Difference between revisions of "DXS"

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(Modelling DXS)
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== Modelling DXS ==
 
== Modelling DXS ==
  
In the kinetic model, the DXS reaction is modelled with reversible Michaelis-Menten using the Hanekom <ref> Hanekom2016 </ref> bi-bi random order generic equation. In total, this reaction requires six kinetic parameters and one thermodynamic parameter (Equilibrium constant, Keq).  
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In the kinetic model, the DXS reaction is modelled with reversible Michaelis-Menten using the Hanekom <ref> Hanekom2016 </ref> bi-bi random order generic equation. In total, this reaction requires five kinetic parameters (Kms for all substrates and products, and a forward Kcat) and one thermodynamic parameter (Equilibrium constant, Keq).  
  
 
<math>
 
<math>
  
V_\mathrm{DXS}= Kcat_\mathrm{forward} . [DXS]  
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V_\mathrm{DXS}= \cfrac{Kcat_\mathrm{forward} \bullet [DXS] \bullet \left( \cfrac{[Pyr]}{Km_\mathrm{DXS}} \right) \bullet \left( \cfrac{[G3P]}{Km_\mathrm{g3p}} \right) \bullet \left( 1 - \cfrac{\left( \cfrac{[DXP]\bullet[CO2]}{[Pyr]\bullet[G3P]} \right)}{K_\mathrm{eq}} \right)} {\left( 1 + \cfrac {[Pyr]}{Km_\mathrm{pyr}} + \cfrac{[CO2]}{Km_\mathrm{co2}}\right) \bullet \left( 1 + \cfrac{[G3P]}{Km_\mathrm{g3p}} + \cfrac{[DXP]}{KM_\mathrm{dxp}} \right)}
  
 
</math>
 
</math>
  
V_\mathrm{GPPS} =  Vmax_\mathrm{forward} * \cfrac { \left (\cfrac{[DMAPP]}{Km_\mathrm{DMAPP}} * \cfrac{[IPP]}{Km_\mathrm{IPP}}\right )* \left ( 1 - \cfrac {[GPP]*[PP]}{[DMAPP]*[IPP]*K_\mathrm{eq}} \right )}{\left (1 + \cfrac {[IPP]}{Km_\mathrm{IPP}} + \cfrac {[PP]}{Km_\mathrm{PP}} \right ) * \left ( 1 + \cfrac {[DMAPP]}{Km_\mathrm{DMAPP}}  + \cfrac {[GPP]}{Km_\mathrm{GPP}} \right )}
 
  
 
</math>
 
  
 
==References ==
 
==References ==
  
</references>
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<references/>
 
 
== Enzyme and Metabolite Background Information ==
 

Revision as of 13:16, 23 March 2017

You can go back to main page of the kinetic model here.


The DXS reaction (EC 2.2.1.7)


Pyruvate + G3P \rightleftharpoons DXP + CO2

Deoxyxylulose-5-phosphate synthase (DXS) catalyses the production of 1-deoxy-D-xylulose 5-phosphate (DXP) from pyruvate and glyceraldehyde 3-phosphate (G3P). This reaction is the first step in the MEP pathway.

Modelling DXS

In the kinetic model, the DXS reaction is modelled with reversible Michaelis-Menten using the Hanekom [1] bi-bi random order generic equation. In total, this reaction requires five kinetic parameters (Kms for all substrates and products, and a forward Kcat) and one thermodynamic parameter (Equilibrium constant, Keq).



V_\mathrm{DXS}= \cfrac{Kcat_\mathrm{forward} \bullet [DXS] \bullet \left( \cfrac{[Pyr]}{Km_\mathrm{DXS}} \right) \bullet \left( \cfrac{[G3P]}{Km_\mathrm{g3p}} \right) \bullet \left( 1 - \cfrac{\left( \cfrac{[DXP]\bullet[CO2]}{[Pyr]\bullet[G3P]} \right)}{K_\mathrm{eq}} \right)} {\left( 1 + \cfrac {[Pyr]}{Km_\mathrm{pyr}} + \cfrac{[CO2]}{Km_\mathrm{co2}}\right) \bullet \left( 1 + \cfrac{[G3P]}{Km_\mathrm{g3p}} + \cfrac{[DXP]}{KM_\mathrm{dxp}} \right)}


References

  1. Hanekom2016