TABLE 2.

Equilibrium and kinetic parameters for the reaction of BEC binding to WT and mutants of CYP3A4

	WT	R212A	T224A	R212A/T224A
Ksa (μm)	0.37 ± 0.02	2.3 ± 0.3	0.44 ± 0.03	2.5 ± 0.2
kfastb (s−1)	0.66 ± 0.02	0.87 ± 0.03	0.46 ± 0.03	0.56 ± 0.02
kslowc (s−1)	0.035 ± 0.002	0.034 ± 0.002	0.039 ± 0.003	0.074 ± 0.002

^a Spectroscopic dissociation constant.

^b Rate constant for ligand binding in the fast phase, determined at BEC:CYP3A4 = 5.

^c Rate constant for ligand binding in the slow phase, determined at BEC:CYP3A4 = 5.