title: Dinosaur peptides suggest mechanisms of protein survival.
abstract: Eleven collagen peptide sequences recovered from chemical extracts of dinosaur bones were mapped onto molecular models of the vertebrate collagen fibril derived from extant taxa. The dinosaur peptides localized to fibril regions protected by the close packing of collagen molecules, and contained few acidic amino acids. Four peptides mapped to collagen regions crucial for cell-collagen interactions and tissue development. Dinosaur peptides were not represented in more exposed parts of the collagen fibril or regions mediating intermolecular cross-linking. Thus functionally significant regions of collagen fibrils that are physically shielded within the fibril may be preferentially preserved in fossils. These results show empirically that structure-function relationships at the molecular level could contribute to selective preservation in fossilized vertebrate remains across geological time, suggest a 'preservation motif', and bolster current concepts linking collagen structure to biological function. This non-random distribution supports the hypothesis that the peptides are produced by the extinct organisms and suggests a chemical mechanism for survival.
authors.affiliation: Operations, Orthovita, Inc., Malvern, Pennsylvania, United States of America. jsanantonio@orthovita.com
authors.forename: James D
authors.initials: JD
authors.lastname: San Antonio
authors.forename: Mary H
authors.initials: MH
authors.lastname: Schweitzer
authors.forename: Shane T
authors.initials: ST
authors.lastname: Jensen
authors.forename: Raghu
authors.initials: R
authors.lastname: Kalluri
authors.forename: Michael
authors.initials: M
authors.lastname: Buckley
authors.forename: Joseph P R O
authors.initials: JP
authors.lastname: Orgel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D024042:Collagen Type I / Q000737:chemistry* / Q000378:metabolism*; D017124:Conserved Sequence; D025061:Dinosaurs; D005580:Fossils; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry*; D010449:Peptide Mapping; D017433:Protein Structure, Secondary; D051381:Rats; D030162:Reptilian Proteins / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D024042:Collagen Type I; D010446:Peptide Fragments; D030162:Reptilian Proteins