title: Molecular modeling on inhibitor complexes and active-site dynamics of cytochrome P450 C17, a target for prostate cancer therapy.
abstract: A molecular model for the P450 enzyme cytochrome P450 C17 (CYP17) is presented based on sequence alignments of multiple template structures and homology modeling. This enzyme plays a central role in the biosynthesis of testosterone and is emerging as a major target in prostate cancer, with the recently developed inhibitor abiraterone currently in advanced clinical trials. The model is described in detail, together with its validation, by providing structural explanations to available site-directed mutagenesis data. The CYP17 molecule in this model is in the form of a triangular prism, with an edge of approximately 55 A and a thickness of approximately 37 A. It is predominantly helical, comprising 13 alpha helices interspersed by six 3(10) helices and 11 beta-sheets. Multinanosecond molecular dynamics simulations in explicit solvent have been carried out, and principal components analysis has been used to reveal the details of dynamics around the active site. Coarse-grained methods have also been used to verify low-frequency motions, which have been correlated with active-site gating. The work also describes the results of docking synthetic inhibitors, including the drug abiraterone and the natural substrate pregnenolone, in the CYP17 active site together with molecular dynamics simulations on the complexes.
authors.affiliation: CRUK Biomolecular Structure Group, The School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK.
authors.forename: Shozeb M
authors.initials: SM
authors.lastname: Haider
authors.forename: Jagdish S
authors.initials: JS
authors.lastname: Patel
authors.forename: Chetan S
authors.initials: CS
authors.lastname: Poojari
authors.forename: Stephen
authors.initials: S
authors.lastname: Neidle
mesh_terms: D000595:Amino Acid Sequence; D020134:Catalytic Domain; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D008024:Ligands; D008297:Male; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D017386:Sequence Homology, Amino Acid; D013254:Steroid 17-alpha-Hydroxylase / Q000037:antagonists & inhibitors / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D008024:Ligands; D013254:Steroid 17-alpha-Hydroxylase