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GSE56133
Escherichia coli str. k-12 substr. mg1655
26 Downloadable Samples
Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
Deeper understanding of antibiotic-induced physiological responses is critical to identifying means for enhancing our current antibiotic arsenal. Bactericidal antibiotics with diverse targets have been hypothesized to kill bacteria, in part, by inducing production of damaging reactive species. This notion has been supported by many groups, but recently challenged. Here we robustly test the hypothesis using biochemical, enzymatic and biophysical assays along with genetic and phenotypic experiments. We first used a novel intracellular hydrogen peroxide (H2O2) sensor, together with a chemically diverse panel of fluorescent dyes sensitive to an array of reactive species, to demonstrate that antibiotics broadly induce redox stress. Subsequent gene expression analyses reveal that complex antibiotic-induced oxidative stress responses are distinct from canonical responses generated by supra-physiological levels of H2O2. We next developed a method to dynamically quantify cellular respiration and found that bactericidal antibiotics elevate oxygen consumption, indicating significant alterations to bacterial redox physiology. We further show that catalase or DNA mismatch repair enzyme overexpression, as well as antioxidant pre-treatment limit antibiotic lethality, indicating that reactive oxygen species causatively contribute to antibiotic killing. Critically, the killing efficacy of antibiotics was diminished under strict anaerobic conditions, but could be enhanced by exposure to molecular oxygen or addition of alternative electron acceptors, suggesting that environmental factors play a role in killing cells physiologically primed for death. This work provides direct evidence that bactericidal antibiotics, downstream of their target-specific interactions, induce complex redox alterations that contribute to cellular damage and death, thus supporting an evolving, expanded model of antibiotic lethality.
Publication Title
Antibiotics induce redox-related physiological alterations as part of their lethality.
Sample Metadata Fields
Treatment
View Samples- Pseudomonas aeruginosa pao1
- 12 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
This study examines the mechanisms underlying fumarate- and glyoxylate-mediated changes in tobraymcyin sensitivity in PAO1 cells
Publication Title
Carbon Sources Tune Antibiotic Susceptibility in Pseudomonas aeruginosa via Tricarboxylic Acid Cycle Control.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 16 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
A Distinct Gene Module for Dysfunction Uncoupled from Activation in Tumor-Infiltrating T Cells.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 594 Downloadable Samples
- Affymetrix HT Mouse Genome 430A Array (htmg430a)
Description
We measured the genome-wide expression changes induced by 29 compounds targeting HDACs, DNMTs, histone lysine methyltransferases (HKMTs), and protein arginine methyltransferases (PRMTs) in pancreatic - and -cell lines.
Publication Title
Chromatin-targeting small molecules cause class-specific transcriptional changes in pancreatic endocrine cells.
Sample Metadata Fields
Cell line, Treatment
View Samples- Mus musculus, Homo sapiens
- 8 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Musashi-2 regulates normal hematopoiesis and promotes aggressive myeloid leukemia.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Reprogramming factor expression initiates widespread targeted chromatin remodeling.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 18 Downloadable Samples
- Affymetrix HT Human Genome U133A Array (hthgu133a)
Description
Expression data from treatment of actinomycin D (2.5uM) and triptolide (500 nM) on MCF7 cells for 2, 4 and 6 hours.
Publication Title
Chemical genomics identifies small-molecule MCL1 repressors and BCL-xL as a predictor of MCL1 dependency.
Sample Metadata Fields
Cell line, Compound, Time
View Samples- Mus musculus
- 16 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Reversing the dysfunctional T cell state that arises in cancer and chronic viral infections is the focus of therapeutic interventions; however, current therapies are effective in only some patients and some tumor types. To gain a deeper molecular understanding of the dysfunctional T cell state, we analyzed population and single-cell RNA profiles of CD8+ tumor-infiltrating lymphocytes (TILs) and used genetic perturbations to identify a distinct gene module for T cell dysfunction that can be uncoupled from T cell activation. This distinct dysfunction module is downstream of intracellular metallothioneins that regulate zinc metabolism and can be identified at single-cell resolution. We further identify Gata-3, a zinc-finger transcription factor in the dysfunctional module, as a regulator of dysfunction, and use CRISPR/Cas9 genome editing to show that it drives a dysfunctional phenotype in CD8+ TILs. Our results open novel avenues for targeting dysfunctional T cell states, while leaving activation programs intact.
Publication Title
A Distinct Gene Module for Dysfunction Uncoupled from Activation in Tumor-Infiltrating T Cells.
Sample Metadata Fields
Specimen part
View Samples- Caenorhabditis elegans
- 6 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
RIP-chip-SRM : a New Combinatorial Large Scale Approach Identifies a Set of Translationally Regulated bantam/miR 58 Targets in C. elegans
Publication Title
RIP-chip-SRM--a new combinatorial large-scale approach identifies a set of translationally regulated bantam/miR-58 targets in C. elegans.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix HT Human Genome U133A Array (hthgu133a)
Description
We explored the effects of dexamethasone and lenalidomide, individually and in combination, on the differentiation of primary human bone marrow progenitor cells in vitro. Both agents promote erythropoiesis, increasing the absolute number of erythroid cells produced from normal CD34+ cells and from CD34+ cells with the types of ribosome dysfunction found in DBA and del(5q) MDS. However, the drugs had distinct effects on the production of erythroid progenitor colonies; dexamethasone selectively increased the number burst-forming units-erythroid (BFU-E), while lenalidomide specifically increased colony-forming units-erythroid (CFU-E). Use of the drugs in combination demonstrates that their effects are not redundant.
Publication Title
Dexamethasone and lenalidomide have distinct functional effects on erythropoiesis.
Sample Metadata Fields
Specimen part, Treatment
View Samples