... Biochemistry , 2010, 49 (49), pp 10421–10439. DOI ... A typical reaction mixture contained 1 mM α-ketoglutarate, 250 μM NAD(P)H, 1.5 units of GDH per 100 μL of reaction volume, and different concentrations of nicotinamide in 100 mM phosphate buffer (pH 7.3) at 25 °C. The ...