Interaction Between Tripeptide Gly-Gly-His and Cu2+ Probed by Microcantilevers

✍ Scribed by Ying-Ming XU; Hong-Qing PAN; San-Hua WU; Bai-Lin ZHANG

• Book ID: 104452569
• Publisher: Elsevier Science
• Year: 2009
• Tongue: Chinese
• Weight: 341 KB
• Volume: 37
• Category: Article
• ISSN: 1872-2040
• DOI: 10.1016/s1872-2040(08)60106-1

✦ Synopsis

Gly-Gly-His (GGH) tripeptide was covalently attached onto a 3-mercaptopropionic acid (MPA) modified gold surface of microcantilever, and its interaction with Cu 2+ was studied by microcantilever method. It was found that at a relatively high concentration of Cu 2+ , the cantilever bent toward the gold side initially with a tensile surface stress, which might be due to the N atom of imidazole ring and carboxyl group in different peptide coordinate with Cu 2+ . The reversal deflection of microcantilever was observed immediately, which suggest that the peptide-Cu 2+ complex are formed with conformation transition. At a relatively low concentration of Cu 2+ , only the process of conformation transition was observed because the coordination mode might not be formed initially. The influences of pH and concentration of Cl -on the process above were studied. The results show that the maximum deflection was obtained at pH 7, and the bonding of Cu 2+ to the Gly-Gly-His tripeptide was inhibited because of the formation of CuCl x 2-x .