Table II.

Comparison of kinetic parameters of PpBADH variants and selected other ALDHs

Variant	Km (µM)	kcat (s−1)	kcat/Km (M−1s−1)
PpBADHa,b
WT	4.4 ± 2.2	156 ± 29	3.5 × 107
E215D	28 ± 3.9 (6.4)	1.5 ± 0.2 (104)	5.4 × 104 (640)
E215Q	n.a.c	n.a.	n.a.
E215L	n.a.	n.a.	n.a.
E337D	6.6 ± 0.7 (1.5)	45 ± 1 (3.5)	6.8 × 106 (5.1)
E337Q	20 ± 1.6 (4.5)	0.8 ± 0.1 (195)	4.0 × 104 (875)
E337L	20 ± 1.5 (4.5)	1.3 ± 0.1 (120)	6.5 × 104 (540)
hALDH2d
WT	0.5	3.2	6.4 × 106
E268Q	0.6 (1.2)	6.7 × 10−4 (4800)	6.2 × 102 (10 000)
E399Q	0.3 (0.6)	0.33 (10)	1.1 × 106 (5.8)
rALDH3e
WT	0.2 ± 0.02	79	3.9 × 108
E333Q	4.2 (21)	1.6 (3.0)	3.8 × 105 (1000)
hALDH3f
WT	220	0.9	4.1 × 103
E209Q	580 (2.6)	0.8 (0.9)	1.4 × 103 (2.9)
E333Q	n.a.	n.a.	n.a.

^aReactions were carried out in TAPS buffer (0.1 M, pH 8.5) containing 0.1 M KCl, 1 mM NAD⁺ and 1 mM DTT at 30°C. Data were treated as described in Materials and methods.

^bIn parentheses is the fold increase in K_m value or decrease in k_cat or k_cat/K_m values.

^cn.a. = no enzyme activity detected within the limits of the assay.

^dData for reaction of hALDH2 with propionaldehyde from Wang and Weiner (1995) and Sheikh et al. (1997).

^eData from Hempel et al. (2001).

^fData from Mann and Weiner (1999).