1 ns are necessary to confer specificity for S-mephenytoin.

2  barbiturates, and the prototype substrate S-mephenytoin.

3  proteins required to convert CYP2C9 to an S-mephenytoin 4'-hydroxylase (6% of the activity of wild-t

4 ree amino acids did not confer significant S-mephenytoin 4'-hydroxylase activity to P450 2C9, althoug

5 he N-terminal portion of helix I conferred S-mephenytoin 4'-hydroxylation activity with a K(M) simila

6 286N, V292A, and F295L, were essential for S-mephenytoin 4'-hydroxylation activity.

7 ining the specificity of human CYP2C19 for S-mephenytoin 4'-hydroxylation, we constructed chimeras by

8 so failed to stimulate CYP2C19-catalyzed (S)-mephenytoin 4-hydroxylation, whereas the E48G/E49G doubl

9  2C19 is selective for 4'-hydroxylation of S-mephenytoin and 5-hydroxylation of omeprazole, while the

10  activity was assessed using the probe drugs mephenytoin (CYP-2C19), chlorzoxazone (CYP-2E1), dapsone

11 egard to inhibition of CYP2C19-catalyzed (S)-mephenytoin hydroxylation in human liver microsomes.

12                            Chlorzoxazone and mephenytoin metabolism correlated with the multiple orga

13                                              Mephenytoin metabolism was profoundly suppressed after i

14 9 is selective for the 4'-hydroxylation of S-mephenytoin while the highly similar CYP2C9 has little a