Exposure of Salmonella enterica serovar Typhimurium to three humectants used in the food industry: NaCl, KCl and glycerol
Ontology highlight
ABSTRACT:
ORGANISM(S): Salmonella enterica subsp. enterica serovar Typhimurium str. SL1344
SUBMITTER: Sarah Finn
PROVIDER: E-GEOD-69857 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Transcriptional profiles of Salmonella Typhimurium str. ST4/74 air-dried onto stainless steel for 4 h was compared to an early stationary phase (ESP) culture control. Cells that had been air-dried for 4 h were then subsequently rehydrated with water for a 30 min period, after which the transcriptional profile was compared to an ESP control. Carried out using 2 biological replicates for each sample; hybridised in a two-channel hybridization against Salmonella genomic DNA as the comparator/reference.
2013-05-09 | E-GEOD-46763 | biostudies-arrayexpress
Project description:Transcriptional profiles of a chlorhexidine tolerant Salmonella Typhimurium were compared to its, chlorhexidine sensitive, isogenic progenitor isolate. RNA was extracted from mid-log phase cells from both isolates, without chlorhexidine exposure and following exposure to 1 µg/ ml of chlorhexidine for 30 minutes. Transcriptional profiles of the tolerant isolate were compared to the sensitive isolate, with and without chlorhexidine exposure. Carried out using 3 biological replicates for each sample; each sample hybridised in a two-channel hybridization against Salmonella genomic DNA as the comparator/reference
2015-06-06 | E-GEOD-59566 | biostudies-arrayexpress
Project description:Microarray technology was used to monitor the level of expression of 7,657 human genes in a set of 35 nodal peripheral T-cell lymphomas.
2007-01-30 | E-TABM-191 | biostudies-arrayexpress
Project description:Microarray technology was used to identify new predictive biomarkers in samples of clinically homogeneus patients.
2008-10-26 | E-TABM-364 | biostudies-arrayexpress
Project description:Identification of gene expression signatures associated with favourable or unfavourable treatment response and clinical outcome of Hodgkin lymphoma patients.
2006-06-01 | E-MEXP-507 | biostudies-arrayexpress
Project description:Background: Lactococcus garvieae is a bacterial pathogen that affects different animal species and human. Despite the widespread distribution and emerging clinical significance of L. garvieae in both veterinary and human medicine, there is almost a complete lack of knowledge about the genetic content of this microorganism. In the present study the genomic content of L. garvieae CECT 4531 was analyzed by bioinformatic tools and microarray-based comparative genomic hybridizations (CGH) experiments, using Lactococcus lactis subsp. lactis IL1403 and Streptococcus pneumoniae TIGR4 as reference microorganisms. Results: The combination and integration of in silico analyses and in vitro (CGH) experiments performed between the reference microorganisms allowed establishing an inter-species hybridization framework with a detection threshold based on the sequence similarity ?70%. With this threshold value, 267 genes were identified as having an analogue in L. garvieae, most of which (n = 258) have been documented for the first time in this pathogen. Most of these genes are related to ribosomal, sugar metabolism or energy conversion systems. Some identified genes could be involved in the pathogenesis of L. garvieae infections. Conclusions: In this study a comparative analysis based on microarray interspecies hybridization and the use of bioinformatic tools were used for the first time to study the genetic content of L. garvieae CECT 4531. Towards this approach, we identified 267 potentially present genes in L. garvieae CECT 4531, some of which could be involved in the pathogenesis of L. garvieae infections, such as als or mycA. These results provide the first insight into the genome content of L. garvieae. Array-based comparative genome hybridization (CGH): The L. lactis subsp. lactis IL1403 and S. pneumoniae TIGR4 microarrays used for the CGH analysis were purchased from Eurogentec (Serain, Belgium). The L. lactis microarray contains 4608 spots: 2126 duplicated ORFs, 32 negative controls and 324 empty spots. The S. pneumoniae microarray contains 4608 spots: 2087 duplicated ORFs, 224 negative controls and 210 empty spots. The CGH experiments were performed by means of competitive hybridizations using DNA of L. lactis subsp. lactis IL1403 or S. pneumoniae TIGR4, depending on the array as positive controls. DNAs to be hybridized on the same array were labelled with Cy3-dUTP and Cy5-dUTP, respectively. For each microarray hybridization reaction, aliquots (1–2 µg) of labelled genomic DNAs of reference (labelled with Cy3) and test (labelled with Cy5) strains, were mixed in 45 µl EGT hybridization solution (Eurogentec, Serain, Belgium) and denatured at 65ºC for 2 min. The hybridization mixture was then loaded onto a microarray slide, covered with a coverslip and incubated at 38ºC overnight. Following hybridization, the slides were washed in 2 X SSC, 0.5% SDS for 5 min followed by 5 min in 1 X SSC, 0.25% SDS. Finally, slides were rinsed in 0.2 X SSC and dried by centrifugation. The results presented herein represent a compilation of sixteen separate CGH experiments: L. lactis subsp. lactis IL1403 arrays (reference microorganism) were hybridized with S. pneumoniae TIGR4 (test microorganism) (n=2); S. pneumoniae TIGR4 arrays (reference microorganism) were hybridized with L. lactis subsp. lactis IL1403 (test microorganism) (n=2); L. lactis subsp. lactis IL1403 arrays (reference microorganism) were hybridized with L.garvieae CECT 4531 (test microorganism) (n=8); S. pneumoniae TIGR4 arrays (reference microorganism) were hybridized with L.garvieae CECT 4531 (test microorganism) (n=4). Data acquisition and analysis: The microarray was scanned after hybridization using a Scanarray HT microarray scanner (Perkin-Elmer). The signal intensity of the two fluors was determined using ImaGene software (BioDiscovery, El Segundo, CA, USA). Microarray data were analysed using ImaGene software, Microsoft Excel and an in-house designed and built Microsoft Access database [30]. Gene calling was based on a signal-to-noise ratio (SNR) > 3 for each spot. After CGH experiments, a gene was considered to show a positive result when it was present in at least three of the four CGH assays. In the case of the L. garvieae CECT 4531 hybridizations with L. lactis subsp. lactis IL1403 arrays, it was necessary to perform a greater number of assays (n=8) due to the poor quality of one of the array batches used. Thus, the criteria chosen to determine a positive result in this case was when the gene was present in at least five of the eight CGH assays.
2010-03-23 | E-GEOD-19005 | biostudies-arrayexpress
Project description:To determine the host response to Salmonella Typhimurium (ST) in heterophils, a whole chicken genome array was used to analyze RNA isolated from heterophils stimulated in vitro with ST (30 min, 1 h, 2 h, and 3 h) or medium control (NS). Dual-color, direct comparisons were carried between ST-stimulated and non-stimulated controls (30 min vs. NS (30M/NS), 1 h vs. NS (1HR/NS), 2 h vs. NS (2HR/NS) and 3 h vs. NS (3HR/NS)). Each comparison includes four biological replicates. There were 2791, 3744, 12947 and 12482 genes differentially expressed in the comparisons of 30M/NS, 1HR/NS, 2HR/NS and 3HR/NS, respectively (P < 0.001) , while 50, 82, 153, and 146 genes were related to immune function, respectively. More than 80% of immune-related genes overlapped between the comparisons (30M/NS vs. 1HR/NS, 1HR/NS vs. 2HR/NS, and 2HR/NS vs. 3HR/NS). These candidate genes include cytokines (e.g. Interleukin (IL) 1β, -6, -10B and -12B), chemokines (e.g. IL-8, CCL4, K60 and K203) and cluster of differentiation (CD) markers (e.g. CD44, -47 and -83). A relatively large increase in the number of differentially expressed immune-related genes was observed between 1 h and 2 h post-stimulation. The results of continuous transcriptional change provide important information to elucidate both the cellular and molecular mechanisms of ST stimulation in chickens. Dual-color, common reference comparisons were carried between ST-stimulated (30M, 1HR, 2HR and 3HR) and non-stimulated controls (NS). Four biological replicates, with dye swap labeling, were included in the comparisons of each post-stimulation time point (30M/NS, 1HR/NS, 2HR/NS and 3HR/NS). Background subtracted signal intensity were collected from 16 arrays and normalized before data analysis.
2010-04-13 | E-GEOD-14684 | biostudies-arrayexpress
Project description:In response to osmolarity, Salmonella enterica serotype Typhi (S. Typhi) regulates genes required for Vi capsular antigen expression oppositely to those required for motility and invasion. Previous studies suggest that osmoregulation of motility, invasion and capsule expression is mediated through the RcsC/RcsD/RcsB phosphorelay system. Here we performed gene expression profiling and functional studies to determine the role of TviA, an auxiliary protein of the RcsB response regulator, in controlling virulence gene expression in S. Typhi. TviA repressed expression of genes encoding flagella and the invasion associated type III secretion system (T3SS-1) through repression of the flagellar regulators flhDC and fliZ, resulting in reduced invasion and reduced expression of FliC. Both RcsB and TviA reduced expression of flhDC, but only TviA altered flhDC expression in response to osmolarity. These data suggest that the auxiliary TviA protein integrates a new regulatory input into the RcsB regulon of S. Typhi, thereby altering expression of genes encoding flagella, the Vi antigen and T3SS-1 in response to osmolarity. Gene expression profiles of the S. Typhi wild-type strain, a rcsB mutant, a (delta)tviB-vexE (tviBCDEvexABCDE) mutant, and a (delta)viaB (tviABCDEvexABCDE) mutant (lacking tviA expression) was compared. Strains were cultured in SOB broth (low salt), a condition known to induce expression of TviA and the RcsCB system. Total RNA was extracted from two independent cultures (biological replicates) of each strain. cDNA was differentially labeled with Alexa Fluor 555 and 648, respectively and competitively hybridized on S.Typhimurium arrays (PFGRC, version 4). The submitted samples are biological replicates of a competitive hybridization of cDNA from the wild-type strain (Ty2) and the rcsB mutant (SW237) (GSM395580, GSM395581) or the viaB mutant (STY2) and the tviB-vexE mutant (SW74) (GSM395582, GSM395583), respectively.
2010-05-18 | E-GEOD-15752 | biostudies-arrayexpress
Project description:DNA microarrays were used to provide a global transcriptional profile of S. typhimurium during the intracellular growth phase of infection pathogenesis following infection of macrophages.
2005-08-30 | E-MEXP-415 | biostudies-arrayexpress
Project description:SSD1 is a polymorphic locus in budding yeast with many pleiotropic effects. Our lab had previously done transcript microarray of W303a in an ssd1-d background, and here we have carried out another transcript microarray across the cell cycle in an isogenic SSD1-V background. We find that a large fraction of budding yeast transcripts is differentially expressed in these cells. Ssd1 has recently been shown to bind mRNAs in vivo, but very few of these mRNAs show significant changes in levels in the SSD1-V versus ssd1-d comparison. About 20% of cell cycle-regulated transcripts are affected by SSD1-V and most of these transcripts show sharper amplitudes of oscillation in SSD1-V cells. Many transcripts whose gene products influence longevity are also affected, the largest class of which are involved in translation. Ribosomal protein mRNAs are globally down-regulated by SSD1-V. Cells were synchronized with alpha factor and sampled every 10 min across 2 cell cycles. A total of 13 samples were analyzed. No replicates were included. cDNA of the cell cycle samples were labelled with Cy5. For Cy3 labelling, asynchronous yeast population was used.
2010-05-06 | E-GEOD-16911 | biostudies-arrayexpress