Structural basis for drug and substrate specificity exhibited by FIV encoding a chimeric FIV/HIV protease.

The article presents a study that describes the crystal structures of 6s98S feline immunodeficiency virus (FIV) protease (PR) bound to darunavir (DRV) and lopinavir (LPV) and analyzes the role of the HIV residues in conferring sensitivity to DRV and LPV. The 6s-98S chimeric PR gene was augmented by PCR from the viral genome and cloned into pET21a expression vector. It concludes that the chimeric FIV PR system is used to screen for new broad-spectrum inhibitors, select mutants resistant to DRV/LPV and study the evolution pathway of resistance.