TABLE 1.

Enzyme kinetic parameters of purified recombinant human ALDH1 and ALDH2

Dehydrogenase and esterase activities were determined photometrically in the presence of increasing concentrations of acetaldehyde and p-nitrophenyl acetate, respectively, as described under “Experimental Procedures.” Data are mean values ± S.E. of the parameters determined for three different enzyme preparations.

	Dehydrogenase activity		Esterase activity
	Km	Vmax	Km	Vmax
	μm	nmol × min-1 × mg-1	μm	nmol × min-1 × mg-1
ALDH1	200 ± 14	1,060 ± 20	0.69 ± 0.03	155 ± 4
ALDH2	0.33 ± 0.005	4,000 ± 30	0.18 ± 0.01	210 ± 9