. Author manuscript; available in PMC: 2017 Apr 12.

Published in final edited form as: J Am Chem Soc. 2016 Sep 27;138(40):13163–13166. doi: 10.1021/jacs.6b08458

Table 1.

Total free energies of Zn²⁺ binding (ΔG_Zn) were determined by competitive titration with Fura-2. Reported errors correspond to fitting error from a single measurement. Apparent Zn-binding enthalpies (ΔH_ITC) were determined by isothermal titration calorimetry. Reported errors are standard deviations among at least three replicate measurements. Apparent Zn-binding entropies (ΔS_ITC) were derived from the measured ΔG_Zn and ΔH_ITC values.

R1₄ Variant	Total ΔG_Zn (kJ/mol)	Total ΔH_ITC (kJ mol^-1)	Total ΔS_ITC (kJ K^-1 mol^-1)
^c96R1₄	—186 ± 2 ^a	62 ± 13	0.84 ± 0.05
^c81/c96R1₄	—183 ± 1 ^b	59 ± 1	0.82 ± 0.01
^c38/c81/c96R1₄	—164 ± 1	10 ± 0.3	0.59 ± 0.01

From Ref 24.

From Ref 25.