A potentiometric and spectroscopic study of the proton, and copper (II) and zinc (II) complexes formed by fibrinopeptide A.

Results are reported for a potentiometric and spectroscopic (visible, CD, and EPR) study of the complexes of fibrinopeptide A (Ala-Asp-Ser-Gly-Glu-Gly-Asp-Phe-Leu-Ala-Glu-Gly-Gly-Gly-Val-Arg) with H+, Cu2+ and Zn2+. They show that the peptide forms stable complexes with Cu2+, largely as a result of the Asp2 residue, and that its coordination behavior is almost identical to that of the N-terminal tetrapeptide fragment, Ala-Asp-Ser-Gly. Hence the influence of the remaining amino acid residues on coordination to Cu2+ is insignificant.