Figure 3.

Time-course metabolic profiles of BY4742, rtg1∆ and rtg3∆ (n = 3) in (A) the TCA/glyoxylate cycle and (B) the superpathway of polyamine biosynthesis, shown together with the neighboring metabolic pathways (PPP: pentose phosphate pathway). These two pathways were the most affected by the deletion of the RTG1 and RTG3 genes. Metabolite intensities shown in the y-axis were normalized to an internal standard and relative to those of wild-type (BY4742) at time 5 h (OD₆₀₀ = 1). In S. cerevisiae, the TCA cycle occurs in the mitochondria, while the glyoxylate cycle in the peroxisome; however, both are drawn as combined in this figure, since only bulk metabolites were measured. Note that in the event of fermentative metabolism and glyoxylate cycle activation, the flow from succinate to oxaloacetate is blocked (explaining the decreased levels of fumarate, which cannot be supplemented through the anaplerotic pathway).