. 2010 Mar 2;67(14):2387–2404. doi: 10.1007/s00018-010-0307-9

Table 1.

Comparison of kinetic properties of human and mouse SR (see reaction reported in Fig. 2)

	mSR			hSR
	V_max (min⁻¹)	K_m (mM)	V_max/K_m (mM⁻¹ min⁻¹)	V_max (min⁻¹)	K_m (mM)	V_max/K_m (mM⁻¹ min⁻¹)
Racemization reaction
l-Serine	45.5 ± 0.5	3.8 ± 0.1	12.0 ± 0.4	41.5 ± 1.5	4.1 ± 0.2	10.0 ± 0.8
d-Serine	113 ± 3	14.5 ± 1.1	7.8 ± 0.6	84.9 ± 4.2	10.8 ± 0.8	7.9 ± 0.9
α,β-Elimination reaction
l-Serine	81.3 ± 0.8	4.0 ± 0.5	20.3 ± 2.6	100 ± 5.1	4.7 ± 0.4	21.2 ± 2.7
d-Serine	8.8 ± 0.3	3.2 ± 0.3	2.7 ± 0.4	7.7 ± 0.3	9.5 ± 0.6	0.81 ± 0.09
l-Serine-o-sulfate	967 ± 17	0.49 ± 0.05	1,973 ± 205	807 ± 49	0.43 ± 0.05	1,879 ± 352

For both SRs the measurements were carried out in the presence of 10 μM PLP, 1 mM MgCl₂, 5 mM DTT, and 1 mM ATP, at pH 8.0 and 37°C [32, 36]. The steady-state V _max and K _m kinetic parameters were determined according to the Michaelis–Menten equation. Values are given as means ± SEM