. Author manuscript; available in PMC: 2018 Jun 14.

Published in final edited form as: J Am Chem Soc. 2017 Jun 5;139(23):7931–7938. doi: 10.1021/jacs.7b03114

Table 1.

Thermodynamic Parameters for Metal-Binding Interactions of Peptides 1, 4, and 9 with Co²⁺ and Zn²⁺

Parameter	Peptide
	1	4	9
	Co²⁺
K_d (μM)^a	1.4 ± 0.2	2.7 ± 1.2	1.4 ± 0.5
K_d2 (μM²)^a	150 ± 30	1500 ± 1100	70 ± 40
Zn²⁺
K_d (μM)^b	2.2 ± 0.3	0.8 ± 0.1	1.7 ± 0.2
ΔG (kcal mol⁻¹)^b	−7.72 ± 0.08	−8.30 ± 0.09	−7.90 ± 0.07
ΔH (kcal mol⁻¹)^b	−13.5 ± 0.2	−9.8 ± 0.1	−11.0 ± 0.1
TΔS (kcal mol⁻¹)^b	−5.8 ± 0.2	−1.5 ± 0.1	−3.3 ± 0.1
n^b	0.81	0.8	0.78

Determined by UV-vis titration with Co²⁺; K_d and K_d2 are the dissociation constants for formation of the 1:1 and 2:1 ligand to metal complex, respectively (see SI for details).

Determined by ITC with Zn²⁺.