Project description:Transcriptomic analysis in a Salmonella enterica Serovar Typhimurium SL 1344 that constitutively expresses stdE and stdF compared with a strain carrying an stdEF deletion A four chip study using total RNA recovered from two separate cultures of Salmonella enterica Serovar Typhimurium SL 1344 constitutively expressing stdE and stdF and two separate cultures of Salmonella enterica Serovar Typhimurium SL 1344 lacking stdE and stdF.
Project description:Investigation of gene expression level changes in Salmonella Typhiumurium SL1344 (R27) compared to the wild-type SL1344 strain when grown at different growth temperatures and growth phases. A 24 microarray study was performed using total RNA recovered from three separate wild-type cultures of SL1344 and three separate cultures of SL1344 (R27) grown to exponential and stationary phase at 25oC and 37oC. Each microarray measured the expression level of 4,527 genes from Salmonella Typhimurium SL1344 chromosome, 103 genes from plasmid pSLT, 100 genes from plasmid pRSF, 14 genes from plasmid pCOL1B and 207 genes from plasmid R27. Seven probes were present per transcript, with two-fold technical redundancy.
Project description:“Stress, survival and virulence: the multi-faceted host/microbial interactions.” Bacteria employ epinephrine and norepinephrine, which converge to distinct bacterial crucial processes, like survival and pathogenicity. A novel stress periplasmic membrane protein belonging to previously described BOF family, protein renamed here SrpP, and together with membrane sensor kinase QseC has an essential role in stress response and virulence of S. Typhimurium. SrpP employs its predicted binding pocket, specifically the SrpPE110 residue, and interacts with lipid A modification enzyme, LpxO dioxygenase. Upon this interaction SrpP in S. Typhimurium finely manages multiple membrane functions to culminate in survival upon stress and pathogenesis in vivo, connecting host-stress chemical signaling to cell stress in bacteria. Comparison of sensor histidine kinase qseC mutant expression levels versus wild type strain.
Project description:Investigation of whole genome gene expression level changes in a Salmonella enterica serovar Typhimurium 14028 delta GidA mutant The mutant described in this study is further analyzed in Shippy, D. C., N. M. Eakley, P. N. Bochsler, and A. A. Fadl. 2011. Biological and virulence characteristics of Salmonella enterica serovar Typhimurium following deletion of glucose-inhibited division (gidA) gene. Microb Pathog. A single chip study using three separate cultures of wild-type Salmonella enterica serovar Typhimurium 14028 and three separate cultures of a single mutant, delta GidA Salmonella enterica serovar Typhimurium 14028.
Project description:We describe how searching chimeric spectra with post-processing including MS²PIP-derived features aids the identification of hypothetical and unannotated proteins. We apply our workflow to the well-characterized human bacterial pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) and validate novel protein-coding regions with by ribo-seq translation evidence. We further elaborate how riboproteogenomics is instrumental for reannotating ORFs and the discovery of novel ORFs across bacteria.
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). A chip study using total RNA recovered from two separate wild-type cultures of Salmonella enterica serovar Typhimurium UK1 and two separate cultures of a mutant strain, Salmonella enterica serovar Typhimurium UK1 delta-iacP. Each chip measures the expression level of 4,302 genes from Salmonella enterica serovar Typhimurium.
Project description:We have investigated the role of the histone methyltransferase G9a in the establishment of silent nuclear compartments. Following conditional knockout of the G9a methyltransferase in mouse ESCs, 167 genes were significantly up-regulated, and no genes were strongly down-regulated. A partially overlapping set of 119 genes were up-regulated after differentiation of G9a-depleted cells to neural precursors. Promoters of these G9a-repressed genes were AT rich and H3K9me2 enriched but H3K4me3 depleted and were not highly DNA methylated. Representative genes were found to be close to the nuclear periphery, which was significantly enriched for G9a-dependent H3K9me2. Strikingly, although 73% of total genes were early replicating, more than 71% of G9a-repressed genes were late replicating, and a strong correlation was found between H3K9me2 and late replication. However, G9a loss did not significantly affect subnuclear position or replication timing of any non-pericentric regions of the genome, nor did it affect programmed changes in replication timing that accompany differentiation. We conclude that G9a is a gatekeeper for a specific set of genes localized within the late replicating nuclear periphery. 4 cell states each in duplicate (i.e. a total of 8 individual replicates)