Mixed metal copper(II)-nickel(II) and copper(II)-zinc(II) complexes of multihistidine peptide fragments of human prion protein

► The peptide with three histidyl residues HuPrP(84-114) can simultaneously bind two equivalents of copper(II) and one equivalent of nickel(II) ions. ► H85 and H111 were identified as the major copper(II) and H96 as the preferred nickel(II) binding sites. ► The data provide further support for the outstanding affinity of copper(II) ions towards the peptide fragments of prion protein. ► Binding of nickel(II) can significantly modify the distribution of copper(II) among the available metal binding sites.