Biomineralisation

Biomineralisation and Calciprotein particles

The minerals calcium and phosphate are indispensable for the cellular metabolism of all living organisms. Calcium is both a cellular messenger and an essential component in bones and teeth. Energy-rich phosphates are also instrumental in energy metabolism and control the action of signaling molecules. Both ions typically occur in millimolar concentrations in biological fluids. This creates a solubility and transport problem; calcium phosphates are poorly soluble in water and readily precipitate from supersaturated solutions. A similar transport problem exists with fats, especially cholesterol, which must also be transported in large quantities in the aqueous environment of the blood, but is virtually insoluble in water. If fats and minerals are colloidally stabilized with the help of proteins, transport in the body can take place.

Blood thus contains dissolved components as well as colloidally stabilized substances in addition to blood cells. Calciprotein particles (CPP) are colloidal protein-mineral complexes discovered at our Institute. CPP are formed in protein-containing solutions supersaturated with calcium and phosphate. In a protein-free solution with an excess of calcium and phosphate, crystalline calcium phosphate precipitates immediately. Proteins in the solution bind small calcium phosphate clusters and prevent their further growth into crystals, stabilizing the solution. We study the formation, structure and function of calciprotein particles in bone mineralization and pathological calcification. We measure the calcification risk in patients with disturbed mineral balance.