Biomimetic Mineralization with Enhanced Hydrogen-Bond Interactions for Protein Stabilization

Abstract

Various protein species exhibit great potential in industrial and therapeutic applications; however, these applications are still limited due to their fragility to high temperature. In this work, a strategy of biomimetic mineralization was performed to construct a condensed protein-calcium phosphate hybrid structure to improve the thermostability of proteins. The mineral ion precursor used in conventional method was replaced with a biomimetic nanocluster of calcium phosphate capped with triethylamine to provide extra linking site on the phosphate end of the mineral. Higher concentration of protein could be integrated within this new hybrid, and form a homogenous system of condensed structure. Spectrum of the hybrid indicated enhancement hydrogen bonds of interactions between the protein and the mineral, and resulted in better thermostability of the incorporated protein. By this method, lysozyme and catalase could maintain above 75% of their enzyme activity after 120 °C heating, and this new hybrid mineral outstood the conventional biomineralization strategy for longer period preservation of proteins. This research presents an alternative biomimetic platform for proteins preservation and provided insights into protein-mineral interactions, paving the way for better control and modification of protein in the future.