Model Studies on the Function of Acidic Proteins in Biomineralization

• Applicant: Professor Dr. Norbert Sewald
• Subject Area: Biological and Biomimetic Chemistry
• Term: from 2005 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5456662

The biological processes which lead to a wide variety of biomineral structures are largely unsolved. According to the widely accepted template-matrix-hypothesis , the organic matrix of calcified tissues (e.g. bones, mollusc shells) does contain specific macromolecules, which promote or inhibit the site-selective nucleation of crystals, and which direct the spatial orientation(s) of the overgrowing crystal layer. Owing to the very limited information which is currently available about the 3D structures of the natural matrix macromolecules, we are developing synthetic macromolecules (e.g. amphiphilic calixarene carboxylic acids and highly acidic peptides), which are specifically designed such as to mimic crucial aspects of the putative function of the biological systems. Essential structural properties of natural surface-active acidic proteins (i.e. binding epitopes comprising arrays of carboxylic acid residues fixed to amphiphilic b-pleated sheets, helices or loops) are imitated by artificial peptides. Elucidating the influence of the artificial proteins on the growth of inorganic crystal phases (calcite, aragonite, vaterite) within the appropriate model system is a main focus of our research, for which we employ monolayers and immobilized thin films in a perfusion device.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1117: Principles of Biomineralization