Fig. 3. UV-Vis absorption and CD characterization of L_ASD(HHCC) and L_ASD(AHCC). (A) Absorption and (B) CD monitoring of Zn²⁺ titrations of L_ASD(HHCC) (19 μM, left) and L_ASD(AHCC) (14 μM, right) in phosphate buffer (20 mM, pH 7.0) containing TCEP (500 μM) with inserts showing the evolution of the absorbance at 220 nm. For absorption, the spectrum of the metal-free peptide was subtracted from each spectrum. (C) Absorption monitoring of Co²⁺ titrations of L_ASD(HHCC) (153 μM, left) and L_ASD(AHCC) (110 μM, right) in phosphate buffer (20 mM, pH 7.0) containing TCEP (500 μM) with inserts showing the evolution of the absorbance at 690 nm for L_ASD(HHCC) and 660 and 695 nm for L_ASD(AHCC).