title: Asprich peptides are occluded in calcite and permanently disorder biomineral crystals.
abstract: Macromolecules are a minority but important component of the minerals formed by living organisms, or biominerals. The role these macromolecules play at the early stages of biomineral formation, as well as their long-term and long-range effects on the mature biomineral, is poorly understood. A 42-amino acid peptide, asp2, was derived from the Asprich family of proteins. In this study we present X-ray absorption near-edge structure spectroscopy and X-ray photoelectron emission microscopy data from the asp2 peptide, the calcite (CaCO(3)) crystals, and the peptide + crystal composites. The results clearly show that asp2 is occluded in fully formed biomineral crystals and slightly but permanently disorders the crystal structure at short- and long-range distances.
authors.affiliation: Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Metzler
authors.forename: Gareth A
authors.initials: GA
authors.lastname: Tribello
authors.forename: Michele
authors.initials: M
authors.lastname: Parrinello
authors.forename: P U P A
authors.initials: PU
authors.lastname: Gilbert
mesh_terms: D040761:Biomimetic Materials / Q000737:chemistry*; D002119:Calcium Carbonate / Q000737:chemistry*; D008968:Molecular Conformation; D010446:Peptide Fragments / Q000737:chemistry*; D056928:X-Ray Absorption Spectroscopy
chemical_list: D010446:Peptide Fragments; D002119:Calcium Carbonate