Impact of Copper Ions on Chemistry and Biology of Prion Protein

The current state of art in the studies on Cu2+ ions interactions with mammalian and chicken prion protein (PrP) is discussed. The specificity of Cu2+ binding by tandem repeat domains of PrPs is actually well supported although themajor contradictions still exist as far as the fifth binding site is concerned. The biological relevance of Cu2+ coordination to octarepeat region of mammalian PrP seems to be generally accepted although the binding of the fifth metal ion may be just a chemical property of PrP.