. Author manuscript; available in PMC: 2008 Jul 9.

Published in final edited form as: Biochemistry. 2008 May 17;47(23):6216–6225. doi: 10.1021/bi800102x

Table 2.

Enzyme Activity of TPMT Wild-type and Mutant Proteins

mTPMT	hTPMT	Km (AdoMet) (μM)	Vmax (AdoMet) (units/mg protein)	Km (6MP) (mM)	Vmax (6MP) (units/mg protein)
WT		5.6 ± 0.5	0.96 ± 0.05	0.350 ± 0.014	0.604 ± 0.016
	WT	18.5 ± 1.7	1.59 ± 0.16	0.68 ± 0.17	1.23 ± 0.03
	Arg152Ala	25.4 ± 1.4	1.18 ± 0.06	2.73 ± 0.23	1.49 ± 0.07
	Arg152Glu	44.5 ± 3.6	0.32 ± 0.05	4.63 ± 1.75	0.51 ± 0.16
	Arg152His	23.7 ± 2.2	1.25 ± 0.10	1.43 ± 0.39	0.92 ± 0.17
	Arg226Ala	19.7 ± 2.4	1.24 ± 0.14	1.61 ± 0.11	1.59 ± 0.04
	Arg226Glu	14.8 ± 1.4	1.16 ± 0.05	1.2 ± 0.15	1.37 ± 0.06
	Arg226His	19.9 ± 2.2	1.55 ± 0.09	0.91 ± 0.13	1.26 ± 0.06
	Arg152Ala/Arg226Ala	46.3 ± 12.5	0.50 ± 0.13	6.32 ± 0.37	0.426 ± 0.014