Table 2. Kinetic constants with retinaldehyde isomers.

Substrate and parameter	AKR1B15	AKR1B10 a	AKR1B1 a
All-trans-retinaldehyde
Km (μM)	1 ± 0.3	0.6 ± 0.1	1.1 ± 0.1
k cat (min−1)	5.4 ± 0.5	27 ± 1	0.9 ± 0.1
k cat/Km (mM−1·min−1)	5,300 ± 1,700	45,000 ± 7,600	1,300 ± 160
9-cis-retinaldehyde
Km (μM)	0.16 ± 0.03	0.7 ± 0.1	0.4 ± 0.1
k cat (min−1)	3.8 ± 0.2	0.9 ± 0.1	0.7 ± 0.2
k cat/Km (mM−1·min−1)	25,600 ± 5,300	1,300 ± 190	1,500 ± 170

Enzymatic activity was measured by using the HPLC-based method.

^aData from [23]