A Toolbox Model of Evolution of Metabolic Pathways on Networks of Arbitrary Topology
Figure 4
Diagram of a new pathway added to the metabolic network of the organism.
The diagram explains different types of metabolites and reactions. Reactions (squares) in the added pathway use base substrates (yellow circles with horizontal shading) from the metabolic core of the organism (light blue area) to produce the target metabolite (the red circle). Added pathway generates intermediate products (green circles) as well as byproducts that are not further converted to the target (blue circles). Products of some reactions feed back into the metabolic core (yellow circles with vertical shading). Reactions are labeled with expansion steps at which they were added to the pathway.