Characterizations of a Food Decapeptide Chelating with Zn(II)

Abstract

Walnut proteins and peptides have been reported to have great zinc-carrying activity. In this study, the decapeptide EPNGLLLPQY (WP-10) derived from walnut protein has been prepared to figure out zinc binding mechanisms and structure–activity relationships. The space-conformation of this peptide has converted after being chelated with Zn(II). As to secondary structure, the β-sheet structure of the peptide turned into α-helix and β-turn structure. According to the atomic absorption spectra analysis, one peptide could bind with one Zn(II) via four different binding sites. The signals of different groups in infrared spectroscopy have shifted before and after chelation, and the major functional groups of this peptide involved in chelation are –NH2 and –C=O. GLU1, PRO2, ASP3, GLU4, and LEU6, and the molecular docking proved their participation in the chelating with Zn(II).

Keywords

• Peptide
• zinc
• binding sites
• molecular docking
• structure