Assays

Dynamics of macromolecules (total RNA) during glucose pulse. Glucose pulse was performed in anaerobically growing yeast Saccharomyces cerevisiae in steady state chemostat (D = 0.1 h-1) and transent concentrations of the extra- and intracellular metabolites from central carbon metabolism (e.g. glycolysis, PPP, glycerol, purines, etc) were measured.

These files show physiological measurements from the Sheffield Infors chemostat which were made during acetate calibration and also when sampling for the steady-state transcriptional profiles.

This assay involved the determination of transcriptional profiles at 0, 2, 5, 10, 15 and 20 minutes through aerobic to anaerobic gas transitions and anaerobic to aerobic gas transitions. In each case an aerobic or anaerobic steady state was created, RNA sampled (0 min) and then the gas supply changed. RNA samples were then taken from the time at which the gas supply was changed.

For anaerobic conditions 5% CO2, 95% N2 was used.

The full transcriptional dataset is available from ArrayExpress ...

The transcriptional profiles of steady state E. coli cultures at a range of aerobiosis levels were determined. Two biological replicates and two technical replicates were carried out. Microarrays were carried out in a reference style (i.e. RNA vs a gDNA reference).

This assay describes the determination of concentrations and ratio of metabolites of adenine nucleotides (NAD and NADH). These metabolites have been extracted from Escherichia coli MG1655 and isgenic mutant strains.

This assay describes the determination of concentrations and ratio of metabolites of ubiquinones (oxidised and reduced form). These metabolites have been extracted from Escherichia coli MG1655 and isgenic mutant strains.

This .csv file shows the numbers of different cytochrome molecules per cell from steady-state continuously-grown cultures at various aerobiosis levels (0%, 31%, 56%, 85% and 115% AAU).

B. subtilis was grown in SMM media with glucose as carbon source and the samples for RNA were harvested OD578nm- 1.0). The stress conditions that were applied over here are growthat 57°C, 16°C, 1.2M Nacl and 37°C(control). All the samples were analysed for transcriptome as biological triplicates.

B. subtilis was grown in M9 media with glucose as carbon source and the samples were harvested during exponential phase (OD600nm- 0.4), early stationary phase(OD600nm- 1.3), late stationary phase(OD600nm- 1.0). All the samples were analysed for transcriptome as biological triplicates.

Is cell volume affected by potassium starvation?

The volume reduction as a response to the shift of cells from a medium of high potassium to potassium free medium will be studied in mutants lacking certain membrane transporters like Trk1,2 Nha1, etc. The conditions for the experiments follow Navarrete et al. (2010). Additionally knockouts of related regulation proteins (SAP155, SAP185) will be tested. For each mutant several time points will be measured to generate time courses.

Time courses of the internal pH changes under the conditions of Navarrete et al. (2010) will be obtained. The usage of different mutants (transport systems and regulation factors) will reveal the influence and key systems of pH regulation.

To estimate the changes of internal pH, the pH-dependent variant of GFP pHluorin is expressed in cells from a multicopy plasmid, and the changes in cell fluorescence are monitored during 5 hours of incubation in YNB-F growth media without added potassium.

How does internal potassium changes (decreases) during several hours of potassium starvation. Is there a limit for internal potassium decrease? Sampling potassium content in cells during starvation The relative membrane potential will be measured according to the conditions of Navarrete et al. (2010). Various mutants will be tested for their effect. To estimate the relative changes of plasma-membrane potential, the diSC3(3) fluorescent probe was used and the changes in cell fluorescence monitored ...

Determination of protein content at several times.

The potassium content measurements of Navarrete et al. (2010) are the basis for potassium content analysis in various mutants (Nha1, Trk1, Trk2).

External concentration changes under the conditions of Navarrete et al. (2010) will be estimated from the internal concentration changes and the volume ratio of cell sample to medium.

External pH changes for the conditions of Navarrete et al. (2010) will be estimated from the internal pH changes and the volume ratio of cell sample to medium.

The potassium fluxes will be estimated from the internal and external concentration changes.

How potassium starvation regulates the parameters of rubidium (potassium) transport. Analysis of transport characteristics during the starvation process. Kinetic characteristics of rubidium transport.

Related to the internal pH changes the proton efflux will be estimated from the internal and external concentration changes.

Based on Hess et al. (2006) ammonium is suspected to be transported via Trk1,2 under potassium shortage. The ammonium concentration in the medium will be determined for several time points under the conditions of Navarrete et al. (2010).

Is it possible to see changes in the proteome after starvation in 2D- Gels? Preparation of 2D Gels of cells incubated different periods of time in the absence of potassium.

What are the main proteins identified? Spots sampling and identification by MS