmR mutant. In addition, expression of genes related to amino acid synthesis, glyoxylate shunt, iron-sulfur cluster assambly and syrbactin metabolism (secondary metabolite) was decreased in the mutant. Furthermore, inactivation of GvmR increased expression of genes involved in pyruvate metabolism, ATP synthesis, malleobactin and porin genes. Quantitative RT-PCR verified the differential expression of 27 selected genes. In summary, our data show that GvmR acts as an activating and repressing global regulator that is required to coordinate expression of a diverse set of metabolic and virulence genes for survival in the animal host and under nutrient limitation.
2018-05-02 | GSE110883 | GEO
Project description:Burkholderia pseudomallei, the etiological agent of melioidosis in humans and animals, often occupies environmental niches and infection sites characterized by limited concentrations of oxygen. Versatile genomic features enable this pathogen to maintain its physiology and virulence under hypoxia, but the crucial regulatory networks employed to switch from oxygen dependent respiration to alternative terminal electron acceptors (TEA) like nitrate, remains poorly understood. Here, we combined a Tn5 transposon mutagenesis screen and an anaerobic growth screen to identify a two-component signal transduction system with homology to RegAB. We show that RegAB is not only essential for anaerobic growth, but also for full virulence in cell lines and a mouse infection model. Further investigations of the RegAB regulon, using a global transcriptomic approach, identified 20 additional regulators under transcriptional control of RegAB, indicating a superordinate role of RegAB in the B. pseudomallei anaerobiosis regulatory network. Of the 20 identified regulators, NarX/L and a FNR homolog were selected for further analyses and a role in adaptation to anaerobic conditions was demonstrated. Growth experiments identified nitrate and intermediates of the denitrification process as the likely signal activateing RegAB, NarX/L, and probably of the downstream regulators Dnr or NsrR homologs. While deletions of individual genes involved in the denitrification process demonstrated their important role in anaerobic fitness, they showed no effect on virulence. This further highlights the central role of RegAB as the master regulator of anaerobic metabolism in B. pseudomallei and that the complete RegAB-mediated response is required to achieve full virulence. In summary, our analysis of the RegAB-dependent modulon and its interconnected regulons revealed a key role for RegAB of B. pseudomallei in the coordination of the response to hypoxic conditions and virulence, in the environment and the host.
2021-05-17 | GSE159521 | GEO
Project description:Burkholderia pseudomallei is a soil-dwelling bacterium able to survive not only under adverse environmental conditions, but also within various hosts which can lead to the disease melioidosis. The capability of B. pseudomallei to adapt to environmental changes is facilitated by the large number of regulatory proteins encoded by its genome. Among them are more than 60 uncharacterized LysR-type transcriptional regulators (LTTRs). Here we analyzed a B. pseudomallei mutant harboring a transposon in the gene BPSL0117 annotated as a LTTR, which we named gvmR (globally acting virulence and metabolism regulator). The gvmR mutant displayed a growth defect in minimal medium and macrophages in comparison with the wild type. Moreover, disruption of gvmR rendered B. pseudomallei avirulent in mice indicating a critical role of GvmR in infection. These defects of the mutant were rescued by ectopic expression of gvmR. To identify genes whose expression is modulated by GvmR, global transcriptome analysis of the B. pseudomallei wild type and gvmR mutant was performed using whole genome tiling microarrays. Transcript levels of 190 genes were upregulated and 141 genes were downregulated in the gvmR mutant relative to the wild type. Among the most downregulated genes in the gvmR mutant were important virulence factor genes (T3SS3, T6SS1, and T6SS2), which could explain the virulence defect of the gvmR mutant. In addition, expression of genes related to amino acid synthesis, glyoxylate shunt, iron-sulfur cluster assembly, and syrbactin metabolism (secondary metabolite) was decreased in the mutant. On the other hand, inactivation of GvmR increased expression of genes involved in pyruvate metabolism, ATP synthesis, malleobactin, and porin genes. Quantitative real-time PCR verified the differential expression of 27 selected genes. In summary, our data show that GvmR acts as an activating and repressing global regulator that is required to coordinate expression of a diverse set of metabolic and virulence genes essential for the survival in the animal host and under nutrient limitation.
| S-EPMC5964159 | biostudies-literature
Project description:Burkholderia mallei and Burkholderia pseudomallei are both potential biological threats agents. Melioidosis caused by B. pseudomallei is endemic in Southeast Asia and Northern Australia, while glanders caused by B. mallei infections are rare. Here we studied the proteomes of different B. mallei and B. pseudomallei isolates to determine species specific characteristics. Analyzing the expressed proteomes of B. mallei and B. pseudomallei revealed differences between B. mallei and B. pseudomallei but also between isolates from the same species. Expression of multiple virulence factors and proteins of several PKS/NRPS clusters was demonstrated. Proteome analysis can be used not only to identify bacteria but also to characterize the expression of important factors that putatively contribute to pathogenesis of B. mallei and B. pseudomallei.
2022-12-15 | PXD028126 | Pride
Project description:The gene expression profiles were investigated and compared in spleen, lungs and liver of susceptible (BALB/c) and resistant (C57BL/6) hosts to identify genes participated in survival and virulence functions encoded in the B. pseudomallei genome. Subsequently, genes with unknown function and located with virulence gene clusters or suspected to be transcription regulator were selected for a novel virulence gene investigation DNA microarray was used to compare gene expression profiles of B. pseudomallei 1909a in spleen, lung and liver of infection-susceptible BALB/c mice (Th2 prototype) and infection-resistant C57BL/6 mice, (Th1 prototype) during an acute infection. The gene expression profile of B. pseudomallei in culture medium at mid-log phase was used to identify genes that expressed higher or lower in vivo when compared to the in vitro gene profile KEYWORDS: Gene expression
2014-09-12 | E-GEOD-51369 | biostudies-arrayexpress
Project description:The gene expression profiles were investigated and compared in spleen, lungs and liver of susceptible (BALB/c) and resistant (C57BL/6) hosts to identify genes participated in survival and virulence functions encoded in the B. pseudomallei genome. Subsequently, genes with unknown function and located with virulence gene clusters or suspected to be transcription regulator were selected for a novel virulence gene investigation
2014-09-12 | GSE51369 | GEO
Project description:Purpose: The goal of this study was to identify Staphylococcus aureus genes which are important during establishment of metastatic infections in bloodstream infections. Methods: Pooled mariner transposon mutant libraries were generated as previously described (PMID: 27185949). The libraries were sequenced on the Illumina HiSeq 2500 platform with the transposon-specific oligonucleotide primer Himar1-Seq. Illumina adapter sequences were removed via cutadapt version 1.2.1. The reads were filtered for size (>16 bp) and to contain the signature transposon inverted repeat. Reads were mapped to the Staphylococcus aureus 6850 genome (RefSeq accession NC_022222.1) by Bowtie2 v2.1.0. Identification of depleted and enriched mutants was performed via DESeq2 version 1.6.2. Results: S. aureus genes were identified which were upregulated or downregulated upon iduced expression of the LysR-type transcriptional regulator RSAU_000852 in Staphylococcus aureus 6850. Conclusions: Our study identifies a gene for a LysR-type transcription regulator, which is involved in metabolic adaptation of the pathogen during colonization of secondary infection sites in a bloodstream infection model.
2020-09-08 | GSE139513 | GEO
Project description:Burkholderia pseudomallei is the causative agent of melioidosis which is endemic to Southeast Asia and Northern Australia. It is a Gram-negative soil and water bacterium that represents a potential bioterrorism threat. Colony morphology variation is a remarkable feature in primary clinical cultures of B. pseudomallei. Differences in expression of several potential virulence and survival genes were believed to be associated with B. pseudomallei colony morphology variants. Microarrray approach was used to investigate alterations of the global B. pseudomallei transcriptome profile at the mid-logarithmic phase of growth, among the wild type (WT) and small colony variant (SCV) of B. pseudomallei pre- and post-exposed to human lung epithelial cells, A549. Generally, SCV pre- and post-exposed have lower metabolic requirements and consume lesser energy than WT pre- and post-exposed to A549; however, both WT and SCV may limit their metabolic activity during the infection of A549 cells and this is indicated by the down-regulation of genes implicated in metabolism of amino acids, carbohydrate, lipid, and other amino acids, and biodegradation of xenobiotics. On the other hand, many well-known virulence and survival factors including T3SS, T6SS, fimbriae, capsular polysaccharides, drug resistance and stress response were up-regulated in both WT and SCV pre- and post-exposed to A549 cells. Several virulence factors expressed at the mid-logarithmic phase of growth. Microarray analysis on the different morphotypes demonstrated the essential difference in bacterial response associated with virulence and survival pre- and post-exposed to A549 cells.
2016-10-12 | GSE87827 | GEO
Project description:Objectives: The Burkholderia pseudomallei bprR and bprS genes are predicted to encode the response regulator and sensor kinase components respectively of a two component signal transduction system. Inactivation of either single component of this two component signal transduction system led to attenuation of B. pseudomallei virulence and also reduced motility. However, inactivation of both components resulted in wild-tpe virulence and motility. Therefore, we used RNA-seq to compare the transcritptomes of the three mutant strains (bprR single, bprS single, bprRS double mutant) with the wild-type parent strain in order to identify the genes differenty regulated in the different mutants.
2016-04-27 | GSE77970 | GEO
Project description:Burkholderia pseudomallei can adapt to and thrive in a variety of environments, including soil and water, and also can infect different hosts, including humans, leading to the tropical disease melioidosis. Modulation of gene and protein expression is one of this pathogen's adaptive survival mechanisms, which could lead to changes in the bacteria's cell membrane, metabolism, and virulence. To better understand bacterial adaptation and host-pathogen interactions, this study compared the expression profiles of B. pseudomallei from infected mice to B. pseudomallei cultivated in soil extract media. B. pseudomallei in vivo was created by infecting mice through the intraperitoneal route and harvesting the spleens on day 5 post infection. Total RNA was isolated and sequenced from the harvested spleen. Sequence reads were mapped to the B. pseudomallei UKMD286 strain genome sequence.
2022-07-22 | E-MTAB-11200 | biostudies-arrayexpress