TABLE 3.

Michaelis-Menten kinetics for Ycf1p transport of [³H]E₂β17G

Vacuole type	Km,appa	Vmaxa	Vmax/Km,app	Relative efficiencyb
	μm	nmol/10 min/mg
Ycf1p	394	260	0.66	1.0
Ycf1p-S251A	187	246	1.32	2.0
Ycf1p-S251E	481	276	0.57	0.86
Ycf1p-S908A, T911A	548	154	0.28	0.42

^aValues are extrapolated from Fig. 3B

^bRelative efficiency is calculated as (V_max/K_m,app of mutant)/(V_max/K_m,app of WT)