Molecular Simulation of Statherin Adsorption on Hydroxyapatite (001) Surface

Abstract

AbstractStatherin (SN) is an important protein that can adsorb on enamel to maintain calcium ions balance and promote biomineralization in the human oral cavity. In this work, parallel tempering Monte Carlo simulation and all‐atom molecular dynamics simulation are combined to study the behavior of SN adsorbed on the hydroxyapatite (HAP) (001) surface. The results indicate that SN can “anchor” on HAP (001) surface by its Asp1 and Sep2 with “head‐on” orientation in NaCl solution and its secondary structure and conformation are changed greatly, which means that SN loses its biological activity. However, SN can maintain its conformation in calcium phosphate solution. Furthermore, SN can adsorb on HAP (001) surface with Sep2 and Sep3 by salt bridge with calcium phosphorus clusters with “lying” orientation. More importantly, Glu26 residue can stabilize the free calcium and phosphorus clusters, which can prevent not only the dissolution of HAP surface, but also the precipitation of calcium phosphate due to the supersaturated state. This work can help to better understand the process of biomineralization and also provides a guidance for the design of dental restoration materials.