. 2005 Aug 9;390(Pt 1):41–47. doi: 10.1042/BJ20042051

Table 1. IMPDH1 steady-state kinetic parameters.

Initial velocities were measured in 50 mM Tris/HCl, pH 8, 100 mM KCl and 1 mM DTT at 37 °C at various concentrations of IMP and NAD⁺. The kinetic parameters are derived by fitting the initial velocities to eqns 1 and 2, and are given as means±S.E.M. n.d., not determined.

IMPDH1	k_cat (s⁻¹)	K_m (IMP) (μM)	K_m (NAD) (μM)	K_ii (NAD) (mM)
Wild-type	1.2±0.4	17±2	70±10	2.0±0.6
R224P	1.3±0.3	7±2	56±15	1.0±0.4
D226N	0.7±0.2	12±2	50±10	4±3
V268I	0.8±0.3	11±2	46±9	4±2
A285T	0.9±0.3	n.d.	n.d.	n.d.
H1GFP	0.9±0.3	n.d.	n.d.	n.d.