Single-Protein Tracking Reveals That NADPH Mediates the Insertion of Cytochrome P450 Reductase into a Biomimetic of the Endoplasmic Reticulum

• DOI: 10.1021/jacs.7b00663
• Publication Date: 2017-03-28T04:28:30Z
• Authors: Carlo Barnaba; Michael J. Martinez; Evan Taylor; Adam O. Barden; James A. Brozik
• Keywords: 0301 basic medicine; 0303 health sciences; 03 medical and health sciences; Biomimetic Materials; Lipid Bilayers; Humans; Endoplasmic Reticulum; Mass Spectrometry; NADP; Chromatography, Liquid; NADPH-Ferrihemoprotein Reductase

Cytochrome P450 reductase (CPR) is the redox partner for most human cytochrome enzymes. It also believed that CPR an integral membrane protein exclusively. Herein, we report that, contrary to this belief, can exist as a peripheral in absence of NADPH and will transition presence stoichiometric amounts or greater. All experiments were performed solid-supported cushioned lipid bilayer closely matched chemical composition endoplasmic reticulum served ER biomimetic. The phase characteristics fluidity biomimetic was characterized with fluorescence micrographs temperature-dependent recovery after photobleaching. interactions directly observed by tracking single molecules using time-lapse single-molecule imaging subsequent analysis tracks. These studies revealed dramatic changes diffusion coefficient degree partitioning function concentration.