Mycobacterium tuberculosis H37Rv transcriptional response to antibacterial agents
Ontology highlight
ABSTRACT:
ORGANISM(S): Mycobacterium tuberculosis
SUBMITTER: Shuyi Ma
PROVIDER: E-GEOD-71200 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:Four cultures (four biological replicates) of each of two strains, wild type H37Rv and a deletion mutant for mce3R gene, were grown in in Middlebrook 7H9 medium supplemented with 0.05% Tween 80, or Middlebrook 7H11, supplemented with albumin 0.5%, dextrose 0.4%, and 0.5% glycerol (M7H9-AD-G). <br>Total RNA was extracted from each culture, dyed with Cy5 and hybridised onto two separated microarrays (technical duplicates). <br>In the second channel a mix of genomic DNA from strains H37Rv and AF2122 was dyed with CY3 and used as a common control in all the microarrays.<br>An statistical analysis of microarray data was performed to detect genes with differential expression between genotypes.
2009-06-17 | E-MEXP-2202 | biostudies-arrayexpress
Project description:Background: Conflicting results have been reported about the role of the two-component sensor and transcriptional regulator DosS/DosR, controlling the expression of the dormancy DosR regulon, for in vivo virulence of M. tuberculosis. Here, we have used a new approach to further analyze the relevance of the dosRS system, by driving DosR (Rv3133c) expression under the control of a constitutive promoter (phsp60). Methodology/Principal Findings: M. tuberculosis H37Rv constitutively expressing the transcriptional regulator DosR (Mtb::DosR) was compared to wild type M. tuberculosis (Mtb+/+) for in vitro growth kinetics and expression of the target genes of the DosR dormancy regulon, for in vivo virulence and for immunogenicity in mice. Under aerobic conditions, hsp60-driven DosR induced the expression of 28 out of 39 tested DosR regulon genes. In vitro growth characteristics were comparable for both strains, but Mtb::DosR showed an attenuated in vivo phenotype in immunocompetent mice, as indicated by reduced bacterial replication, reduced pulmonary immunopathology, reduced cachexia and significantly prolonged survival time as compared Mtb+/+. In immunodeficient SCID mice, Mtb::DosR was fully virulent. RT-qPCR analysis revealed a strong and comparable pulmonary TNF-?? and IL-23 expression following intratracheal infection, whereas IL-12 and IL-17 expression was slightly higher with wild type Mtb+/+. Finally, mice persistently infected with Mtb::DosR for 8 months showed five to tenfold higher lung IFN-?? responses against ten of the 48 DosR regulon encoded antigens (Rv1733c, Rv1734, Rv1738, Rv1996, Rv1997, Rv2029c, Rv2623, Rv2627c, Rv2628 and Rv3127) than mice actively infected with Mtb+/+. In spleen however, DosR regulon encoded antigen specific IFN-?? responses were similar in both groups. Conclusions/Significance. Collectively, these results suggest that increased DosR regulon encoded antigen specific pulmonary T cell responses are responsible for the attenuated phenotype of Mtb::DosR and that infection with Mtb::DosR could be used as a new animal model for studying key aspects of latent tuberculosis. Set of arrays that are part of repeated experiments
2012-06-12 | E-GEOD-19838 | biostudies-arrayexpress
Project description:Using cell-based approaches and experimental mouse models for pulmonary TB we unveiled MDSCs as new myeloid populations directly interacting with Mycobacterium tuberculosis (Mtb). MDSCs readily phagocytosed Mtb, released proinflammatory (IL-6, IL-1M-NM-1) and immunomodulatory (IL-10) cytokines while retaining their suppressive capacity. MDSCs were identified at the site of infection in disease-resistant and -susceptible mice during pulmonary TB. Excessive MDSC accumulation in lungs correlated with elevated surface expression of IL-4RM-NM-1 and heightened TB lethality. Microarray experiments were performed as dual-color hybridizations on Agilent mouse whole genome catalog 44K arrays. To compensate for dye-specific effects, a dye-reversal color-swap was applied.
2014-12-21 | E-GEOD-57124 | biostudies-arrayexpress
Project description:In this study, we report the identification of a five-locus copper-inducible regulon in Mycobacterium tuberculosis. The identification of a copper responsive regulon unique to pathogenic Mycobacteria suggests copper homeostasis must be maintained during an infection. WT and mutant Mtb cells were grown in Sauton's minimal media to early stationary phase (OD580 = 1.5) and treated with 500 mM copper sulfate (CuSO4) for four hours or the absence
2010-10-27 | E-GEOD-23498 | biostudies-arrayexpress
Project description:In this study, we report the identification of a five-locus copper-inducible regulon in Mycobacterium tuberculosis. The identification of a copper responsive regulon unique to pathogenic Mycobacteria suggests copper homeostasis must be maintained during an infection. WT and mutant Mtb cells were grown in Sauton’s minimal media to early stationary phase (OD580 = 1.5) and treated with 500 mM copper sulfate (CuSO4) for four hours or the absence.
2011-11-01 | E-GEOD-24968 | biostudies-arrayexpress
Project description:In previously published work, we identified three Mycobacterium tuberculosis sigma (s) factor genes responding to heat shock (sigB, sigE and sigH ). Two of them (sigB and sigE ) also responded to SDS exposure. As these responses to stress suggested that the s factors encoded by these genes could be involved in pathogenicity, we are studying their role in physiology and virulence. In this work, we characterize a sigE mutant of M. tuberculosis H37Rv. The sigE mutant strain was more sensitive than the wild-type strain to heat shock, SDS and various oxidative stresses. It was also defective in the ability to grow inside both human and murine unactivated macrophages and was more sensitive than the wild-type strain to the killing activity of activated murine macrophages. Using microarray technology and quantitative reverse transcriptionÐpolymerase chain reaction (RTÐPCR), we started to define the sigmaE regulon of M. tuberculosis and its involvement in the global regulation of the stress induced by SDS. We showed the requirement for a functional sigE gene for full expression of sigB and for its induction after SDS exposure but not after heat shock. We also identified several genes that are no longer induced when sigmaE is absent. These genes encode proteins belonging to different classes including transcriptional regulators, enzymes involved in fatty acid degradation and classical heat shock proteins. Keywords: genetic modification design and comparative genome hybridization design 15 samples were analyzed. The quality controls were biological replicate and technical replicate
2007-08-02 | E-GEOD-8664 | biostudies-arrayexpress
Project description:The numerous sigma factors present in Mycobacterium tuberculosis (MTB) are indicative of adaptability to different environmental conditions. In this report we describe the sigma factor B (sigB) regulon and the phenotypes of a MTB sigB mutant strain exposed to different stresses like SDS and Diamide. This experiment set compares expression profiles between H37Rv wild type and H37Rv sigB null mutant as well as under different stress conditions. Both H37Rv wild type and H37Rv sigB null mutants were treated with either 0.05% SDS or 5mM Diamide for 60 min and their expression profiles were compared with untreated wild type or mutant controls. Biological Replicate
2010-06-25 | E-GEOD-15976 | biostudies-arrayexpress
Project description:Like other bacterial species, Mycobacterium tuberculosis has multiple sigma (s) factors encoded in its genome. In previously published work, we and others have shown that mutations in some of these transcriptional activators render M. tuberculosis sensitive to various environmental stresses and, in some cases, cause attenuated virulence phenotypes. In this paper, we characterize a M. tuberculosis mutant lacking the ECF s factor sigma-H. This mutant was more sensitive than the wild type to heat shock and to various oxidative stresses, but did not show decreased ability to grow inside macrophages. Using quantitative reverse transcription-PCR and microarray technology, we have started to define the sigma-H regulon and its involvement in the global regulation of the response to heat shock and the thiol-specific oxidizing agent diamide. We identified 48 genes whose expression increased after exposure of M. tuberculosis to diamide; out of these, 39 were not induced in the sigH mutant, showing their direct or indirect dependence on sigma-H. Some of these genes encode proteins whose predicted function is related to thiol metabolism, such as thioredoxin, thioredoxin reductase and enzymes involved in cysteine and molybdopterine biosynthesis. Other genes under sigma-H control encode transcriptional regulators such as sigB, sigE, and sigH itself. Keywords: comparative genome hybridization design and genetic modification design 15 samples were analyzed. The quality controls were biological replicate and technical replicate
2007-08-03 | E-GEOD-8689 | biostudies-arrayexpress
Project description:In previously published work, we identified three Mycobacterium tuberculosis sigma (s) factor genes responding to heat shock (sigB, sigE and sigH ). Two of them (sigB and sigE ) also responded to SDS exposure. As these responses to stress suggested that the s factors encoded by these genes could be involved in pathogenicity, we are studying their role in physiology and virulence. In this work, we characterize a sigE mutant of M. tuberculosis H37Rv. The sigE mutant strain was more sensitive than the wild-type strain to heat shock, SDS and various oxidative stresses. It was also defective in the ability to grow inside both human and murine unactivated macrophages and was more sensitive than the wild-type strain to the killing activity of activated murine macrophages. Using microarray technology and quantitative reverse transcriptionÐpolymerase chain reaction (RTÐPCR), we started to define the sigmaE regulon of M. tuberculosis and its involvement in the global regulation of the stress induced by SDS. We showed the requirement for a functional sigE gene for full expression of sigB and for its induction after SDS exposure but not after heat shock. We also identified several genes that are no longer induced when sigmaE is absent. These genes encode proteins belonging to different classes including transcriptional regulators, enzymes involved in fatty acid degradation and classical heat shock proteins.
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