Project description:Investigation of whole genome gene expression level changes in Salmonella enterica serova Enteritidis and Typhimurium under chlorine treatment An eighteen chip study using total RNA isolated from three separate cultures of (1) S. Enteritidis in BHI broth (2) S. Typhimurium in BHI broth (3) S. Enteritidis in BHI broth w/ 130 ppm chlorine (4) S. Typhimurium in BHI w/ 130 ppm chlorine (5) S. Enteritidis in BHI broth w/ 390 ppm (6) S. Typhimurium in BHI broth w/ 390 ppm. Each chip measures the expression level of 5,027 ORFs covering the whole genome of S. Enteritidis and S. Typhimurium.
Project description:Investigation of whole genome gene expression level changes in Salmonella enterica serova Enteritidis and Typhimurium under chlorine treatment
Project description:Effect of mutation of rfaH on gene expression in Salmonella enterica serovar Enteritidis PT4 and Salmonella enterica serovar Typhimurium 4/74
Project description:The purpose of this experiment was to identify intestinal epithelial responses to various strains of Salmonella enterica. Human intestinal organoids were infected with three serovars of Salmonella; Typhimurium, Enteritidis and Typhi, as well as type 3 secretion system -1 and -2 mutants in Typhimurium in order to identify host responses that were similar and unique to each serovar, and responses that were dependent on these secretion systems.
Project description:Humans and animals encounter a summation of exposures during their lifetime (the exposome). In recent years, the scope of the exposome has begun to include microplastics. Microplastics (MPs) have increasingly been found in locations where there could be an interaction with Salmonella enterica Typhimurium, one of the commonly isolated serovars from processed chicken. In this study, the microbiota response to a 24-hour co-exposure to Salmonella enterica Typhimurium and/or low-density polyethylene (PE) microplastics in an in vitro broiler cecal model was determined using 16S rRNA amplicon sequencing (Illumina) and untargeted metabolomics. Community sequencing results indicated that PE fiber with and without S. Typhimurium yielded a lower Firmicutes/Bacteroides ratio compared to other treatment groups, which is associated with poor gut health, and overall had greater changes to the cecal microbial community composition. However, changes in the total metabolome were primarily driven by the presence of S. Typhimurium. Additionally, the co-exposure to PE Fiber and S. Typhimurium caused greater cecal microbial community and metabolome changes than either exposure alone. Our results indicate that polymer shape is an important factor in effects resulting from exposure. It also demonstrates that microplastic-pathogen interactions cause metabolic alterations to the chicken cecal microbiome in an in vitro chicken cecal model.
Project description:Excisable Genomic Islands (EGIs) are horizontally acquired genetic elements that harbor an array of genes with diverse functions. ROD21 is an EGI found integrated in the chromosome of Salmonella enterica serovar Enteritidis (Salmonella ser. Enteritidis). While this island is known to be involved in the capacity of Salmonella ser. Enteritidis to cross the epithelial barrier and colonize sterile organs, the role for most of ROD21 genes remains unknown, and thus identification of their function is fundamental to understand the impact of this EGI on the bacterium pathogenicity. Therefore, in this work we used a bioinformatical approach to evaluate the function of ROD21-encoded genes and delve into the characterization of SEN1990, a gene encoding a putative DNA-binding protein. We characterized the predicted structure of SEN1990, finding that this protein contains a three-stranded winged helix-turn-helix (wHTH) DNA-binding domain. Additionally, we identified homologs of SEN1990 among other members of the EARL EGIs. Furthermore, we deleted SEN1990 in Salmonella ser. Enteritidis, finding no differences in the replication/maintenance of the excised ROD21, disconfirming the previous Refseq annotation of the protein. High-throughput RNA-sequencing was carried out to evaluate the effect of the SEN1990 absence on the bacterium global transcription. We found a downregulated expression of oafB, an SPI-17-encoded acetyltransferase involved in O-antigen modification, which was restored when the deletion of SEN1990 was complemented. Our findings suggests that SEN1990 encodes a wHTH domain-containing transcriptional activator that modulates the transcription of oafB from the SPI-17, suggesting a crosstalk between these pathogenicity islands and a possible new role of ROD21 in the pathogenesis of Salmonella ser. Enteritidis.
Project description:Salmonella enterica subsp. enterica contains more than 2,600 serovars of which four are of major medical relevance for humans. While the typhoidal serovars (Typhi and Paratyphi A) are human-restricted and cause enteric fever, non-typhoidal Salmonella serovars (Typhimurium and Enteritidis) have a broad host range and predominantly cause gastroenteritis. In this study, we compared the core proteomes of Salmonella Typhi, Paratyphi A, Typhimurium and Enteritidis using contemporary proteomics. Five isolates, covering different geographical origins, and one reference strain per serovar were grown in vitro to the exponential phase. Protein levels of orthologous proteins between serovars were compared and subjected to gene ontology term enrichment and inferred regulatory interactions. Differential expression of the core proteomes of the typhoidal serovars appears mainly related to cell surface components and, for the non-typhoidal serovars, to pathogenicity. Our findings may guide future development of novel diagnostics and vaccines, and understanding of disease progression.
Project description:Investigation of whole genome gene expression level changes in a Salmonella enterica serovar Typhimurium UK1 delta-iacP mutant, compared to the wild-type strain. IacP is resoponsible for the secretion of virulence effector proteins via the type III secretion system, thereby contributing the virulence of S. Typhimurium. The mutants analyzed in this study are further described in Kim et al. 2011. Role of Salmonella Pathogenicity Island 1 Protein IacP in Salmonella enterica Serovar Typhimurium Pathogenesis. Infection and Immunity 79(4):1440-1450 (PMID 21263021).
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)
