A) Fluorescence spectra of PICUP samples corresponding to NAcαS-CuI (yellow), NAcαS-FeII (green), and NAcαS-FeII followed by immediate addition of CuI (purple). B) SDS-PAGE gel (left) and corresponding anti-dityrosine western blot (right) of PICUP samples of NAcαS and metal combinations involving CuI and/or FeII. C) Fluorescence spectra of PICUP samples corresponding metal bound NAcαS; control NAcαS in the absence of metals (black), NAcαS-CuII (blue), NAcαS-FeII (green), and NAcαS-FeII followed by immediate addition of CuII (orange). D) SDS-PAGE gel (left) and corresponding anti-dityrosine western blot (right) of PICUP samples of NAcαS and metal combinations involving CuII and/or FeII.