A Model Metabolic Cycle Simulated with the Mathematica Program

Víctor García-Herrero, Francisco López-Cánovas, Antonio Sillero

Departamento de Bioquímica, Facultad de Medicina, Instituto de, Investigaciones Biomédicas Alberto Sols UAM/CSIC, Madrid, Spain.

DOI: 10.4236/jbise.2014.75031                

Abstract

A system of differential equations has been used to simulate a model metabolic cycle, containing only one initial substrate and 8 irreversible enzymes. The metabolic course of the intermediates (products/substrates) was also explored in different situations: changes in the kinetic constants of one of the enzymes of the cycle; introduction of one reversible step; consecutive increments in the Km values of each enzyme of the cycle and the presence of two initial substrates. A decrease or an increase in the Km value of one of the enzymes of the cycle promotes a decrease or an increase in the steady state level of its own substrate, respectively; by the contrary, a decrease or an increase in the Vmax value promotes, respectively, an increase or a decrease in the stationary level of the corresponding substrate. A comparison between a linear and a cyclic metabolic pathway is also presented.

Keywords

Metabolic Pathways, Metabolic Cycle, Mathematical Simulations, Differential Equations

Conflicts of Interest

The authors declare no conflicts of interest.

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