Evolutionary Plasticity and Innovations in Complex Metabolic Reaction Networks
Figure 4
Metabolic networks with the same phenotype can have vastly different genotypes.
(A) Distribution of maximum genotype distance between 1000 networks that are the end-points of random walks leading away from the initial (E. coli) network while preserving the metabolic phenotype. (B) Maximum genotype distances (vertical axis) between initial metabolic networks able to sustain life on a given number of carbon sources (horizontal axis) and 1000 final random viable metabolic networks. For each number of carbon sources 100 random walks of 104 mutations were carried out starting from 10 different initial networks (whiskers: 95% confidence interval). (C) The distribution of minimal genotype distance between pairs of networks with different metabolic phenotypes required to sustain life on at least one carbon source. (D) Average minimal genotype distance (the mean of the distribution in (C) as a function of the number of carbon sources. The error bars are too short to be visible in this plot.