The expression profiles analysis of a virulence plasmid-cured strain of shigella flexneri
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ABSTRACT: In this study, we analyzed the expression profiles of a virulence plasmid-cured strain and wild-type strain of shigella flexneri. The results showed that the genes of glp regulon were upregulated in mutant bacteria in stationary phase cultures. The two strains were cultured in LB broth into log-phase and stationary phase respectively. Then, the total RNAs were extracted and analyzed by Nimblegen biochips.
Project description:To find the alterations of expression profiles of shigella flexneri, we performed DNA chip analysis and proteomic analysis at the same time. an overnight culture of the wild-type strain in LB broth was harvested and resuspended in 20 ml PBS buffer and then incubated in PBS at 37 degree and in rabbit ileum for 4 hours respectively.
Project description:Glyceraldehyde-3-phopshate dehydrogenase (GAPDH) is well-known for its involvement in numerous non-metabolic processes inside the mammalian cells. Alternative functions of prokaryotic GAPDH are mainly deduced from its extracellular localization and the ability to bind to selected host proteins. Data on its participation in intracellular bacterial processes are scarce as there is so far only one study dealing with this issue. We previously reported several evidence that the GAPDH homologue of Francisella tularensis, GapA, might also exert additional non-enzymatic functions. To follow up our former observation, here we decided to find out GapA’s interacting partners within the bacterial proteome to explore its new roles at the intracellular level. The quantitative proteomics approach based on stable isotope labelling of amino acids in cell culture (SILAC) in combination with affinity purification and mass spectrometry enabled us to identify 18 proteins potentially interacting with GapA, six of those interactions were further confirmed by alternative methods. Half of the identified proteins were involved in non-metabolic processes. Further analysis together with the quantitative label-free comparative analysis of proteomes isolated from the wild-type strain and strain with deleted gapA gene suggests that the GapA is implicated in DNA repair processes. The absence of GapA promotes secretion of its most potent interaction partner, the hypothetical protein with peptidase propeptide domain (PepSY) indicating its impact on subcellular distribution of some proteins.
Project description:Transcriptional profiling of E.coli SE15 comparing wild type E.coli SE15 with Autoindecur 2 synthesis gene LuxS mutnat E.coli SE15. E.coli SE15 is isolated from indwelling catheter of urinary tract infected patient. Examine change of quorum sensing related gene by deleting autoinducer 2 synthesis gene LuxS in E.coli One array: Wild type E.coli SE15 vs. LuxS mutant E.coli SE15
Project description:Label-free quantification comparative proteomics analysis of proteins secreted to the media by the T6SS of Aeromonas jandaei DSM 7311
Project description:Illumina TruSeq stranded mRNA RNA-seq including Illumina ribezeo rRNA depletion of Mycobacterium smegmatis wild type and deletion mutant of the redox-sensing MarR-type repressor HypS in three bilogical replicates prior and after 30 min after exposure to 500 µM NaOCl stress revealed that hypS is autoregulated and represses transcription of the co-transcribed hypO gene which encodes a multidrug efflux pump. DNA binding activity of HypS to the 8-5-8 bp inverted repeat sequence upstream of the hypSO operon was inhibited under NaOCl stress. HypS was identified as a novel redox-sensitive repressor that contributes to mycobacterial resistance towards HOCl stress and antibiotics.
Project description:Salmonella enterica Serovar Typhimurium (S. Typhimurium) causes enterocolitis in humans and calves characterized by diarrhea and polymorphonuclear cell (PMN) influx to the intestinal mucosa. The Salmonella Type III Secretion System encoded at Pathogenicity Island I (SPI-1) translocates the Salmonella effector proteins SipA, SopA, SopB, SopD, and SopE2 into the host epithelial cell cytoplasm. These five effector proteins act in concert to induce fluid secretion and transcription of C-X-C chemokines, which serve to recruit PMNs to the intestine. While the individual molecular interactions of these Salmonella proteins with cultured host cells have been extensively characterized, their combined role in the generation of fluid secretion and inflammation is less well understood. A bovine ligated ileal loop model was used in conjunction with a custom bovine microarray to determine intestinal response to acute S. Typhimurium infection in the calf. Gene expression responses to both wild type S. Typhimurium a delta sipA, sopABDE2 mutant were measured at seven times during the initial 12 hours of infection. Microarray analysis confirmed increased expression of genes encoding proteins previously associated with immune response to Salmonella spp. infection. Gene expression changes were mapped to molecular interaction pathways and changes in expression of mechanistic genes, which are defined as perturbed genes identified by Bayesian genetic network modeling, were strongly involved in the mechanisms of the host immune response. In addition to correctly identifying known effects of wild type S. Typhimurium on host (bovine) gene expression, Bayesian genetic network modeling identified novel effects of S. Typhimurium on several molecular interaction pathways. Novel effects impacted gene regulation in the following pathways: adipocytokine signaling, insulin signaling, complement and coagulation cascades, axon guidance, gap junction, neuroactive ligand-receptor interaction, long-term depression, long-term potentiation, melanogenesis, and natural killer cell mediated cytotoxicity. Known effects were observed in the following pathways: regulation of actin cytoskeleton, apoptosis, cytokine-cytokine receptor interaction, cell adhesion molecules (CAMs), MAPK signaling, calcium signaling, Jak-STAT signaling, leukocyte transendothelial migration, adherens junction, tight junction, and ECM-receptor interactions, phosphatidylinositol signaling system, and antigen processing and presentation. Quantitative real-time PCR was used to verify the expression of some of these mechanistic genes. Microarrays were used to examine the transcriptional profiles of bovine intestinal epithelia infected with wild type Salmonella enterica serotype Typhimurium (control and wild type or delta sipA sopABDE2 mutant infected) across seven time points (15 min, 30 min, 1, 2, 4, 8, and 12 hours). Experiments were performed in quadruplicate (bovine ligated ileal loops surgeries were performed with four calves), generateing a total of 84 arrays.
Project description:RNAseq of coding RNA in Bacillus subtilis wildtype and deletion strain GP1971 genotype trpC2 ΔcspB::cat ΔcspD::aphA3 using rRNA depleted mRNA and Illumina TruSeq stranded mRNA libraries, sequenced on Illumina MiSeq system with 2 x 75nt in paired end mode shows that the lack of the cold shock proteins CspB and CspD affects the expression of about 20% of all genes and an increased read-through at transcription terminators suggesting that CspB and CspD might be involved in the control of transcription termination.
Project description:Drugs targeting DNA and RNA in mammalian cells or viruses can also affect bacteria present in the host and thereby induce the bacterial SOS system. This has the potential to increase mutagenesis and the development of antimicrobial resistance (AMR). Here we have examined nucleoside analogues (NAs) commonly used in anti-viral and anti-cancer therapies for potential effects on mutagenesis in Escherichia coli using the Rifampicin mutagenicity assay. To further explore the mode of action of the NAs, we appliedanalyzed metabolome and proteome of E.coli deletion mutants., and metabolome and proteome analyses. Five out of the thirteen NAs examined, including three nucleoside reverse transcriptase inhibitors (NRTIs) and two anti-cancer drugs, increased the mutation frequency in E. coli more than 25-fold at doses that were within reported plasma concentration range (Pl.CR), but that did not affect bacterial growth. We show that the SOS response is induced and that the increase in mutation frequency is mediated by the TLS polymerase Pol V. Quantitative mass spectrometry based metabolite profiling did not reveal large changes in nucleoside phosphate or other central carbon metabolite pools, which suggests that the SOS induction is an effect of increased replicative stress. Our results suggest that NAs/NRTIs can contribute to the development of AMR.
Project description:New tools for studying bacterial transcripts at the single nucleotide level offer an unparalleled opportunity to understand the bacterial transcriptome. For the model pathogen Salmonella enterica serovar Typhimurium, it is necessary to identify the regulatory inputs for all RNA transcripts, including small RNAs (sRNAs) and coding genes. Here, we use RNA-seq to define the transcriptomes of mutants lacking 18 global regulatory systems that, among other functions, modulate the expression of the SPI1 and SPI2 Type Three secretion systems in S. Typhimurium strain 4/74. We directly compared the roles of the major regulators of transcription, and reported the effects of the regulatory mutations on expression of sRNAs. We also use this method to describe the impact of the RNA chaperone Hfq upon the steady state levels of 280 sRNA transcripts. Transcriptome analysis of S. Typhimurium 4/74 using RNA isolated wild-type and mutants grown under infection-relevant conditions.