TABLE 1

Kinetic constants for DAUN reduction by recombinant AKR1A1 wild-type and variant allele proteins Values correspond to mean ± S.D. obtained from three experiments performed with three independent protein preparations (n = 9) for each isoform.


Kinetic Parameter

AKR1A1
Wild type
N52S
E55D
Km (mM) 1.2 ± 0.3 2.3 ± 0.9* 2.3 ± 1.1*
Vmax (μmol/min · mg protein) 4.4 ± 0.5 4.3 ± 2.0 3.1 ± 1.0
kcat (s–1)a 3.0 2.1 3.0
kcat/Km (s–1 M–1)
2.5 × 103
9.3 × 102
1.3 × 103
  • * Significantly different from wild type (P < 0.05)

  • a kcat calculated from Mr 41,000