Two teams of scientists claim to have found proteins [sciencemag.org] in ancient dinosaur bone fossils:
One study, led by Mary Schweitzer, a paleontologist from North Carolina State University in Raleigh who has chased dinosaur proteins for decades, confirms her highly controversial claim to have recovered 80-million-year-old dinosaur collagen. The other paper suggests that protein may even have survived in a 195-million-year-old dino fossil. The Schweitzer paper is a "milestone," says ancient protein expert Enrico Cappellini of the University of Copenhagen's Natural History Museum of Denmark, who was skeptical of some of Schweitzer's earlier work. "I'm fully convinced beyond a reasonable doubt the evidence is authentic." He calls the second study "a long shot that is suggestive." But together, Cappellini and others argue, the papers have the potential to transform dinosaur paleontology into a molecular science, much as analyzing ancient DNA has revolutionized the study of human evolution.
[...] The second paper, published this week in Nature Communications, goes back even further in time but offers weaker evidence, Cappellini says. In this work, researchers led by paleontologist Robert Reisz at the University of Toronto in Canada reported finding what they believe is collagen in a 195-million-year-old fossil rib from a large plant-eating dinosaur called Lufengosaurus that lived in what is now southwestern China. Reisz says his team's methods, called Raman spectroscopy and synchrotron radiation Fourier transform infrared microspectroscopy (SR-FTIR), can probe the chemical makeup of a sample without the need to purify it first, which lowers the risk of contamination. The rib, he and his colleagues report, absorbed infrared light in wavelengths that match those of collagen from modern animals.
Also at BBC [bbc.com].
Analyses of Soft Tissue from Tyrannosaurus rex Suggest the Presence of Protein [sciencemag.org] (DOI: 10.1126/science.1138709) (DX [doi.org])
'Protein' in 80-Million-Year-Old Fossil Bolsters Controversial T. rex Claim [sciencemag.org] (DOI: 10.1126/science.324_578) (DX [doi.org])
Protein power [sciencemag.org] (DOI: 10.1126/science.349.6246.372) (DX [doi.org])
This week's papers:
Expansion for the Brachylophosaurus canadensis Collagen I Sequence and Additional Evidence of the Preservation of Cretaceous Protein [acs.org] (DOI: 10.1021/acs.jproteome.6b00873) (DX [doi.org])
Evidence of preserved collagen in an Early Jurassic sauropodomorph dinosaur revealed by synchrotron FTIR microspectroscopy [nature.com] (open, DOI: 10.1038/ncomms14220) (DX [doi.org])