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 owing to their fragility to high temperatures. In this work, a biomimetic mineralization strategy was used to construct a condensed protein–calcium phosphate hybrid structure to improve the thermostability of proteins. The mineral ion precursor used in the conventional method was replaced with a biomimetic nanocluster of calcium phosphate capped with triethylamine to provide an extra linking site on the phosphate end of the mineral. A higher protein concentration could be integrated into this new hybrid, forming a homogeneous system of condensed structures. The spectrum of the hybrid indicated enhanced hydrogen bond interactions between the protein and mineral, resulting in improved thermostability of the incorporated protein. Applying this method, lysozyme and catalase could maintain more than 75% of their enzyme activity after heating to 120 °C, and this new hybrid mineral outperformed the conventional biomineralization strategy for long-term preservation of proteins. This research presents an alternative biomimetic platform for protein preservation and provides insights into protein–mineral interactions, paving the way for better control and modification of proteins in the future.