Zinc is required for folding and binding of a single zinc finger to DNA

A synthetic peptide corresponding to zinc finger 31 of the Xenopus protein Xfin adopts a folded conformation in the presence of zinc. The same peptide in the absence of zinc is not folded in a stable tertiary conformation, as determined by NMR. Binding experiments have shown that the peptide binds non-specifically to DNA only in the presence of zinc. Moreover, competitive DNA binding experiments indicate interaction with 3.9 +/- 0.4 base pairs.