Dawie van Niekerk

The oxidative Weimberg pathway for the five-step pentose degradation to α ketoglutarate from Caulobacter crescentus is a key route for sustainable bioconversion of lignocellulosic biomass to added-value products and biofuels. Here, we developed a novel iterative approach involving initial rate kinetics, progress curves, and enzyme cascades, with high resolution NMR analysis of intermediate dynamics, and multiple cycles of kinetic modelling analyses to construct and validate a quantitative model
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The gluconeogenic conversion of 3-phosphoglycerate via 1,3-bisphosphoglycerate to glyceraldehyde-3-phosphate was compared at 30 C and at 70 C. At 30 C it was possible to produce 1,3-bisphosphoglycerate from 3-phosphoglycerate with phosphoglycerate kinase, but at 70 C, 1,3- bisphosphoglycerate was dephosphorylated rapidly to 3-phosphoglycerate, effectively turning the phosphoglycerate kinase into a futile cycle. At both temperatures it was possible to convert 3-phosphoglycerate to glyceraldehyde
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Drug detoxification dynamics explain the postantibiotic effect

Protein abundance of AKT and ERK pathway components governs cell-type- specific regulation of proliferation

The investigation entails the construction and validation of a detailed mathematical model for glycolysis of the malaria parasite Plasmodium falciparum in the blood stage trophozoite form.

Design principles of nuclear receptor signaling: how complex networking improves signal transduction

Division of labor by dual feedback regulators controls JAK2/STAT5 signaling over broad ligand range

After the removal of the extracellular antibiotic, efflux and inhibition dynamics combine to delay the synthesis of ribosomes in a concentration-dependent manner (panel ii). Colors indicate increasing antibiotic concentration, as shown in panel ii.

SED-ML simulation
https://jjj.bio.vu.nl/models/experiments/srimani2017_fig2cii/simulate

Growth-factor deprived mCFU-E cells (5x106 cells per condition) and BaF3-EpoR cells (1x107 cells per condition) were stimulated with different Epo doses and absolute concentrations were determined for pEpoR (B), pAKT (C), ppERK (D). The scale for pS6 (E) was estimated in arbitrary units. GTP-Ras (F) and ppERK were determined upon stimulation with indicated, color-coded Epo doses. pEpoR was analyzed by immunoprecipitation followed by immunoblotting, GTP-Ras was analyzed after pulldown using a
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Transcriptional response to a sudden increase in extracellular ligand (hormone), for the six network designs of (A). The transcriptional response is taken to equal the ratio ReNrL/Retotal, i.e., the fraction of REs attaching ligand-bound NR. The ligand concentration was increased from 0 to 0.005 nM and maintained constant at the latter level. The observation that design 6 is higher than all other designs at long times is robust for parameter changes up to a factor of 3.

For all experiments, primary CFU-E cells were starved and stimulated with 5 U/ml Epo. At the indicated time points, samples were subjected to quantitative immunoblotting. Experimental data (black circles) with estimated standard errors and trajectories of the best fit (solid lines) are represented. Mass spectrometry data represent replicates of four independent experiments.

This study includes the experimental data for model validation and the model predictions of that data set.

This study includes all the experimental data, SOPs and modelling files for the individual reactions used for the model construction.

Model of glycolytic oscillations in individual yeast cells in microfluidic flow chamber

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.

Inhibition of lactate flux due to glucose transport inhibitor

SED-ML simulation: https://jjj.bio.vu.nl/models/experiments/bachmann2011/simulate

SED-ML simulation: https://jjj.bio.vu.nl/models/experiments/bachmann2011/simulate

Kinetic characterisation en mathematical modelling of HK.

Kinetic characterisation en mathematical modelling of PGI.

Kinetic characterisation en mathematical modelling of PFK.

Kinetic characterisation en mathematical modelling of ALD.

Kinetic characterisation en mathematical modelling of TPI.

Kinetic characterisation en mathematical modelling of G3PDH.

Kinetic characterisation en mathematical modelling of GAPDH.

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See 'Figure 3 legend' and 'Materials and methods - Time course experiments, cell lysis and quantitative immunoblotting' for details.

Experimental data set for the kinetic characterisation of G3PDH

Experimental data set for the kinetic characterisation of ALD

Experimental data set for the kinetic characterisation of ENO

Experimental data set for the kinetic characterisation of GAPDH

Experimental data set for the kinetic characterisation of LDH

Experimental data set for the kinetic characterisation of PGI

Experimental data set for the kinetic characterisation of HK

Experimental data set for the kinetic characterisation of PFK

Experimental data set for the kinetic characterisation of PGK

Glycolytic model for Plasmodium falciparum; open system

Mathematica notebook for the parameterisation of the glucose transport rate equation based on SEEK linked experimental data.

Glycolytic model for Plasmodium falciparum; closed system

Mathematica notebook for the parameterisation of the G3PDH rate equation based on SEEK linked experimental data.

SOP for the determination of external metabolites (Glc, Pyr, Gly, Lac) in intact trophozoite incubations, and for the determination of intracellular metabolite concentrations.

SOP for the cultivation conditions of Plasmodium falciparum, including the protocol for synchronisation.

SOP for measurement of G3PDH activity in extracts.

SOP for measurement of ALD activity in extracts.

SOP for measurement of glucose transport activity in intact trophozoites.

SOP for measurement of GAPDH activity in extracts.

SOP for measurement of ENO activity in extracts.

SOP for measurement of HK activity in extracts.

SOP for measurement of PFK activity in extracts.

SOP for measurement of LDH activity in extracts.

SOP for measurement of PGK activity in extracts.

SOP for measurement of PK activity in extracts.

SOP for measurement of PGM activity in extracts.

SOP for measurement of PGI activity in extracts.

SOP for measurement of PGM activity in extracts.

SOP for measurement of TPI activity in extracts.

SOP 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.