Macromolecularization of a tripeptide analog of the Cu(II) binding site of human serum albumin. I. Synthesis, conformation, and binding properties of a Gly-Gly-His derivative of poly(L-lysine)

✍ Scribed by L. Michielin; S. Mammi; E. Peggion

• Publisher: Wiley (John Wiley & Sons)
• Year: 1983
• Tongue: English
• Weight: 227 KB
• Volume: 22
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360221102

✦ Synopsis

The Cu(I1) binding site of human serum albumin is located on the N-terminal sequence Asp-Ala-His.l-4 It has been shown that the synthetic tripeptide Asp-Ala-His N-methylamide exhibits an affinity towards Cu(I1) ions even higher than that of serum albumin itself.5 In general, i t has been observed that the presence of a His residue in the third position in tri-and tetrapeptides enhances their ability to bind copper.6 The synthetic tripeptide sequence, Gly-Gly-His, mimics well the Cu(1I) binding site of human serum alb~min.~.8 At physiological pH, one Cu(I1) ion is bound per mole of tripeptide, with a.complex dissociation constant on the order of 1 X 10-17M.7 We have anchored the tripeptide unit, Gly-Gly-His, to a polymeric matrix with the aim of obtaining a macromolecular adduct with a high affinity for copper. Samples of poly(L-lysine) have been derivatized to a product in which side-chain amino groups have been modified according to the following structure: