Table 2

Effects of selective inhibitors on HLMS-catalyzed conversion of t-ROH to t-RAL

Inhibitor (10 μM)Inhibition Selectivity% Control2-a
ANFFamily 165 ± 7.8
Furafylline2-b CYP1A225 ± 5.7
DDCCYP2A6, CYP2E1124 ± 16
Orphenadrine2-b CYP2B6102 ± 4
QuercetinCYP2C875 ± 5.3
SulfaphenazoleCYP2C958 ± 2.4
TranylcypromineCYP2C1960 ± 1.2
QuinidineCYP2D665 ± 3.7
TAO2-b CYP3A subfamily30 ± 1.5

t -ROH (35 μM) was preincubated with HLMS (0.25 mg) plus inhibitors (10 μM) in potassium phosphate buffer (0.1 M, pH 7.4) at 37°C for 3 min in the dark. Reactions were initiated by addition of NADPH (1 mM) and continued for 20 min. Results are means ± S.D. of three to four measurements. Statistical differences between control and control plus inhibitor were evaluated with t tests (P < .05). For more details, see Materials and Methods.

  • ↵2-a Specific activity for control was 35.7 ± 2.7 pmol/min/mg protein.

  • ↵2-b Mechanism-based inhibitors and preincubation with HLMS plus NADPH was required.