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:We report the findings of genes under the transcriptional control of Gre factors by comparing RNA-seq data from parental, wild-type Salmonella enterica enterica Typhimurium 14028s and a ∆greA ∆greB strain. By comparing differential gene expression, we identify a metabolic scheme for responding to oxidative stress that is regulated in part by the action of Gre factors
Project description:Investigation of whole genome gene expression level changes in Salmonella enterica serova Enteritidis and Typhimurium under chlorine treatment
Project description:In many Gram-negative bacteria, the stress sigma factor of RNA polymerase, σS/RpoS, remodels global gene expression to reshape the physiology of quiescent cells and ensure their survival under non-optimal growth conditions. In the foodborne pathogen Salmonella enterica serovar Typhimurium, σS is also required for biofilm formation and virulence. We have recently shown that a ΔrpoS mutation affects the magnesium content of Salmonella and expression of the primary Mg2+-transporter CorA. The other two Mg2+-transporters of Salmonella are encoded by the PhoP-activated mgtA and mgtB genes expressed under magnesium starvation, whereas the corA gene is expressed constitutively. The σS control of corA prompted us to evaluate the impact CorA in quiescent Salmonella cells, by using global and analytical proteomic analyses and physiological assays. The ΔcorA mutation conferred a competitive disadvantage to exit from stationary phase, and slightly impaired motility, but had no effect on total and free cellular magnesium contents. In contrast to the wild type strain, the ΔcorA mutant produced MgtA, but not MgtB, in the presence of high extracellular magnesium concentration. Under these conditions, MgtA production in the ΔcorA mutant did not require PhoP and, consistently, a ΔmgtA, but not a ΔphoP, mutation slightly reduced the magnesium content of the ΔcorA mutant. Nevertheless, the ΔphoP mutation strongly impaired growth and motility, in the absence of CorA only and independently of the extracellular magnesium concentration, unraveling the importance of PhoP-dependent functions in the absence of CorA. Under these conditions, several proteins involved in flagella formation, chemotaxis and secretion were affected by the ΔcorA and ΔphoP mutations in combination, but not alone. Altogether, our data pinpoint a regulatory network, where the absence of CorA is sensed and its physiological consequences alleviated by induction of MgtA- and PhoP- dependent compensatory mechanisms.
Project description:PacBio SMRT-seq of wild-type, ∆metJ, and ∆dam Salmonella enterica serovar Typhimurium grown under SPI-1-inducing and SPI-2-inducing conditions.
Project description:An RNA-seq analysis of wild-type Salmonella enterica serovar Typhimurium and ∆ydhJ isogenic mutant grown under SPI-1-inducing and SPI-2-inducing conditions.
Project description:An RNA-seq analysis of wild-type Salmonella enterica serovar Typhimurium and ∆metJ isogenic mutant grown under SPI-1-inducing and SPI-2-inducing conditions.
