Project description:PrfA activity was studied in L. monocytogenes strain EGD and in an isogenic prfA deletion mutant (EGDΔprfA) carrying multiple copies of the wild-type prfA or the mutant prfA* gene (strains EGDΔprfApPrfA and EGDΔprfApPrfA*) after growth in brain heart infusion (BHI), Luria-Bertani broth (LB) or a defined minimal medium (MM) supplemented either with one of the three PTS-carbohydrates, glucose, mannose and cellobiose, or the non-PTS carbon source glycerol. Low PrfA activity was observed in the wild-type EGD strain in BHI and LB with either of these carbon sources, while PrfA activity was high in minimal medium in presence of glycerol but significantly reduced in presence of cellobiose. The strains expressing the prfA and prfA* gene under the prfA promoters, P1 and P2, produced equally large amounts of PrfA protein and high PrfA activity was observed in strain EGDΔprfApPrfA* under all growth conditions. In contrast, high PrfA activity in strain EGDΔprfApPrfA was only observed when this strain was cultured in BHI but not in LB or MM (in presence of either carbon source). A ptsH mutant (lacking a functional HPr) was able to grow in BHI suggesting that growth of L. monocytogenes in this culture medium is supported by carbon sources whose uptake and metabolism are independent of the PTS pathway. However, this mutant was unable to grow in LB and MM regardless which of the four carbon sources was added, suggesting that uptake of the used carbohydrates and the catabolism of glycerol depend fully on the functional common PTS pathway. Furthermore, the growth rates of L. monocytogenes are strongly reduced in presence of large amounts of PrfA protein when growing MM but less in LB and only slightly in BHI. The expression profiles of the genes encoding PTS permeases were determined in the three strains under various growth conditions. The data suggest that PrfA activity correlates with the expression level and the phosphorylation state of specific PTS permeases. This SuperSeries is composed of the following subset Series: GSE12143: Listeria monocytogenes EGD after growth BHI vs. LB vs. MM GSE12145: Listeria monocytogenes EGDΔprfApPrfA and EGDΔprfApPrfA* compared to the wild type strain EGD GSE12146: Listeria monocytogenes EGD and EGD-e
Project description:PrfA activity was studied in L. monocytogenes strain EGD and in an isogenic prfA deletion mutant (EGDΔprfA) carrying multiple copies of the wild-type prfA or the mutant prfA* gene (strains EGDΔprfApPrfA and EGDΔprfApPrfA*) after growth in brain heart infusion (BHI), Luria-Bertani broth (LB) or a defined minimal medium (MM) supplemented either with one of the three PTS-carbohydrates, glucose, mannose and cellobiose, or the non-PTS carbon source glycerol. Low PrfA activity was observed in the wild-type EGD strain in BHI and LB with either of these carbon sources, while PrfA activity was high in minimal medium in presence of glycerol but significantly reduced in presence of cellobiose. The strains expressing the prfA and prfA* gene under the prfA promoters, P1 and P2, produced equally large amounts of PrfA protein and high PrfA activity was observed in strain EGDΔprfApPrfA* under all growth conditions. In contrast, high PrfA activity in strain EGDΔprfApPrfA was only observed when this strain was cultured in BHI but not in LB or MM (in presence of either carbon source). A ptsH mutant (lacking a functional HPr) was able to grow in BHI suggesting that growth of L. monocytogenes in this culture medium is supported by carbon sources whose uptake and metabolism are independent of the PTS pathway. However, this mutant was unable to grow in LB and MM regardless which of the four carbon sources was added, suggesting that uptake of the used carbohydrates and the catabolism of glycerol depend fully on the functional common PTS pathway. Furthermore, the growth rates of L. monocytogenes are strongly reduced in presence of large amounts of PrfA protein when growing MM but less in LB and only slightly in BHI. The expression profiles of the genes encoding PTS permeases were determined in the three strains under various growth conditions. The data suggest that PrfA activity correlates with the expression level and the phosphorylation state of specific PTS permeases. This SuperSeries is composed of the SubSeries listed below.
Project description:Investigation of whole genome gene expression level changes in Listeria monocytogenes EGD-e during incubation (0, 15 min, 30 min) in two types of soil extracts (TA, DA).
Project description:Comparison of Listeria monocytogenes transcripts in different strains (EGD wild-type versus EGD-e wild-type, EGD-e PrfA* versus EGD-e wild-type).
Project description:Comparison of Listeria monocytogenes transcripts in different strains (EGD wild-type versus EGD-e wild-type, EGD-e PrfA* versus EGD-e wild-type).
Project description:Transcriptional profile of wild type L. monocytogenes (EGDe) and a pycA mutant strain was compared on growth in BHI. The human pathogen L. monocytogenes is a facultatively intracellular bacterium that survives and replicates in the cytosol of many mammalian cells. The listerial metabolism, especially under intracellular conditions , is still poorly understood. Recent studies analyzed the carbon metabolism of L. monocytogenes by the 13C-isotopologue perturbation method in a defined minimal medium containing [U-13C6]glucose. It was shown that these bacteria produce oxaloacetate mainly by carboxylation of pyruvate due to an incomplete tricarboxylic acid cycle. Here we report that a pycA insertion mutant defective in pyruvate carboxylase (PYC) still grows, albeit at a reduced rate, in BHI medium, but is unable to multiply in a defined minimal medium with glucose or glycerol 36 as carbon source. Transcriptional profiling was performed on the pycA mutant and the wild type strain grown in BHI to get a closer insight into the effect of the pycA mutation in Listeria monocytogenes.
Project description:Transcriptional profile of prfA, the dependent genes and the PTS genes after growth in BHI (brain-heart-infusion), LB (Luria Bertani broth) and MM (minimal medium (Premaratne et al. 2001) (each supplemented with 50 mM Glucose). Keywords: media comparison
Project description:These studies were designed to examine the acute Listeria monocytogenes transcriptional response to mammalian (porcine) bile. Triplicate WT Listeria monocytogenes (strain 10403S) were grown to mid-log in BHI at 37 °C. Samples were divided, and either treated or not treated by addition of porcine bile (Sigma, to 1% final) for 30 minutes.
Project description:Transcriptional profile of wild type L. monocytogenes (EGDe) and a pycA mutant strain was compared on growth in BHI. The human pathogen L. monocytogenes is a facultatively intracellular bacterium that survives and replicates in the cytosol of many mammalian cells. The listerial metabolism, especially under intracellular conditions , is still poorly understood. Recent studies analyzed the carbon metabolism of L. monocytogenes by the 13C-isotopologue perturbation method in a defined minimal medium containing [U-13C6]glucose. It was shown that these bacteria produce oxaloacetate mainly by carboxylation of pyruvate due to an incomplete tricarboxylic acid cycle. Here we report that a pycA insertion mutant defective in pyruvate carboxylase (PYC) still grows, albeit at a reduced rate, in BHI medium, but is unable to multiply in a defined minimal medium with glucose or glycerol 36 as carbon source. Transcriptional profiling was performed on the pycA mutant and the wild type strain grown in BHI to get a closer insight into the effect of the pycA mutation in Listeria monocytogenes. RNA from the two strains were isolated after growth in BHI and and compared using whole genome oligonucleotide microarrays
Project description:Comparisons of gene expression profiles of human hepatocytes (HepG2) infected or not by the bacterium Listeria monocytogenes (strain EGD-e) for 72 hours and analysed by RNA-seq