Figure 2
From: Quantification of folate metabolism using transient metabolic flux analysis
Inhibition of purine synthesis. (a) Purine concentration (C pur) 8 h after plating in untreated (open bars) and MTX-treated (filled bars) cells: MCF7 (7), MDA-MB-468 (468), and MDA-MB-231 (231). (b) Pyrimidine concentrations at the same time point. (c) Fraction of unlabeled purines. (d) Estimated purine synthesis rate. (e) Estimated purine turnover rate per unit of purines. (f) Balance between the purine synthesis (f pur) and consumption (g pur = k pur C pur) rates. The white and blue bars represent the rate of purine synthesis (white, untreated; blue, MTX-treated), and the dashed black and dashed blue bars represent the rate of purines consumption (black, untreated; blue, MTX-treated). The symbol *X denotes a difference between untreated and MTX-treated with a statistical significance less than 5 × 10−X.