Editing CYP3A4 (section)

==Technology==
Due to membrane-bound CYP3A4's natural propensity to conglomerate, it has historically been difficult to study drug binding in both solution and on surfaces. Co-crystallization is difficult since the substrates tend to have a low [[Dissociation constant|K<sub>D</sub>]] (between 5–150&nbsp;μM) and low solubility in aqueous solutions.<ref name="Sev">{{cite journal | vauthors = Sevrioukova IF, Poulos TL | title = Structural and mechanistic insights into the interaction of cytochrome P4503A4 with bromoergocryptine, a type I ligand | journal = The Journal of Biological Chemistry | volume = 287 | issue = 5 | pages = 3510–7 | date = January 2012 | pmid = 22157006 | pmc = 3271004 | doi = 10.1074/jbc.M111.317081 | doi-access = free }}</ref> A successful strategy in isolating the bound enzyme is the functional stabilization of monomeric CYP3A4 on silver [[nanoparticle]]s produced from [[nanolithography|nanosphere lithography]] and analyzed via localized [[surface plasmon resonance]] spectroscopy (LSPR).<ref name="Das">{{cite journal | vauthors = Das A, Zhao J, Schatz GC, Sligar SG, Van Duyne RP | title = Screening of type I and II drug binding to human cytochrome P450-3A4 in nanodiscs by localized surface plasmon resonance spectroscopy | journal = Analytical Chemistry | volume = 81 | issue = 10 | pages = 3754–9 | date = May 2009 | pmid = 19364136 | pmc = 4757437 | doi = 10.1021/ac802612z }}</ref> These analyses can be used as a high-sensitivity assay of drug binding, and may become integral in further high-throughput assays utilized in initial drug discovery testing. In addition to LSPR, CYP3A4-Nanodisc complexes have been found helpful in other applications including [[Solid-state nuclear magnetic resonance|solid-state NMR]], redox potentiometry, and [[enzyme kinetics|steady-state enzyme kinetics]].<ref name="Das" />