Regulation of in vitro Calcium Phosphate Mineralization by Combinatorially Selected Hydroxyapatite-Binding Peptides

Abstract

We report selection and characterization of hydroxyapatite-binding heptapeptides from a peptide-phage library and demonstrate the effects of two peptides, with different binding affinities and structural properties, on the mineralization of calcium phosphate mineral. In vitro mineralization studies carried out using one strong- and one weak-binding peptide, HABP1 and HABP2, respectively, revealed that the former exhibited a drastic outcome on mineralization kinetics and particle morphology. Strong-binding peptide yielded significantly larger crystals, as observed by electron microscopy, in comparison to those formed in the presence of a weak-binding peptide or in the negative control. Molecular structural studies carried out by circular dichroism revealed that HABP1 and HABP2 differed in their secondary structure and conformational stability. The results indicate that sequence, structure, and molecular stability strongly influence the mineralization activity of these peptides. The implication of the research is that the combinatorially selected short-sequence peptides may be used in the restoration or regeneration of hard tissues through their control over of the formation of calcium phosphate biominerals.

Molecular biomimetics: nanotechnology and bionanotechnology using genetically engineered peptides

“…Once this is achieved, peptide-based molecular scaffolds developed may have great potential for applications in tissue regeneration. An example from our recent work on biomineralization using hydroxyapatite (HA)-binding peptides (Gungormus et al 2008; M. Gungormus, D. Khatayevich, C. So, C. Tamerler & M. Sarikaya 2008, unpublished data) is shown in figure 5a,b. We demonstrated that the biocombinatorially selected HA-binding peptides could offer a route for regulating calcium phosphate-based nanocrystal formation within a biomedical context.…”

C-terminal Amidation of an Osteocalcin-derived Peptide Promotes Hydroxyapatite Crystallization

“…They could be derived from native proteins having conserved fragments in different organisms or created by artificial evolution (11). Several groups have used artificial evolutionary systems to identify HA-binding peptides (12)(13)(14). On the other hand, natural peptides are mostly fragments of bone tissue proteins that are known to be involved in the mediation of HA formation.…”

Threshold voltage control in organic thin film transistors with dielectric layer modified by a genetically engineered polypeptide

“…11,12 GEPIs have been studied for applications in interface engineering ranging from bionanotechnology 13 to bionanomedicine. 14 The conformation and structure of GEPIs are dependent on their composition and environment. By tuning the pH of its solution, the secondary structure of the peptide can be changed as a result of variation in hydrogen bonding and interaction between residues.…”