Extended Data Figure 8: In the absence of serine, elevated concentrations of glycine inhibit cell growth and decrease the NADPH/NADP+ ratio.
From: Quantitative flux analysis reveals folate-dependent NADPH production
a, Schematic of serine hydroxymethyltransferase reaction. High glycine may either inhibit forward flux (product inhibition) or drive reserve flux. b, Relative cell number after culturing HEK293T cells for 3 days in regular DMEM, DMEM with no serine or DMEM with no serine and 12.5-times the normal concentration of glycine (5 mM instead of 0.4 mM). c, Relative NADPH/NADP+ ratio (normalized to cells grown in DMEM) after culturing HEK293T cell for 3 days in regular DMEM, DMEM with no serine or DMEM with no serine and 12.5-times the normal concentration of glycine. d, e, Labelling of serine and glycine after feeding [U-13C]serine or [U-13C]glycine reveals reverse serine hydroxymethyltransferase flux. Mean ± s.d., n = 3.
