TABLE 1

Kinetic data for the sulfation of racemic DHMA and HMMA by recombinant SULTs and pHLC

			Product Formation Approach			Substrate Depletion Approach
			R/S			R			S
			K_m	V_max	V_max/K_m	K_m	V_max	V_max/K_m	K_m	V_max	V_max/K_m
DHMA	SULT1A1	3-Sulfate	51 ± 6	3.3 ± 0.2	0.065
	SULT1A1	4-Sulfate	n.d.	n.d.	n.d.
	SULT1A3	3-Sulfate	0.8 ± 0.2	272 ± 17	340	0.4 ± 0.1	81 ± 17	203	0.7 ± 0.2	291 ± 45	416
	SULT1A3	4-Sulfate	0.5 ± 0.2	26 ± 2	52	0.4 ± 0.1	81 ± 17	203	0.7 ± 0.2	291 ± 45	416
	pHLC	3-Sulfate	1.3 ± 0.2	0.05 ± 0.002	0.038	1.3 ± 0.7	0.054 ± 0.003	0.042	1.0 ± 0.4	0.078 ± 0.007	0.078
	pHLC	4-Sulfate	1.6 ± 0.6	0.005 ± 0.001	0.003	1.3 ± 0.7	0.054 ± 0.003	0.042	1.0 ± 0.4	0.078 ± 0.007	0.078
HMMA	SULT1A3		0.4 ± 0.1	410 ± 45	1025	0.4 ± 0.1	176 ± 18	440	0.4 ± 0.1	151 ± 15	378
	SULT1E1		75 ± 11	27 ± 2	0.36
	pHLC		0.6 ± 0.1	0.16 ± 0.01	0.26	0.5 ± 0.1	0.040 ± 0.005	0.08	0.4 ± 0.1	0.035 ± 0.003	0.087

K_m, μM; V_max, nmol · min⁻¹ · mg⁻¹; n.d., not determined; ±, error of the calculated kinetic parameters.