Glycine-proline-hydroxyproline Modification Improves the Affinity of CEMP1 N-terminal 20-residue Peptide to Collagen

Abstract

N-terminal 20 peptide of cementum matrix protein 1 (CEMP1) shows the affinity for hydroxyapatite (HAP) and induces the nucleation of HAP. However, its poor affinity for collagen limits its application in periodontal tissue repair. Here, we found that modifying N20 peptides with collagen tripeptide composed of glycine-proline-hydroxyproline (GPH) can significantly promote N20 peptides binding to type I collagen rapidly, and improve the affinity of N20 peptides to bone powder and gingival fibroblasts. In addition, N20 peptides modified with GPH peptides can significantly increase the tightness of self-assembly of type I collagen, while N20 and individual type I collagen peptides only complete self-assembly in a loose stacking manner. Importantly, the modification of GPH does not affect the efficient interaction between N20 peptides and HAP particles. In summary, our research indicates that GPH modified peptides can significantly improve their affinity to collagen, providing a theoretical basis for further clinical applications of CEMP1-N20 peptides.