Figure 1.

Metabolic network model. Extra- and intracellular metabolites: blue ellipses. Enzymatic reactions and transportation steps: red circles. Non-balanced compounds: within gray, round-edged rectangles. Directions of arrows reflect the direction of the steady state fluxes. System boundary: dashed line. Extra- and intracellular space: white and gray. Some links were omitted for reasons of clarity (cf. Table 1 for the complete reaction stoichiometry)