Understanding nanocalcification: a role suggested for crystal ghosts

Area of Science:

• Biomineralization
• Biochemistry
• Materials Science

Background:

• Calcification in bone and hard tissues is a complex biomineralization process.
• The precise nature of initial inorganic particles in calcification has been debated.
• Understanding the organic-inorganic interplay is crucial for comprehending hard tissue formation.

Purpose of the Study:

• To investigate the initial stages of calcification in bone and hard tissues.
• To elucidate the organic-inorganic relationship during early calcification.
• To characterize the transformation of inorganic particles during this process.

Main Methods:

• Utilized electron microscopy to examine the structure of early calcification particles.
• Analyzed the composition and organization of organic and inorganic components.
• Investigated the role of specific organic structures in mineral stabilization.

Main Results:

• Electron microscopy demonstrated that early calcification particles are organic-inorganic hybrids, not crystalline.
• Identified a filamentous organic component, the 'crystal ghost,' composed of acidic proteins.
• Observed that crystal ghosts bind and stabilize amorphous calcium phosphate.

Conclusions:

• Crystal ghosts play a templating role in the formation of biological crystallites.
• The degradation of crystal ghosts facilitates the transformation of amorphous calcium phosphate into hydroxyapatite.
• While the complete mechanism of biological calcification remains under investigation, crystal ghosts are integral to the process.