Table 1.

Binding and Deiodination of I-Tyr Zwitterionic Derivatives with IYD^a

compound	Kd (μM)b	kcat (s−1) × 10−2c	Km (μM)c	kcat/Km (M−1 s−1)
I-Tyrd	5.7 ± 0.4	60 ± 0.5	49 ± 10	(1.2 ± 0.2) × 104
I-tyrosinamide	7.0 ± 0.2	1.7 ± 0.2	2410 ± 410	5.7 ± 0.7
I-tyramine	99 ± 10	1.8 ± 0.3	1470 ± 450	13 ± 4.5
I-HPPA	>4000	<9.3 × 10−3e
I-HPLA	>3000	1.3 ± 0.1	270 ± 30	47 ± 5
D-I-Tyr	270 ± 15	2.7 ± 1.0	7900 ± 4000	3.4 ± 1

^aData represent the average of two independent measurements and the error represents their range.

^bSee Figure S1.

^cSee Figure S2.

^dFrom Kozyryev et al.²⁶

^eEstimated from the detection limit of HPPA by A₂₈₀ during HPLC analysis.