Assays

Experimental data for the conversion of 3PG to F6P and the gluconeogenic pathway intermediates

Genes are transcribed in polysictronic messages (pre-mRNA) that are destined for either maturation into mRNAs, or degradation. Since transcription regulation is non-existent with few exceptions, the rate of pre-mRNA processing, together with mRNA decay and translation rates, are believed to control gene expression. In this assay, 2T1 blood form trypanosomes are subject to treatment by ActinomycinD for 5 minutes, inhibiting transcription. The cells are harvested, depleted for ribosomal RNA, and ...

Mutants with a linear respiratory chain consisting of NADH Dehydrogenase II and one of the terminal oxidases cytochrom bo, cytochrome bd I or cytochrome bd II were growth in chemostats with defined oxygen supply. The amounts of biomass formed and of acetate and formate produced were determined.

Mutant strains with linear electron transport chain were grown in chemostat cultures at different defined aerobiosis levels. Expression of selected genes was determined by Real Time RT-PCR

Mutants with linear respiratory chains were grown under SUMO chemostat conditions at different defined aerobiosis levels. The ArcA phoshorylation state as determined.

TbTryS activity was measured at 37°C in the in vivo-like buffer. All substrate stock solutions were prepared in the in vivo-like buffer and the pH was adjusted to 7.0. The assays were performed in a final volume of 2 ml and contained 0.2 mM NADH, 1 mM phosphoenolpyruvate, 4 units pyruvate kinase, 4 units L-lactate dehydrogenase, 0.17 µM TbTryS, 2.1 mM ATP and varying amounts of glutathione, and spermidine.

Assay for the isolation of intact Plasmodium falciparum trophozoites from infected red blood cells and the preparation of a cell free extract that can be used for kinetic analyses.

Enzymes involved in butanediol formation from pyruvate in L. Lactis and E. faecalis were characterized with respect to their Km's for their substrates and their Vmaxes

L. lactis, E. faecalis and S. pyogenes are referred to as LAB because of the fact that in the presence of glucose lactate is produced as the main fermentation product . This metabolic pathway is relatively inefficient, since only 2 ATP are generated from one glucose molecule. All three LAB possess the genetic make up for mixed acid fermentation, a more effective way of fermentation generating 3 ATP per molecule of glucose. All three genomes reveal (at least) two genes encoding a lactate dehydrogenase ...

L. lactis, S. pyogenes and E. faecalis were grown in C-limited chemostat cultures at various pH's and dilution rates. General flux distribution, yields and other physiological factors were studied.

In this experiment we glucose-pulsed an E. faecalis cultures re-suspended in 100 mM MES buffer at pH 6.5. Samples were taken in time to study intra- and extracellular metabolites. These data are used to construct a kinetic model of the catqabolism of E. faecalis

In this experiment we glucose-pulsed an L. lactiss cultures re-suspended in 100 mM MES buffer at pH 6.5. Samples were taken in time to study intra- and extracellular metabolites. These data are used to construct a kinetic model of the catabolism of E. L. lactis

Investigation of the dynamic switch at pH values between 5.8 and 4.5 (pH 5.5, 5.3, 5.1, 4.9, 4.7 and 4.5).

Comparison of the transcriptome at steady state in acidogenesis and at steady state in solventogenesis.

Investigation of all steady state pH-values between pH 5.7 and 4.5 (pH 5.5, 5.3, 5.1, 4.9, 4.7).

Measurements of acetone, butanol, acetate, butyrate and ethanol taken during dynamic shift (pH 5.8, 5.5, 5.3, 5.1, 4.9, 4.7, 4.5) and at steady state (pH 5.7, 5.5, 5.3, 5.1, 4.9, 4.7, 4.5).

Cells were grown to mid-exponential phase (OD600nm ~0.2) in GM17 medium at 37°C (with 0.15 mM ZnSO4 where relevant) and 84 ml of culture was mixed by inverting with 8.4 ml of fixing solution (50 mM Tris pH 8.0, 100 mM NaCl, 0.5 mM EGTA, 1 mM EDTA, 30% (v/v) formaldehyde) and incubated at room temperature for 30 min. Cells were disrupted and crosslinked DNA was sheared by sonication. Antibodies coupled to magnetic beads were used to pull down cross-linked complexes. DNA was purified, amplified, ...

Artificial transcription elongation compexes are assembled in vitro using synthetic deoxy-oligonucleotides (representing template and non template DNA strands), radiolabelled RNA (representing nascent transcript) and purified RNA polymerase. After high salt wash the incorrect NTP is added and reaction is allowed to proceed for the various amounts of time. Reaction is stopped by addition of formamide-containing loading solution and the products are resolved on high-percentage denaturing polyacryamide ...

For analyzing the binding of CcpA-HPrSer46P-complexes to various cre-elements, Surface Plasmon Resonance was used. All operations were carried out on a Biacore X instrument (Biacore, Uppsala, Sweden). Biotinylated cre DNA was coupled on a Neutravidin coated chip in flowcell two, a biotinylated reference DNA in flowcell one. For visualizing only the interactions of the CcpA-HPrSer46P-complex with the cre elements, CcpA was saturated with 50µM HPrSer46P. Titrations were carried out with 5-100nM ...

E. coli MG1655 and ∆sdhC and ∆frdA isogenic mutant strains were characterized in batch growth curves aerobic and anaerobically. Optical density, glucose consumption and by-product accumulation were measured during growth.