Project description:The stationary phase stress response transcriptome of the human bacterial pathogen Listeria monocytogenes was defined using RNA sequencing (RNA-Seq) with the Illumina Genome Analyzer. Specifically, bacterial transcriptomes were compared between stationary phase cells of L. monocytogenes 10403S and an otherwise isogenic DsigB mutant, which does not express the alternative sigma factor σB, a major regulator of genes contributing to stress response. Keywords: Transcriptome and differential expression analyses
Project description:Listeria monocytogenes (Lm) kills up to 60% of infected newborns and adults >60 years of age but is asymptomic is most young adults. Monocytes are central to effective host defense against Lm. We hypothesize that age-dependent, pathway-specific differences in the ability of the monocyte to respond to Lm explain the increased risk of the newborn and older adult to severely suffer or die from Lm infection. To delineate age-dependent differences in innate responses that lead to differential infectious outcome, monocytes were isolated from cord blood (newborn) and peripheral blood (young and older adults) and infected with Lm. RNA was collected to determine age-dependent transcriptomic changes upon infection. Total RNA was isolated from purified human monocytes from 6 adult, 6 cord , 6 older adult blood donors that were infected with wild-type Listeria monocytogenes at a multiplicity of infected (MOI)=5 for 2 and 6 hr.
Project description:Listeria monocytogenes (Lm) kills up to 60% of infected newborns and adults >60 years of age but is asymptomic is most young adults. Monocytes are central to effective host defense against Lm. We hypothesize that age-dependent, pathway-specific differences in the ability of the monocyte to respond to Lm explain the increased risk of the newborn and older adult to severely suffer or die from Lm infection. To delineate age-dependent differences in innate responses that lead to differential infectious outcome, monocytes were isolated from cord blood (newborn) and peripheral blood (young and older adults) and infected with Lm. RNA was collected to determine age-dependent transcriptomic changes upon infection.
Project description:The foodborne pathogen Listeria monocytogenes uses a number of transcriptional regulators, including the negative regulator CtsR, to control gene expression under different environmental conditions and in response to stress. Gene expression patterns of DctsR log phase cells were compared to both wt and ictsR-mcsA log phase cells grown with 0.5mM IPTG to identify CtsR-dependent genes.We identified 62 CtsR-dependent genes that showed significant expression ratios (adj. P < 0.05), with ≥ 1.5-fold differential expression either between ΔctsR and wt or between ΔctsR and ictsR-mcsA. Keywords: Listeria monocytogenes, CtsR regulon, log phase
Project description:The foodborne pathogen Listeria monocytogenes uses a number of transcriptional regulators, including the negative regulator HrcA, to control gene expression under different environmental conditions and in response to stress. Gene expression patterns of DhrcA stationary phase cells were compared to wt to identify hrcA-dependent genes. We identified 61 HrcA-dependent genes that showed significant expression ratios (adj. P < 0.05), with ≥ 1.5-fold differential expression between ΔhrcA and wt. Combined with microarray analysis, Hidden Markov Model searches show HrcA directly repress at least 8 genes. Keywords: Listeria monocytogenes, HrcA regulon, stationary phase