Project description:FabR ChIP-chip on Salmonella enterica subsp. enterica serovar Typhimurium SL1344 using anti-Myc antibody against strain with chromosomally 9Myc-tagged FabR (IP samples) and wildtype strain (mock IP samples)
Project description:Conjugative plasmids are the main vehicle for the horizontal spread of antimicrobial resistance (AMR). Although AMR plasmids provide advantages to their hosts under antibiotic pressure, they can also disrupt the cell’s regulatory network, impacting the fitness of their hosts. Despite the importance of plasmid-bacteria interactions on the evolution of AMR, the effects of plasmid carriage on host physiology has remained underexplored, and most studies have focused on model bacteria and plasmids that lack clinical relevance. Here, we analyzed the transcriptional response of 11 clinical enterobacterial strains (2 Escherichia coli, 1 Citrobacter freundii and 8 Klebsiella spp.) and the laboratory-adapted E. coli MG1655 to carriage of pOXA-48, one of the most widely spread carbapenem-resistance plasmids. Our analyses revealed that pOXA-48 produces variable responses on their hosts, but commonly affects processes related to metabolism, transport, response to stimulus, cellular organization and motility. More notably, the presence of pOXA-48 caused an increase in the expression of a small chromosomal operon of unknown function in Klebsiella spp. and C. freundii, which is not present in E. coli. Phylogenetic analysis suggested that this operon has been horizontally mobilized across different Proteobacteria species. We demonstrate that a pOXA-48-encoded LysR transcriptional regulator controls the expression of the operon in Klebsiella spp. and C. freundii. In summary, our results highlight a crosstalk between pOXA-48 and the chromosome of its natural hosts.
Project description:Plasmids are extrachromosomal genetic elements commonly found in bacteria. Plasmids are known to fuel bacterial evolution through horizontal gene transfer (HGT), but recent analyses indicate that they can also promote intragenomic adaptations. However, the role of plasmids as catalysts of bacterial evolution beyond HGT remains poorly explored. In this study, we investigate the impact of a widespread conjugative plasmid, pOXA-48, on the evolution of various multidrug-resistant clinical enterobacteria. Combining experimental and within-patient evolution analyses, we unveil that plasmid pOXA-48 promotes bacterial evolution through the transposition of plasmid-encoded IS1 elements. Specifically, IS1-mediated gene inactivations expedite the adaptation rate of clinical strains in vitro and foster within-patient adaptation in the gut. We decipher the mechanism underlying the plasmid-mediated surge in IS1 transposition, revealing a negative feedback loop regulated by the genomic copy number of IS1. Given the overrepresentation of IS elements in bacterial plasmids, our findings propose that plasmid-mediated IS transposition represents a crucial mechanism for swift bacterial adaptation.
Project description:We report the changes in transcriptional landscape that occur under anaerobic conditions in the absence of a DMSO reductase in Salmonella enterica subsp. enterica serovar Typhimurium strain 14028s. By comparing the transcriptome of the parental, wild-type Salmonella to the transcriptome of a ∆dmsABC strain, we identified that there was a significant upregulation of SPI-2 genes in the ∆dmsABC strain.
Project description:The deposited microarray data were generated in a study that integrated the gene expression profiles and metabolic responses of Caco2 cells incubated with Bifidobacterium infantis subsp. infantis and Salmonella enterica subsp. enterica sv. Typhimurium. The aim of this study was to investigate the interaction of B. infantis, S. Typhimurium, and host cells (Caco2) in the course of infection to understand the molecular mechanics of probiotic-pathogen-host interactions.
Project description:Transcriptional profile of Salmonella enterica sv Typhimurium SL1344 ΔSTM2239 mutant cultures containing either a plasmid control (pFLAG-CTC) or a plasmid carrying STM2239 (pFLAG-STM2239) in the presence of IPTG.
Project description:ChIP-chip analysis of DNA specifically bound to anti-σ54 from mid-exponentially growing Salmonella enterica sv Typhimurium ATCC14028 wild type and ΔrpoN mutant cultures containing plasmid pPBHP192 expressing protein DctD250
Project description:This study aimed to compare differentially expressed transcripts in Salmonella recovered from the inoculated onion bulbs using transcriptome profiling (RNA-seq). The Salmonella strains of Salmonella enterica subsp. enterica ser. Newport, isolated from clinical cases affected by the onion-linked outbreak in 2020 (CDC, 2020), was used for the onion bulb inoculation. Transcriptomic analysis of Salmonella was performed 1 day (24 hours) and 7 days post-inoculation to identify Differentially Expressed Genes (DEGs) . 925 and 736 genes were upregulated within 24 hours and seven days after inoculation, while the number of downregulated genes in the same timeframe was 690 and 826, respectively (FDR<0.05 and Abs (log 2(Y/X) >0).
Project description:Single-molecule read technologies allow for detection of epigenomic base modifications during routine sequencing by analysis of kinetic data during the reaction, including the duration between base incorporations at the elongation site (the "inter-pulse duration.") Methylome data associated with a closed de novo bacterial genome of Salmonella enterica subsp. enterica serovar Javiana str. CFSAN001992 was produced and submitted to the Gene Expression Omnibus. Single-sample sequencing and base modification detection of cultured isolate of a foodborne pathogen.