Comparative modeling and molecular docking of orphan human CYP4V2 protein with fatty acid substrates: Insights into substrate specificity.

Cytochromes P450 (CYPs) are a super family of heme-containing enzymes well-known for their monooxgenase reaction. There are 57 CYP isoenzymes found in human which exhibit specific physiological functions. Thirteen members of this super family are classified as "orphan" CYP because of their unknown enzymatic functions. CYP4V2 is found to be a potential drug target for Bietti crystalline corneoretinal dystrophy (BCD). However, three-dimensional structure, the active site topology and substrate binding modes of CYP4V2 remain unclear. In this study, the three-dimensional model of CYP4V2 was constructed using the homology modeling method. Four possible fatty acid substrates namely, caprylic, lauric, myrisitc and palmitic acids were optimized and evaluated for drug likeness using Lipinski's rule of five. Further, these substrates were docked into active sites of CYP4V2 and several key residues responsible for substrate binding were identified. These findings will be helpful for the structure-based drug design and detailed characterization of the biological roles of CYP4V2.