NEW STRATEGY FOR AMELOGENIN CRYSTALLIZATION

University Of Southern California, Los Angeles CA

Investigators

Linked publications & trials

Abstract

DESCRIPTION (provided by applicant): In dentistry as well as in other biomedical and clinical fields, there is a growing need to develop novel and improved biomaterials. Tooth enamel represents a tissue that may be restored with biomimetic strategies. The future long-term objective of this proposal is the development of novel and biomimetic mineralized materials as an alternative to current dental restorative material. To develop biomimetic strategies the basic and critical events of biomineralization such as protein structure and assembly (protein-protein interactions), and nucleation and growth of minerals (protein-mineral interactions) need to be characterized. Structural determination of proteins involved in controlling the process of biomineralization is a critical step toward development of biomimetic biomaterials. We postulate that the processes of crystal nucleation and growth modulation during enamel biomineralization are mediated through specific interactions between structural domains on amelogenin protein with itself (nanosphere assembly), non-amelogenin proteins such as enamelin, ameloblastin, proteinases as well as the mineral phase. Knowledge on the tertiary structure of amelogenin will elucidate the structure and orientation of these specific domains. This proposal is based on the perceived need to fabricate biomimetic "enamel-like" material as an alternative to current dental restorative materials. Considering the notion that one of the impediments is the lack of detailed understanding of the 3-D structure of amelogenin, this proposal focuses on developing an innovative technique for successful crystallization of amelogenin, a critical step towards the resolution of its three dimensional structure. The strategy is to crystallize amelogenin through heterogeneous nucleation from surface nucleators. We plan to achieve this goal through the following specific aims: I. To develop and characterize surfaces for amelogenin adsorption in a monomeric state, which will be used for its crystallization, using Optical Wavelength Light Spectroscopy (OWLS), Scanning Angle Reflectometry (SAR) and Ellipsometry. II. To carry out crystallization trails of amelogenin on a series of substrates as active nucleant surfaces to obtain X-ray diffraction quality single crystals. If the crystallization trails are successful and large single protein crystals can be prepared, a significant future research plan (R0I proposal) involving the steps of data measurements, phase determination, electron density map computation and interpretation, and model refinement can be developed.