Tularemia is caused by the category A biodefense agent Francisella tularensis. This bacterium is associated with diverse environments and a plethora of arthropod and mammalian hosts. How F. tularensis adapts to these different conditions, particularly the eukaryotic intracellular environment in which it replicates, is poorly understood. Here, we demonstrate that the polyamines spermine and spermidine are environmental signals that alter bacterial stimulation of host cells. Genomewide analysis sh ...[more]
Project description:In this experiment the transcriptional response of the opportunistic human pathogen Pseudomonas aeruginosa towards physiological concentrations of the major human host defense peptide LL-37 was investigated using microarrays. To this aim, three independent cultures of P. aeruginosa PAO1 were grown until mid-log phase in Mueller-Hinton broth and subsequently incubated with either sublethal LL-37 concencentrations (20 µg/ml) or without peptide for 2 h at 37 °C following RNA extraction and microarray analysis.
Project description:Chamberlains chemically defined broth medium (CDM) was inoculated with LVS and <br>incubated at 37 ºC overnight.<br>This start-up culture was used to inoculate fresh CDM (2 ml start-up culture into 25<br>ml fresh broth) and incubated at 26ºC for 24 h. Following this incubation, the optical<br>density (OD600) of this culture was recorded and RNA was extracted. For the<br>temperature shift, 5 ml of the same culture was diluted into 25 ml fresh CDM and<br>incubated at 37ºC until attaining an OD600 comparable to the 26 ºC culture (typically<br>~6 h). When the 37ºC culture reached the desired OD600, RNA was harvested.
Project description:To see the effect of sub-inhibitory concentrations of tobramycin on Pseudomonas aeruginosa grown under aerobic conditions. RNA was isolated form 4 biological repeats of P.aeruginosa grown to mid-log in cationic adjusted mueller hinton broth and 4 biological repeats of P.aeruginosa with the addition of 0.25ug/ml tobramycin in cationic adjusted mueller hinton broth. null
Project description:Temperate bacteriophages (prophages) have recently been demonstrated in Campylobacter jejuni. However, what they do there is largely unknown. In the series of studies that are the subject of these submissions we have investigated the relative expression levels of proteins in C. jejuni isolates that differ in the presence or absence of the CJIE1 prophage. At the time of the initial investigations whole genome sequence data were not available for the isolates used, though DNA microarray data indicated that the isolates were very closely related. The overall project was carried out through four separate experiments. Previous work in the scientific literature indicated that growth on medium lacking blood but containing sodium deoxycholate induced the expression of at least some proteins associated with virulence and provided data thought to be of relevance to the virulence of the bacterium. The second set of experiments (experiment 2) therefore compared protein expression in 4-plex iTRAQ experiments using two isolates. Isolate 00-2425 carried the CJIE1 prophage while the second isolate, 00-2426, did not. Three replicate experiments were done. Each isolate was grown on Mueller Hinton agar base and Mueller Hinton agar containing 0.1% sodium deoxycholate.
Project description:B. cenocepacia J2315 was grown on LB medium to mid-stationary phase at O.D. 0.5 at 150 rpm in a shaking incubator at two different temperatures: 37 degrees and 20 degrees centigrade.
Project description:Global gene expression in three clinical isolates of the ET12 lineage of Burkholderia cenocepacia was compared by microarray analysis: Strain J2315 (isolated 1989), and strains BCC1616 (HI4277) and BCC1617 (HI4283), both isolated in 2008.
Project description:B. cenocepacia J2315 was exposed to heat stress and to stress form reactive oxygen species. <br>To expose the cultures to heat stress, cells were grown at 37ºC to an O.D. of 0.4 to 0.45 and then transferred into a different shaking incubator at 42.5ºC, incubated for 1 hour at 150 rpm and harvested.<br>To expose cultures to oxidative stress by reactive oxygen species, cells were grown at 37ºC to an OD of 0.5. Then t butyl hydroperoxide or hydrogen peroxide solution were added to the culture at 0.001% and 0.15% final concentration. The culture was further incubated for 15 min and then harvested. <br>The expression profiles were compared to cells grown in LB medium without exposure to stress.<br>
Project description:B. cenocepacia J2315 was grown to mid-log phase in different media: LB broth, iso-sensitest broth, basal salt medium with glucose<br>at pH 7 and pH 6, basal salt medium at pH 7 with a reduced iron content, and basal salt medium with glycerol
Project description:B. cenocepacia J2315 was grown to mid-stationary phase in basal salt medium with two different substrates: 20 mM glucose or 40 mM glycerol. Cells were harvested after 30 hours incubation at 37 degrees centigrade. <br>The expression profile was compared to cells grown on the same medium and harvested in mid-log phase.