Structural Modelling of the Human Drug-Metabolizing Cytochromes P450

The structural and functional aspects of cytochrome P450 (CYP) enzymes are reviewed in the light of current developments in X-ray crystallography and other physical evidence, together with recent findings on the regulation of, and polymorphisms in, the human drug-metabolizing CYPs. It is emphasized that the crystal structures of eukaryotic CYPs are particuarly useful for constructing homology models of the human enzymes associated with drug metabolism, and that these models can aid in the high-throughput screening of novel compounds destined for human exposure.