Figure 3.

Variability of nucleotides and feedback regulation of the pyrimidine pathway

(A) Relative concentration of nucleotides in 19 conditions. Metabolite concentrations are shown as log2 fold changes that are normalized to the glucose condition with the BW25113 strain. Dots show the mean of n = 3 replicates, lines show the SD. Log2 fold changes > 1 or < −1 are indicated by the color of the respective condition. Numbers next to the metabolite show the relative SD(RSD) across 17 conditions (stationary phase conditions were not considered). Note that RSD values differ from Figure 2 because the rich medium is considered here.

(B) Same as (A) for intermediates in pyrimidine nucleotide biosynthesis. The metabolic map shows the pyrimidine pathway and allosteric feedback inhibition of carbamoyl phosphate synthetase (CarAB) by UMP. The metabolic bottleneck at orotate phosphoribosyltransferase (PyrE) is present in all conditions except the NCM3722 strain, due to a frameshift mutation in MG1655-derived E. coli (Jensen, 1993).

See Figure S7.