Protein Structure and Surface Interactions of an Enamel Protein
EMSL Project ID
26707
Abstract
The structure and protein-surface interaction of an enamel protein, amelogenin, will be investigated both on and off of hydroxyapatite using solid state NMR. The formation of nanospheres (protein aggregates) as amelogenins functional form has limited the utility of solution state structure determination and x-ray crystallography. Due to the limited number of charged residues, the residues thought to control protein-mineral interaction, isotopically labeled proteins can be recombinantly produced which contain only 2 or 3 labeled residues. There is some evidence that the higher field will allow the similarly labeled residues to be chemically shifted from one another, allowing structure determination from the chemical shifts of both backbone 15N and 13C residues, which respond very predictably to changes in structure. If adequate resolution is achieved, REDOR will be used to measure quanitative residue-surface distances to determine which residues are essential to protein binding. If inadequate resolution is obtained, the increased CSA for sidechain 15N and 13CH2 residues will allow the determination of dynamics on and off the surface, providing a qualitative but direct measure of protein-surface interaction. Because of the postulated importance, the charged residues will be the focus of study for both structure and protein-surface interactions. The structure and interaction will be investigated under a variety of conditions, all present during the formation of enamel, and possibly critical in determining the changing role of amelogenin during enamel formation. If successful, this work will provide structural and protein-surface interaction information that has not been previously accessible due to lack of experimental techniques, and the proposal demonstrates the need for high field to provide adequate resolution, sensitivity and large CSAs. Not only will the results provide critical information for enamel formation, but the results will have implications for other biomineralization proteins and will provide insight into the development of "smart" biomaterials.
Project Details
Project type
Capability Research
Start Date
2007-10-01
End Date
2009-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members