Table 1. Apparent Reaction Rates Estimated by Single-Exponential Fitting of the Ensemble Ternary Complex Formation Experiments Shown in Figure 2^a.

observed rates	l-α-Phe		p-Az-Phe
EF-Ts	–	+	–	+
kobs (s–1)	0.12 ± 0.002	0.31 ± 0.04	0.06 ± 0.01	0.25 ± 0.02
koff (s–1)	0.005 ± 0.001	0.06 ± 0.007	0.01 ± 0.0004	0.06 ± 0.01

^aUncertainty estimates represent SD from two experimental replicates. Single-exponential fits exhibited R² values >0.95. The l-α-Phe rates compare well with previously reported results.³⁷