February 2 0 , 2017:

Fossilized organic remains are important sources of information because they provide a unique form of biological and evolutionary information, and have the long-term potential for genomic explorations. Here we report evidence of protein preservation in a terrestrial vertebrate found inside the vascular canals of a rib of a 195-million-year-old sauropodomorph dinosaur, where blood vessels and nerves would normally have been present in the living organism. The in situ synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectra exhibit the characteristic infrared absorption bands for amide A and B, amide I, II and III of collagen. Aggregated haematite particles (α-Fe2O3) about 6∼8 μm in diameter are also identified inside the vascular canals using confocal Raman microscopy, where the organic remains were preserved. We propose that these particles likely had a crucial role in the preservation of the proteins, and may be remnants partially contributed from haemoglobin and other iron-rich proteins from the original blood.

Yao-Chang Lee, Cheng-Cheng Chiang, Pei-Yu Huang, Chao-Yu Chung, Timothy D. Huang, Chun-Chieh Wang, Ching-Iue Chen, Rong-Seng Chang, Cheng-Hao Liao & Robert R. Reisz (2017)
Evidence of preserved collagen in an Early Jurassic sauropodomorph dinosaur revealed by synchrotron FTIR microspectroscopy.
Nature Communications 8, Article number: 14220 (2017)
doi:10.1038/ncomms14220