| Comments |
p.690 left column 4th paragraph:"However, the introduction of extra biochemical reactions into a network without the introduction of an equal number of extra compounds results in an increase of the degree of freedom of the system. To construct a metabolic network for growth on glucose and ethanol eight extra reactions + one extra net conversion rate (ethanol) were added to metabolic network, S2. With these reactions, three extra compounds were introduced (i.e., ethanol, acetaldehyde, and glyoxylate), and thus 9 - 3 = 6 extra degrees of freedom were introduced. Because the degree of freedom of network S2 with fixed values for the parameters K and d' is equal to 1, the degree of freedom of the resulting network, S5 (see Table II), for growth on glucose/ethanol mixtures is equal to 7. Because the only input variables are the consumption rates of glucose and ethanol network S5 is underdetermined." For biochemical reactions (pp.695-6) see link |