High-throughput selection of mineralizing peptides

Over 3.4 billion years of protein evolution, Mother Nature has refined molecular pathways that regulate and control biomineral formation. The exquisite hierarchical structures and multifunctional properties of biological hard tissues have long been inspired material scientists and engineers. These natural composites synthesized by proteins facilitate the nucleation and growth of inorganic solids, thereby directing mineral formation within organisms. Although biomineralization being essential for life, its dysregulation may lead to significant health issues. Understanding this mechanism is therefore crucial for developing treatments for diseases associated with abnormal mineral deposition. Inspired by biology at the nanoscale, the aim of this thesis was to identify short catalytic peptides that can govern hydroxyapatite (HAp) mineralization similar to natural proteins by deep directed evolution approach. Our results demonstrated the identification of several peptides with unique sequences. Structural characterization conducted through XRD and FTIR analyses confirmed the formation of hydroxyapatite in the presence of these peptides. Kinetic measurements further revealed that these peptides catalyze calcium phosphate mineralization 15 times faster under physiological conditions. The rapid mineralization kinetics exhibited by these peptides in an aqueous media supplemented with calcium and phosphate suggest a strong potential for restoring demineralized tissues and treating diseases related to pathological biomineralization. Furthermore, these peptide sequences could serve as foundational elements in the development of clinical products including dental gels and toothpaste formulations, as well as in treatments for bone regeneration and other medical applications where controlled mineralization is crucial.