Table 2

Kinetic constants for conversions of tRA, 9cRA, and 13cRA to their corresponding 4-hydroxy-RAs catalyzed by HFLM or CYP3A7 SUPERSOMES2-a

Enzyme SourceSubstrateKmVmax2-b
μM
HFLMtRA1.272400
CYP3A7 SUPERSOMEStRA2.263000
HFLM9cRA1.752720
CYP3A7 SUPERSOMES9cRA3.103250
HFLM13cRA1.78350
CYP3A7 SUPERSOMES13cRA4.101157
  • 2-a  HFLM was a pooled sample from gestational days 96 to 109. For further experimental details, seeMaterials and Methods.

  • 2-b  Units of Vmaxare pmol/min/mg of protein for HFLM and pmol/min/nmol of CYP for CYP3A7.