Project description:Investigation of whole genome gene expression level in E. coli rpoS knock-out strain grown up to stationary phase in M9 minimal media supplemented with 0.2% glucose
Project description:Investigation of whole genome gene expression level in E. coli rpoS knock-out strain grown up to stationary phase in M9 minimal media supplemented with 0.2% glucose E. coli rpoS deletion mutant grown up to OD600nm 1.5 (stationary phase) in M9 minimal media supplemented with 0.2% glucose. The high-density oligonucleotide tiling arrays used were consisted of 371,034 oligonucleotide. Data for wild type controls are GSM389302, GSM389303, and GSM389304.
Project description:The role of rpoS gene in the formation of Escherichia coli biofilms were investigated. The gene expression was compared among E. coli MG1655 wild type strain and rpoS knock-out strain in the biofilms, the planktonic exponential phase, and the planktonic stationary phase. The analysis revealed that the wild type bilfilms (WBF) showed similar pattern of gene expression with the WT planktonic stationary phase (WS), whereas the rpoS knock-out biofilms (MBF) showed similar pattern of gene expression with the wild type planktonic exponential phase (WE). Genes involved in the energy metabolism and the flagella synthesis showed higher expression in the rpoS knock-out biofilms (MBF), but not in the wild type biofilms (WBF). Moreover, genes involved in the stress responses showed higher expression in the wild type biofilms (WBF), but not in the rpoS knock-out biofilms (MBF). Experiment Overall Design: Affymetrix E. coli antisense genome array was used to compare the gene expression among E. coli wild type and rpoS konck-out strains in the biofilms, the planktonic exponential phase, and the planktonic stationary phase. All samples were grown in MOPS minimal media with 0.2% glucose. Biofilms were grown for 72 hours on glass surface in flow cells (1x4x40 mm), and planktonic cells were grown for 8 hours (exponential phase) and 12 hours (stationary phase). Experiments were repeated 3 times, which resulted in 3 replicates of 6 different samples.
Project description:The role of rpoS gene in the formation of Escherichia coli biofilms were investigated. The gene expression was compared among E. coli MG1655 wild type strain and rpoS knock-out strain in the biofilms, the planktonic exponential phase, and the planktonic stationary phase. The analysis revealed that the wild type bilfilms (WBF) showed similar pattern of gene expression with the WT planktonic stationary phase (WS), whereas the rpoS knock-out biofilms (MBF) showed similar pattern of gene expression with the wild type planktonic exponential phase (WE). Genes involved in the energy metabolism and the flagella synthesis showed higher expression in the rpoS knock-out biofilms (MBF), but not in the wild type biofilms (WBF). Moreover, genes involved in the stress responses showed higher expression in the wild type biofilms (WBF), but not in the rpoS knock-out biofilms (MBF). Keywords: cell type comparison (biofilms vs planktonic cells, wild type vs rpoS knock-out strains)
Project description:Expression profiling of wild type and purR deletion strains of E. coli K-12 MG1655 under both M9 minimal media and addition of adenine.
Project description:The physiological role of the various nucleoid-associated proteins in bacteria and HU in particular has been addressed in a number of studies but remains so far not fully understood. In this work, a genome-wide microarray hybridization approach, combined with in vivo genetic experimentation, has been performed in order to compare and evaluate the effect of HUalpha, HUbeta and HUalphabeta on the transcription of the Escherichia coli K12 genes as a function of growth phase. The histone-like protein HU is present in the E. coli cell under three dimeric forms (HUalphabeta, HUalpha2 and HUbeta2) in a ratio that varies with growth phase. The experimental protocol is designed to handle strain genotype and growth phase as independent variables. Experiment Overall Design: We used microarrays to investigate global bacterial gene expression in five genotypes of E. coli C600: WT (JO2057), hupA (JO2081), hupB (JO2083), hupAB (JO3020) and rpoS (MW30) at three growth growth phases: exponential, transition and stationary and in three growth media: LB, M9 minimal Glucose and M9 minimal Glycerol. The most relevant experiments were carried out in duplicate: the wild type (JO2057) and the hupAB (JO3020) strains were tested in the exponential and stationary phase, in LB. Wild type and hupAB strains were also tested in single experiments at the transition phase in LB. The single hupA (JO2081) and single hupB (JO2083) mutants were tested at the three growth phases in LB. Wild type and hupAB strains were compared in single experiments both in M9 Minimal Glucose and M9 Minimal Glycerol at the exponential and stationary phase. The last chips were used to test respectively the rpoS mutant at the at the exponential and stationary phase in LB.
Project description:RpoS, an alternative sigma factor, is critical for stress response in Escherichia coli. The RpoS regulon expression has been well characterized in rich media that support fast growth and high growth yields. In contrast, though RpoS levels are high in minimal media, how RpoS functions under such conditions has not been clearly resolved. In this study, we compared the global transcriptional profiles of wild type and an rpoS mutant of E. coli grown in glucose minimal media using microarray analyses. The expression of over 200 genes was altered by loss of RpoS in exponential and stationary phases, with only 48 genes common to both conditions. The nature of the RpoS-controlled regulon in minimal media was substantially different from that expressed in rich media. Specifically, the expression of many genes encoding regulatory factors (e.g., hfq, csrA and rpoE) and genes in metabolic pathways (e.g., lysA, lysC and hisD) were regulated by RpoS in minimal media. In early exponential phase, protein levels of RpoS in minimal media were much higher than that in LB media, which may at least partly account for the observed difference in the expression of RpoS-controlled genes. Expression of genes required for flagellar function and chemotaxis was elevated in the rpoS mutant. Western blot analyses show that the flagella sigma factor FliA was expressed much higher in rpoS mutants than in WT in all phase of growth. Consistent with this, the motility of rpoS mutants was enhanced relative to WT. In conclusion, RpoS and its controlled regulators form a complex regulatory network that mediates the expression of a large regulon in minimal media. Experiment Overall Design: A precise rpoS deletion mutant of MG1655 was constructed using the red recombinase method. Wild type and rpoS mutants were inoculated in triplicate into M63 glucose (0.2%) minimal media at a starting OD of 0.0001 and grown aerobically at 37oC. Cultures were harvested at OD600= 0.3 in exponential phase and at OD600= 1.5 in stationary phase. For RNA extraction, cultures were mixed directly with a boiling lysis buffer containing SDS and EDTA followed by acidic hot phenol (65C) to minimize RNA degradation. RNA samples were hybridized to Affymetrix E. coli Antisense Genome Array according to Affymetrix's standard protocols.
Project description:Investigation of whole genome gene expression level in Klebsiella pneumoniae MGH78578 grown up to mid-exponential phase in M9 minimal media supplemented with 0.2% glucose
Project description:RpoS, an alternative sigma factor, is critical for stress response in Escherichia coli. The RpoS regulon expression has been well characterized in rich media that support fast growth and high growth yields. In contrast, though RpoS levels are high in minimal media, how RpoS functions under such conditions has not been clearly resolved. In this study, we compared the global transcriptional profiles of wild type and an rpoS mutant of E. coli grown in glucose minimal media using microarray analyses. The expression of over 200 genes was altered by loss of RpoS in exponential and stationary phases, with only 48 genes common to both conditions. The nature of the RpoS-controlled regulon in minimal media was substantially different from that expressed in rich media. Specifically, the expression of many genes encoding regulatory factors (e.g., hfq, csrA and rpoE) and genes in metabolic pathways (e.g., lysA, lysC and hisD) were regulated by RpoS in minimal media. In early exponential phase, protein levels of RpoS in minimal media were much higher than that in LB media, which may at least partly account for the observed difference in the expression of RpoS-controlled genes. Expression of genes required for flagellar function and chemotaxis was elevated in the rpoS mutant. Western blot analyses show that the flagella sigma factor FliA was expressed much higher in rpoS mutants than in WT in all phase of growth. Consistent with this, the motility of rpoS mutants was enhanced relative to WT. In conclusion, RpoS and its controlled regulators form a complex regulatory network that mediates the expression of a large regulon in minimal media.
Project description:Study of the possible existence of a replication fork trap in Vibrio cholerae. 1- FX85: EPV50(WT) grown in M9 minimal medium supplemented with 0.4 % fructose to exponential phase (0.2 OD 650 nm). 2- FX86: EPV50(WT) grown in M9 minimal medium supplemented with 0.4 % fructose to stationary phase (long overnight). 3- FX288: EGV140 (oriL3) grown in M9 minimal medium supplemented with 0.4 % fructose to exponential phase (0.2 OD 650 nm). 4- FX289:EGV140 (oriL3) grown in M9 minimal medium supplemented with 0.4 % fructose to stationary phase (long overnight). 5- FX290: EGV111 (oriR4) grown in M9 minimal medium supplemented with 0.4 % fructose to exponential phase (0.2 OD 650 nm). 6- FX291:EGV111 (oriR4) grown in M9 minimal medium supplemented with 0.4 % fructose to stationary phase (long overnight). 7- FX355:EPV50 (WT) grown in LB medium to exponential phase (0.2 OD 650nm) 8- FX356:EPV50 (WT) grown in LB medium to stationary phase (overnight) 9- FX286:EGV140 (oriL3) grown in LB medium to exponential phase (0.2 OD 650nm) 10- FX287:EGV140 (oriL3) grown in LB medium to stationary phase (overnight) 11- FX292:EGV111 (oriR4) grown in LB medium to exponential phase (0.2 OD 650nm) 12- FX49: MCH1 (WT monochromosome) grown in M9 minimal medium supplemented with 0.4 % fructose to exponential phase (0.2 OD 650 nm). 13- FX48: MCH1 (WT monochromosome) grown in M9 minimal medium supplemented with 0.4 % fructose to stationary phase (long overnight). 14- FX11: EGV369 (oriL3 monochromosome) grown in M9 minimal medium supplemented with 0.4 % fructose to exponential phase (0.2 OD 650 nm). 15- FX12: EGV366 (oriR4 monochromosome) grown in M9 minimal medium supplemented with 0.4 % fructose to exponential phase (0.2 OD 650 nm). 16- FX296 EPV50 M9 Exp 17- FX294 EPV50 M9 Stat 18-FX316 EGV140 M9 Exp 19- FX315 EGV111 M9 Exp 20-FX318 MCH1 M9 Exp 21- FX317 MCH1 M9 Stat 22- FX320 EGV369 M9 Exp 23- FX319 EGV366 M9 Exp Chromosomal DNA was extracted using the Sigma GenElute bacterial genomic DNA kit. 5 μg of DNA were used to generate a genomic library according to Illumina's protocol. The libraries and the sequencing were performed by the High-throughput Sequencing facility of the I2BC (http://www.i2bc.paris-saclay.fr/spip.php?article399〈=en,CNRS, Gif-sur-Yvette, France). Genomic DNA libraries were made with the ‘Nextera DNA library preparation kit’ (Illumina) following the manufacturer’s recommendations. Library quality was assessed on an Agilent Bioanalyzer 2100, using an Agilent High Sensitivity DNA Kit (Agilent technologies). Libraries were pooled in equimolar proportions. 75 bp single reads were generated on an Illumina MiSeq instrument, using a MiSeq Reagent kit V2 (500 cycles) (Illumina), with an expected depth of 217X. Reads were aligned on the in silico reconstituted genome of the cognate strain using BWA software. An in-lab written MATLAB-based script was used to perform marker frequency analysis. Data were normalized by dividing uniquely mapping sequence reads by the total number of reads. Enrichment of uniquely mapping sequence reads in 1 kb non-overlapping windows were calculated and plotted against the chromosomal coordinates.