Effects of Escherichia coli global gene expression due to microfluidic processing
Ontology highlight
ABSTRACT:
ORGANISM(S): Escherichia coli CFT073
SUBMITTER: Senthil Gandi
PROVIDER: E-GEOD-68064 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Treatment failures of antibiotic therapy are of major concern and can be caused by a misalignment of the antibiotic susceptibility determined in vitro with the behaviour of the pathogen in the patient. The aim of this study was to investigate the transcriptomic response of the uropathogenic strain E. coli CFT073 to antibiotic treatment in blood stream infection (BSI) models in order to understand and avoid antibiotic therapy failures in urosepsis treatments. Blood stream infection models were established by growing E. coli CFT073 in pooled human serum with and without ciprofloxacin and compared to Iso-sensitest medium. The antibiotic challenge was introduced at mid-logarithmic phase of growth of the organism to depict a clinical scenario . Global gene expression profiling of these conditions was examined using commercial DNA microarrays. The organismâs metabolic genes appeared to be regulated differently in each medium, this indicated that the bacterial growth regulation were different between the models. Bacterial growth in human serum mainly involved regulations of amino acid synthesis/utilisation such as glycine, arginine, thiamine, regulations of fimbrial proteins and bacteriophage genes. When comparing the responses to antibiotic challenge, bacteria grown in the respective medium displayed specific responses to the antibiotic challenge which were not seen in the other media. The common functions of genes that responded to the ciprofloxacin challenge were SOS response, DNA repair, DNA replication, fimbrial genes and bacteriophage initiation. A subset of the bacteriophage genes showed similar responses between the three models. From genes that were differentially regulated, responses observed in the serum model appeared to have the highest fold changes. In this study we established new models to investigate blood stream infections. They have been used to identify previously unknown differences in the molecular response to antibiotic treatment by the uropathogenic E. coli CFT073 depending on the media. These unique responses will help to unravel the complexity of bloodstream infection and can help to improve the antibiotic therapy that is used. A 20 array study using total RNA recovered from bacteria from bacteria that were either grown in human serum or Iso-Sensitest (IST) broth, with and without ciprofloxacin challenge. Arrays were performed in 5 biological replicates from each condition.Upon QC checks, certain biological repeats were excluded due to poor hybridisation results.
2016-04-01 | E-GEOD-68105 | biostudies-arrayexpress
Project description:Treatment failures of antibiotic therapy are of major concern and can be caused by a misalignment of the antibiotic susceptibility determined in vitro with the behaviour of the pathogen in the patient. The aim of this study was to investigate the transcriptomic response of the uropathogenic strain E. coli CFT073 to antibiotic treatment in blood stream infection (BSI) models in order to understand and avoid antibiotic therapy failures in urosepsis treatments. Blood stream infection models were established by growing E. coli CFT073 in pooled human blood with and without ciprofloxacin. The antibiotic challenge was introduced at mid-logarithmic phase of growth of the organism to depict a clinical scenario. The responses were quantified by comparing to the responses at a given time point without the challenge. Global gene expression profiling of these conditions was examined using commercial DNA microarrays. The organismâ??s metabolic genes appeared to be regulated differently in each medium, this indicated that the bacterial growth regulation were different between the models. Bacterial growth in human serum mainly involved regulations of amino acid synthesis/utilisation such as glycine, arginine, thiamine, regulations of fimbrial proteins and bacteriophage genes. When comparing the responses to antibiotic challenge, bacteria grown in the respective medium displayed specific responses to the antibiotic challenge which were not seen in the other media. The common functions of genes that responded to the ciprofloxacin challenge were SOS response, DNA repair, DNA replication, fimbrial genes and bacteriophage initiation. A subset of the bacteriophage genes showed similar responses between the three models. From genes that were differentially regulated, responses observed in the serum model appeared to have the highest fold changes. In this study we established new models to investigate blood stream infections. They have been used to identify previously unknown differences in the molecular response to antibiotic treatment by the uropathogenic E. coli CFT073 depending on the media. These unique responses will help to unravel the complexity of bloodstream infection and can help to improve the antibiotic therapy that is used. A 10 array study using total RNA recovered from bacteria that were grown in human whole blood, with and without ciprofloxacin challenge. Arrays were performed in 5 biological replicates from each condition.
2016-04-01 | E-GEOD-68106 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2016-04-01 | E-GEOD-68107 | biostudies-arrayexpress
Project description:Investigation in bacterial transcriptomics is widely used to investigate gene regulation, bacterial susceptibility to antibiotics, host-pathogen interactions, and pathogenesis. Transcriptomics is crucially dependent on suitable methods to isolate and detect bacterial RNA. Microfluidic approaches offer ways of creating integrated point-of-care systems, analysing a sample from preparation, RNA isolation through to detection. Critical for on-chip diagnostics to deliver on their promise is that mRNA expression is not altered through the use microfluidic sample processing. Here, we investigate the impact on the use of a microfluidic sample processing system based on hydrodynamic separation upon RNA expression of bacteria isolated from blood to prove its suitability for further microfluidic test development.
2016-04-01 | GSE68064 | GEO
Project description:The Drosophila phagocytic receptor Eater is expressed specifically in phagocytic hemocytes. It contributes to host immune defense and is required for survival of bacterial infections. Eater is involved in recognition and phagocytosis of bacteria. We used microarrays to determine whether any gene expression changes after bacterial phagocytosis are dependent on the expression of the phagocytic scavenger receptor Eater. We found transcriptional regulation in response to bacterial internalization, but no significant differences between controls and samples in which eater expression had been diminshed by RNAi eater knock down. Drosophila S2 cells, a hemocyte-derived cell line with phagocytic properties, were exposed to a mixture of Gram-positive and Gram-negative bacteria at conditions of 50% of cell binding. At different time points of synchronized phagocytosis (30, 90 and 180 minutes) total RNA was extracted and subjected to microarray analysis. We compared S2 cells in which Eater expression was decreased by RNA interference with control S2 cells exposed to irrelevant double-stranded (pBR322). Three independent experiments were performed corresponding to three biological replicates. Decreased phagocytosis due to RNAi eater knock down was controlled in all cases.
2011-08-24 | E-GEOD-31564 | biostudies-arrayexpress
Project description:Microfluidic devices provide a low-input and efficient platform for single-cell RNA-seq (scRNA-Seq). Here we present microfluidic diffusion-based RNA-seq (MID-RNA-seq) for conducting scRNA-seq with a diffusion-based reagent swapping scheme. This device incorporates cell trapping, lysis, reverse transcription and PCR amplification all in one microfluidic chamber. MID-RNA-Seq provides high data quality that is comparable to existing scRNA-seq methods while implementing a simple device design that permits multiplexing. The robustness and scalability of MID-RNA-Seq device will be important for transcriptomic studies of scarce cell samples.
2019-02-25 | GSE119271 | GEO
Project description:Brain perivascular cells have been recently identified as new mesodermal cell type of the human brain. These cells reside in the perivascular niche and were shown to have mesodermal and â to a lesser extend â tissue-specific differentiation potential. Mesenchymal stem cells (MSCs) are widely discussed for the use in cell therapy in many neurological disorders. Therefore it is of importance to better understand the âintrinsicâ MSC population of the human brain. Here we systematically characterized adult human brain-derived pericytes during in vitro expansion and differentiation and compared these cells to fetal and adult human brain-derived NSCs and adult human bone marrow derived MSCs. We found that adult human brain pericytes can be isolated from hippocampal as well as cortical white matter, are â in contrast to adult human NSCs â easily expandable in monolayer cultures and show high similarities to human bone marrow-derived MSCs both regarding surface marker expression and whole transcriptome analysis. Human brain pericytes differentiated only in negligible amounts into neuroectodermal cell types using various differentiation conditions but efficiently differentiated into mesodermal progenies. Thus bone marrow-derived MSCs resemble human brain pericytes and might be therefore very interesting for possible autologous NPC-based treatment strategies, cell therapeutic approaches of neurological diseases. For the gene expression microarray analysis we used the Affymetrix U133A chips The whole procedure was performed following the manufacturer's standard protocol (Affymetrix, Santa Clara, CA). For the data processing, normalization was calculated with the GCRMA (GC content corrected Robust Multi-array Analysis) algorithm. Data post-processing and graphics was performed with in-house developed functions in Matlab. 17 samples were analyzed fNSC, Neural Stem Cell, 2 replicates ANPC-hip, adult Neuroprogenitor - Cell Hippocampus, 3 replicates ANPC-wm, adult Neuroprogenitor Cell - White Matter, 3 replicates ABPMC-hip, adult Brain Perivascular Mesodermal Cell - Hippocampus, 3 replicates ABPMC-wm, adult Brain Perivascular Mesodermal Cell - White Matter, 3 replicates MSC, Mesenchymal Stem Cell, 3 replicates
2015-11-03 | E-GEOD-62505 | biostudies-arrayexpress
Project description:Anticipating the risk for infectious disease during space exploration and habitation is a critical factor to ensure safety, health and performance of the crewmembers. As a ubiquitous environmental organism that is occasionally part of the human flora, Pseudomonas aeruginosa could pose a health hazard for the immuno-compromised astronauts. In order to gain insights in the behavior of P. aeruginosa in spaceflight conditions, two spaceflight-analogue culture systems, i.e. the rotating wall vessel (RWV) and the random position machine (RPM), were used. Microarray analysis of P. aeruginosa PAO1 grown in the low shear modeled microgravity (LSMMG) environment of the RWV compared to the normal gravity control (NG), revealed a regulatory role for AlgU (RpoE). Specifically, P. aeruginosa cultured in LSMMG exhibited increased alginate production and up-regulation of AlgU-controlled transcripts, including those encoding stress-related proteins. This study also shows the involvement of Hfq in the LSMMG response, consistent with its previously identified role in the Salmonella LSMMG- and spaceflight response. Furthermore, cultivation in LSMMG increased heat- and oxidative stress resistance and caused a decrease in the culture oxygen transfer rate. Interestingly, the global transcriptional response of P. aeruginosa grown in the RPM was similar to that in NG. The possible role of differences in fluid mixing between the RWV and RPM is discussed, with the overall collective data favoring the RWV as the optimal model to study the LSMMG-response of suspended cells. This study represents a first step towards the identification of specific virulence mechanisms of P. aeruginosa activated in response to spaceflight-analogue conditions, and could direct future research regarding the risk assessment and prevention of Pseudomonas infections for the crew in flight and the general public. The wild type P. aeruginosa PAO1 strain (ATCC 15692) was used in this study and all cultures were grown in Lennox L Broth Base (LB) (Life Technologies) at 28 °C. An overnight shaking culture (125 r.p.m.) of P. aeruginosa in LB was washed and diluted in 0.85% NaCl solution to an OD600 of 1. This bacterial suspension was used to inoculate fresh LB medium at a final concentration of 10-4 CFU/ml. Synthecon Rotating Wall Vessel bioreactors (RWV) (50 ml or 10 ml) were filled with inoculated medium so that no headspace (i.e. no bubbles) was present. Other than for stress resistance assays, for which 10 ml capacity bioreactors were used, RWV bioreactors with a capacity of 50 ml were adopted for all experiments. Identical bioreactors were mounted in triplicate on (i) a RWV device in vertical position (LSMMG) (Cellon), (ii) a RWV device in horizontal position (NG) and (iii) the center of the inner Random Positioning Machine (RPM) frame (RG) (Fokker Space), and placed in a large humidified (70%-80% relative humidity) culture chamber, to avoid evaporation of culture medium through the gas-permeable membrane at the back of each vessel (Figure 1). A 25 r.p.m. rotation speed was adopted for the RWV cultures, while RPM-cultures were randomly rotated at 10 r.p.m. (60°/s). Bacteria were grown in the three described test conditions for 24 hours. After 24 hours of cultivation, the contents of every bioreactor was gently mixed by pipetting and divided into several aliquots. Ten millilitres of culture from each growth condition was immediately fixed with RNA Protect Reagent (Qiagen), following the manufacturer's instructions, and fixed cell pellets were frozen at -20 °C until RNA extraction. Samples were immediately exposed to different stresses.
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Project description:Sample preparation is a crucial step in bottom-up proteomics. Analytical performances of bottom-up proteomics can be improved by the miniaturization of sample preparation steps. Many microfluidic devices are proposed in the field of proteomics. But many of them are not capable of handling complex sample and do not integrate the processing and digestion steps. We propose a ChipFilter Proteolysis (CFP) microfluidic device derived from the Filter Aided Sample Preparation FASP method for the miniaturization of protein processing and digestion steps in bottom-up proteomics. The microchip has two reaction chambers of 0.6 µL volume separated by a protein filtration membrane in regenerated cellulose. Cell lysis, protein concentration and rapid chemical and enzymatic treatment can be performed in our microfluidic device. Complex proteomic samples like yeast protein extract have already been analyzed with our microchip. Compared to the traditional FASP method, our microfluidic device offers a better proteome coverage with ten times less starting material and eight times quicker protocol.
2020-04-29 | PXD018066 | Pride