Polycyclic aromatic hydrocarbons (PAHs) are a large class of chemicals in the atmosphere (6),
soil (262), waterways and oceans, and food chain (213). Some major sources of PAHs …

Chemical carcinogens are usually chemically inert and require metabolic activation by cellular
enzymes to exert their detrimental effects. A particular compound can be activated into an …

The aryl hydroxylase enzyme system is inducible in hamster fetus cell cultures. The enzyme
system is localized in the 105,000 X g pellet (" microsomal fraction"), has an absolute …

In population studies of individuals given the antihypertensive drug debrisoquine 1,3 , two
distinct phenotypes have been described: extensive metabolizers excrete 10–200 times more …

Previous kinetic studies have identified a high-affinity (S)-warfarin 7-hydroxylase present in
human liver microsomes which appears to be responsible for the termination of warfarin’s …

Immunoblotting analysis of human liver microsome preparations revealed that human
cytochrome P-450 PCN1 (hPCN1, M r ∼52,000) was expressed in each of 40 individual …

Kinetic and inhibitor studies using cDNA-expressed enzymes and human liver microsomes
have characterized the specificity of a range of cytochrome P450 (CYP) 1A substrate and …

MATERIALS AND METHODS Materials.[G-3H] Phenanthrene (specific activity= 440 mCi/mmol),[G-3H]
benz [a] anthracene (508 mCi/mmol) and metabolites trans-1, 2-, 3, 4-, 5, 6-, 8, 9-, …

Probable Mechanism of Action and Reactions Catalyzed by Monooxygenases Numerous
xenobiotics, including many chemical carcinogens, are so hydrophobic that they would remain …

Steroid hydroxylation specificities were determined for 11 forms of human cytochrome P450,
representing four gene families and eight subfamilies, that were synthesized in human …