AFM study of the interaction of cytochrome P450 2C9 with phospholipid bilayers

Cytochromes P450 (CYP) are key enzymes involved in the metabolism of drugs and other lipophilic xenobiotics and endogenous compounds. In this study, atomic force microscopy was applied to characterise the association of CYP2C9 to dimyristoylphosphatidylcholine (DMPC) supported phospholipid bilayers. CYP2C9 was found to exclusively localise in the gel domains of partially melted DMPC bilayers. Despite lacking the N-terminus transmembrane spanning domain, the CYP2C9 protein appeared to partially embed into the membrane bilayer, as evidenced by an increase in melting temperature of surrounding phospholipids. Reversible binding of CYP2C9 via an engineered His tag to a phospholipid bilayer was facilitated using nickel-chelating lipids, presenting potential applications for biosensor technologies.