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220.127.116.11 Michaelis-Menten Reaction
The material type for the Michaelis-Menten reaction is Michaelis-Menten. The following parameters must be defined:
|<forward_rate>||maximum rate at saturating substrate concentration||[n/L t]|
|<Km>||substrate concentration when reaction rate is half of||[n/L ]|
|<c0>||optional minimum substrate concentration to trigger reaction||[n/L ]|
The Michaelis-Menten reaction may be used to model enzyme kinetics where the enzyme triggers the conversion of the substrate into the product . The product molar supply is given by where is the substrate concentration. The default value of is 0. This relation may be derived, with some simplifying assumptions, by applying the law of mass action to the combination of two reactions, Since the enzyme is not modeled explicitly in the Michaelis-Menten approximation to these two reactions, this reaction model is effectively equivalent to Therefore, this reaction accepts only one reactant tag <vR> and one product tag <vP>. For consistency with the formulation of this reaction, the stoichiometric coefficients should be set to , so that .
The constitutive form of the specific forward reaction rate must be selected from the list of materials given in Section 4.11.4↓.
<reaction name="enzyme kinetics" type="Michaelis-Menten"> <Vbar>0</Vbar> <vR sol="1">1</vR> <vP sol="2">1</vP> <forward_rate type="constant"> <k>1.0</k> </forward_rate> <Km>5.0</Km> </reaction>