Article from PLoS: Dinosaur Peptides Suggest Mechanisms of Protein Survival

[Wayne Callahan <callahans2@msn.com>]

Read the open-access, full-text article here:
http://dx.plos.org/10.1371/journal.pone.0020381
 

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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.