Fig. 3

Enzymatic properties of GDH-G446V mutant. Effects of allosteric modulators on GDH activities in EBV-transformed lymphoblasts from control subjects with GDH-wt and patient with mutant GDH-G446V. Enzymatic assays were performed on lymphoblast homogenates using 5 mM glutamate and ADP (300–1200 μM) as allosteric activator in the absence of GTP (a). Sensitivity to different concentrations of GTP (1–100 μM) tested on 4 control subjects (2 males, 2 females) of different ages (28–52 years old) at 5 mM glutamate plus 1000 μM ADP (b). GTP dose responses conducted at different concentrations of ADP on GDH-wt cells (c) and mutant GDH-G446V cells (d). Values are means ± SD, n = 4; a, *P < 0.05 and ****P < 0.0001 versus 300 μM ADP condition of corresponding genotype, ^§§P < 0.001 versus GDH-wt of corresponding assay condition; c, d *P < 0.05 and ***P < 0.001 versus 0 μM GTP condition