Dataset Information

Comparison of the transcriptomes of a Burkholeria pseudomallei bprR [bpss0688] mutant, a bprS [bpss0687] mutant and a bprRS double mutant with the wild-type B. pseudomallei K96243 parent strain.

ABSTRACT: 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. Overall design: Methods: RNA sequencing was employed to determine the transcriptomes of three mutant strains (bprR single, bprS single, bprRS double mutant) with the wild-type parent strain B. pseudomallei K96243. B. pseudomallei parent strain K96243 and the directed bprS, bprR and bprRS mutants were grown overnight at 37 °C in LB with appropriate antibiotics (K96243 in gentamicin 64 µg/ml; mutants in gentamicin 64 µg/ml and tetracycline 25 µg/ml). Strains were subcultured 1/50 into fresh antibiotic-free medium and grown at 37 °C with shaking (200 rpm) to an OD600 of 0.5. The cells were harvested by centrifugation, and RNA purified using Trizol reagent (Gibco/BRL) as specified by the manufacturer. RNA was DNase treated using the TURBO DNA-free kit (Ambion), followed by processing with a QIAGEN RNeasy kit clean-up with on-column DNase digestion as per the manufacturer’s instruction. Double-stranded cDNA synthesis and high-throughput RNA-seq were performed as described previously (Henry R, Crane B, Powell D, Deveson Lucas D, et al: The transcriptomic response of Acinetobacter baumannii to colistin and doripenem alone and in combination in an in vitro pharmacokinetics/pharmacodynamics model. J Antimicrob Chemother. 2015; 70:1303-1313). For each strain three biological replicates were sequenced.

INSTRUMENT(S): Illumina MiSeq (Burkholderia pseudomallei K96243)

SUBMITTER: David Richard Powell

PROVIDER: GSE77970 | GEO | 2016-04-27

SECONDARY ACCESSION(S): PRJNA312225

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
	GSE77970_counts.csv.gz	Csv

Items per page:

1 - 1 of 1

Publications

Perturbation of the two-component signal transduction system, BprRS, results in attenuated virulence and motility defects in Burkholderia pseudomallei.

Lazar Adler Natalie R NR Allwood Elizabeth M EM Deveson Lucas Deanna D Harrison Paul P Watts Stephen S Dimitropoulos Alexandra A Treerat Puthayalai P Alwis Priyangi P Devenish Rodney J RJ Prescott Mark M Govan Brenda B Adler Ben B Harper Marina M Boyce John D JD

BMC genomics 20160504

<h4>Background</h4>Burkholderia pseudomallei is the causative agent of melioidosis, a severe invasive disease of humans and animals. Initial screening of a B. pseudomallei signature-tagged mutagenesis library identified an attenuated mutant with a transposon insertion in a gene encoding the sensor component of an uncharacterised two-component signal transduction system (TCSTS), which we designated BprRS.<h4>Results</h4>Single gene inactivation of either the response regulator gene (bprR) or the ...[more]

PMID: 27147217

Similar Datasets

Project description:Melioidosis, caused by the Gram-negative bacterium Burkholderia pseudomallei, is a major cause of sepsis and mortality in endemic regions of Southeast Asia and Northern Australia. B. pseudomallei is a potential bioterrorism agent due to its high infectivity, especially via inhalation, and its inherent resistance to antimicrobials. There is currently no vaccine for melioidosis and antibiotic treatment can fail due to innate drug resistance, delayed diagnosis and treatment, or insufficient duration of treatment. A well-characterized animal model that mimics human melioidosis is needed for the development of new medical countermeasures. This study first characterized the disease progression of melioidosis in the African green monkey (AGM) and rhesus macaque (RM) for non-human primate model down-selection. All AGMs developed acute lethal disease similar to that described in human acute infection following exposure to aerosolized B. pseudomallei strain HBPUB10134a. Only 20% of RMs succumbed to acute disease. Disease progression, immune response and pathology of two other strains of B. pseudomallei, K96243 and MSHR5855, were also compared using AGMs. These three B. pseudomallei strains represent a highly virulent strain from Thailand (HBPUB101034a), a highly virulent strains from Australia (MSHR5855), and a commonly used laboratory strains originating from Thailand (K96243). Animals were observed for clinical signs of infection and blood samples were analyzed for cytokine responses, blood chemistry and leukocyte changes in order to characterize bacterial infection. AGMs experienced fever after exposure to aerosolized B. pseudomallei at the onset of acute disease. Inflammation, abscesses and/or pyogranulomas were observed in lung with all three strains of B. pseudomallei. Inflammation, abscesses and/or pyogranulomas were observed in lymph nodes, spleen, liver and/or kidney with B. pseudomallei, HBPUB10134a and K96243. Additionally, the Australian strain MSHR5855 induced brain lesions in one AGM similar to clinical cases of melioidosis seen in Australia. Elevated serum levels of IL-1?, IL-1 receptor antagonist, IL-6, MCP-1, G-CSF, HGF, IFN?, MIG, I-TAC, and MIP-1? at terminal end points can be significantly correlated with non-survivors with B. pseudomallei infection in AGM. The AGM model represents an acute model of B. pseudomallei infection for all three strains from two geographical locations and will be useful for efficacy testing of vaccines and therapeutics against melioidosis. In summary, a dysregulated immune response leading to excessive persistent inflammation and inflammatory cell death is the key driver of acute melioidosis. Early intervention in these pathways will be necessary to counter B. pseudomallei and mitigate the pathological consequences of melioidosis.

Project description:Infection by the Gram-negative pathogen Burkholderia pseudomallei results in the disease melioidosis, acquired from the environment in parts of southeast Asia and northern Australia. Clinical symptoms of melioidosis range from acute (fever, pneumonia, septicemia, and localized infection) to chronic (abscesses in various organs and tissues, most commonly occurring in the lungs, liver, spleen, kidney, prostate and skeletal muscle), and persistent infections in humans are difficult to cure. Understanding the basic biology and genomics of B. pseudomallei is imperative for the development of new vaccines and therapeutic interventions. This formidable task is becoming more tractable due to the increasing number of B. pseudomallei genomes that are being sequenced and compared. Here, we compared three B. pseudomallei genomes, from strains MSHR668, K96243 and 1106a, to identify features that might explain why MSHR668 is more virulent than K96243 and 1106a in a mouse model of B. pseudomallei infection. Our analyses focused on metabolic, virulence and regulatory genes that were present in MSHR668 but absent from both K96243 and 1106a. We also noted features present in K96243 and 1106a but absent from MSHR668, and identified genomic differences that may contribute to variations in virulence noted among the three B. pseudomallei isolates. While this work contributes to our understanding of B. pseudomallei genomics, more detailed experiments are necessary to characterize the relevance of specific genomic features to B. pseudomallei metabolism and virulence. Functional analyses of metabolic networks, virulence and regulation shows promise for examining the effects of B. pseudomallei on host cell metabolism and will lay a foundation for future prediction of the virulence of emerging strains. Continued emphasis in this area will be critical for protection against melioidosis, as a better understanding of what constitutes a fully virulent Burkholderia isolate may provide for better diagnostic and medical countermeasure strategies.

Project description:Burkholderia pseudomallei and Burkholderia mallei cause the diseases melioidosis and glanders, respectively. A well-studied aspect of pathogenesis by these closely-related bacteria is their ability to invade and multiply within eukaryotic cells. In contrast, the means by which B. pseudomallei and B. mallei adhere to cells are poorly defined. The purpose of this study was to identify adherence factors expressed by these organisms.Comparative sequence analyses identified a gene product in the published genome of B. mallei strain ATCC23344 (locus # BMAA0649) that resembles the well-characterized Yersinia enterocolitica autotransporter adhesin YadA. The gene encoding this B. mallei protein, designated boaA, was expressed in Escherichia coli and shown to significantly increase adherence to human epithelial cell lines, specifically HEp2 (laryngeal cells) and A549 (type II pneumocytes), as well as to cultures of normal human bronchial epithelium (NHBE). Consistent with these findings, disruption of the boaA gene in B. mallei ATCC23344 reduced adherence to all three cell types by ~50%. The genomes of the B. pseudomallei strains K96243 and DD503 were also found to contain boaA and inactivation of the gene in DD503 considerably decreased binding to monolayers of HEp2 and A549 cells and to NHBE cultures.A second YadA-like gene product highly similar to BoaA (65% identity) was identified in the published genomic sequence of B. pseudomallei strain K96243 (locus # BPSL1705). The gene specifying this protein, termed boaB, appears to be B. pseudomallei-specific. Quantitative attachment assays demonstrated that recombinant E. coli expressing BoaB displayed greater binding to A549 pneumocytes, HEp2 cells and NHBE cultures. Moreover, a boaB mutant of B. pseudomallei DD503 showed decreased adherence to these respiratory cells. Additionally, a B. pseudomallei strain lacking expression of both boaA and boaB was impaired in its ability to thrive inside J774A.1 murine macrophages, suggesting a possible role for these proteins in survival within professional phagocytic cells.The boaA and boaB genes specify adhesins that mediate adherence to epithelial cells of the human respiratory tract. The boaA gene product is shared by B. pseudomallei and B. mallei whereas BoaB appears to be a B. pseudomallei-specific adherence factor.