Project description:Four stable and robust TCE-dechlorinating microbial communities were enriched from TCE-contaminated groundwater under four different conditions exploring two parameters, high and low methanogenic activity (Meth and NoMeth), with and without vitamin B12 supplement (MethB12 and NoMethB12, Meth and NoMeth, respectively). Identical amounts of lactate (2.7 mmol) and TCE (20 μl) were supplied as electron donor and electron acceptor. All four cultures were capable of reductively dechlorinating TCE to VC and ethene. Genomic DNA of the four enrichments was applied on a quad-Dhc-genome microarray in order to characterize the gene content of Dehalococcoides species present in the four enrichments
Project description:To simulate in vitro different oxidative stress exposures, AC16 cells were cultured either under physioxia (5% oxygen) or normoxia (21% oxygen), and were consequently harvested either under physioxia or normoxia.
Project description:Four stable and robust TCE-dechlorinating microbial communities were enriched from TCE-contaminated groundwater under four different conditions exploring two parameters, high and low methanogenic activity (Meth and NoMeth), with and without vitamin B12 supplement (MethB12 and NoMethB12, Meth and NoMeth, respectively). Identical amounts of lactate (2.7 mmol) and TCE (20 M-NM-<l) were supplied as electron donor and electron acceptor. All four cultures were capable of reductively dechlorinating TCE to VC and ethene. Genomic DNA of the four enrichments was applied on a quad-Dhc-genome microarray in order to characterize the gene content of Dehalococcoides species present in the four enrichments The genomic DNA of four enrichment cultures completely dechlorinated TCE to VC and ethene was used on the microarray to query Dehalococcoides species present in the mixed cultures.
Project description:The TaRGET (Toxicant Exposures and Responses by Genomic and Epigenomic Regulators of Transcription) program is a research consortium funded by the National Institute of Environmental Health Sciences (NIEHS). The goal of the collaboration is to address the role of environmental exposures in disease pathogenesis as a function of epigenome perturbation, including understanding the environmental control of epigenetic mechanisms and assessing the utility of surrogate tissue analysis in mouse models of disease-relevant environmental exposures (https://targetepigenomics.org).
Project description:In order to understand how Pseudomonas aeruginosa responds to low oxygen we grew strain PAO1 with 3 different oxygen concentrations: 2%, 0.4% and 0% supplemented with nitrate as an electron acceptor. Gene expression under these conditions was compared to that of cells grown with 20% oxygen. Keywords: Comparison of transcriptome profiles
Project description:The genomes of three newly isolated Dehalococcoides strains (11a, 11a5 and MB) were compared against known genomes in the Dehalococcoides genus via a microarray targeting four sequenced Dehalococcoides strains (195, CBDB1, BAV1, and VS). All three strains exhibit different dechlorination patterns, with strains 11a dechlorinating TCE to ethene, 11a5 dechlorinating TCE to VC and MB dechlorinating PCE only to isomers of DCE. Hybridization of their respective genomic DNA to the microarrays showed that the genomes of strains 11a and 11a5 show great similarity to each other and to strains CBDB1 and BAV1 of the Pinellas subgroup, while strain MB shows strong genome similarity to members of the Cornell subgroup. All genes within the respective subgroups that were not detected by microarray are within the respective high plasticity regions or integrated elements of the sequenced strains. A large number of reductive dehalogenase (RDase)-encoding genes are present within each genome, and the presence of the vcrA and tceA genes in strains 11a and 11a5 respectively, and the absence of any of the four functionally-characterized chlorinated ethene RDases (pceA, tceA, vcrA, bvcA) within strain MB appear to dictate chlorinated ethene usages regardless of the respective core genome phylogeny of the three strains. Considering the current data set together with previous comparative genomics results from application of the Dehalococcoides genus microarray to two other un-sequenced strains, the observed incongruence between the core genome phylogeny and chlorinated ethene usage of Dehalococcoides strains is likely driven by horizontal gene transfer of functional RDases. The other genomic features that are repeatedly observed in the microarray analyses of all five un-sequenced Dehalococcoides strains as well as the environmental implications on this work are presented in this study. The genomic DNA (gDNA) of each culture was analyzed in triplicate. gDNA from the two newly isolated Dehalococcoides strains 11a and 11a5 were analyzed.
Project description:Transcriptome profiles of an aerobic photosynthetic bacterium Roseobacter denitrificans OCh114 grown under different oxygen tension and light irradiation conditions were determined by NimbleGen Prokaryotic Expression array (12x135K).
Project description:This series compares the effects that two pharmacologically distinct ligands at the mitochondrial peripheral-type benzodiazepine receptor (Bzrp) has on gene expression in early mouse embryos cultured under different oxygen levels. Mouse embryos averaging 16-18 somite pairs were explanted on 9 d.p.c. and grown in culture under optimal oxygenation (21% oxygen, hyperbaric with respect to arterial blood = 80-100 mmHg). Most embryos (>90%) develop normally in over a 24h culture period. When embryos receive suboptimal oxygenation for 2.0h (5% oxygen, similar to venous blood = 38-40 mmHg) a high percentage of them (>60%) go on to develop abnormally or else fail. These hypoxic embryos are remediated with 5 uM PK11195 to ~25% malformation rate. Cultured embryos were exposed to different oxygen levels (5% or 21%) in the presence of the Bzrp ligands PK11195 (Bzrp antagonist) versus Ro5-4864 (Bzrp agonist). The sampling time was guided by p53 protein induction with hypoxia, and remediation with PK11195, at 4.0h of culture and exposures. Thus all measurements were on RNA from the prosencephalon collected 2.0h after start of the test period on 9 d.p.c. Keywords = peripheral benzodiazepine receptor Keywords = oxygen sensing Keywords = Bzrp ligands Keywords = PK11195 Keywords = Ro5-4864 Keywords = embryo Keywords = p53 protein induction
Project description:This series compares the effects that two pharmacologically distinct ligands at the mitochondrial peripheral-type benzodiazepine receptor (Bzrp) has on gene expression in early mouse embryos cultured under different oxygen levels. Mouse embryos averaging 16-18 somite pairs were explanted on 9 d.p.c. and grown in culture under optimal oxygenation (21% oxygen, hyperbaric with respect to arterial blood = 80-100 mmHg). Most embryos (>90%) develop normally in over a 24h culture period. When embryos receive suboptimal oxygenation for 2.0h (5% oxygen, similar to venous blood = 38-40 mmHg) a high percentage of them (>60%) go on to develop abnormally or else fail. These hypoxic embryos are remediated with 5 uM PK11195 to ~25% malformation rate. Cultured embryos were exposed to different oxygen levels (5% or 21%) in the presence of the Bzrp ligands PK11195 (Bzrp antagonist) versus Ro5-4864 (Bzrp agonist). The sampling time was guided by p53 protein induction with hypoxia, and remediation with PK11195, at 4.0h of culture and exposures. Thus all measurements were on RNA from the prosencephalon collected 2.0h after start of the test period on 9 d.p.c. Keywords = peripheral benzodiazepine receptor Keywords = oxygen sensing Keywords = Bzrp ligands Keywords = PK11195 Keywords = Ro5-4864 Keywords = embryo Keywords = p53 protein induction Keywords: ordered