Figure 2.

Zinc binding by AztC and AztD mutants. Intensity change of MF2 at 330 nm with increasing zinc in the absence (solid circles) and presence (empty circles) of apo H138/204A AztC (A) and ΔN-terminal motif (NTM) AztD (B). (C) Fluorescence emission spectra of H138/204A AztC (λ_exc = 278 nm) and (D) magnitude of the fluorescence intensity change with increasing zinc concentration. Titrations containing protein were performed in triplicate and error bars represent the standard deviation between measurements. Least squared fits are shown as solid lines for (A) and (B) and a dotted line for the linear fit in (D) with slope and R² values indicated.