Ancient dinosaur bone yields preserved collagen protein
Chicago (IL) - A team of American scientists has successfully analyzed eight fragments of preserved collagen protein found in an 80-million-year-old hadrosaur fossil. Although researchers led by Mary Schweitzer had previously extracted collagen from the fossilized remains of a 68-million-year-old Tyrannosaurus Rex, the results were marred by controversy over possible contamination of the sample.
"We didn't realize the level of criticism we would get from the earlier article," John Asara told Nature News. Asara, whose mass spectrometry lab at Harvard's Beth Israel Deaconess Medical Center sequenced the dinosaur proteins, expressed hope that the new study had moved "the field forward."
Schweitzer and her colleagues excavated parts of the hadrosaur skeleton in 2006. The team returned to the site in 2007 and removed an additional femur buried under seven meters of earth. The bone was still encased in sandstone, which helped to preserve structural proteins in the mineral lattice.
According to Schweitzer, the advanced methods used to extract and analyse the hadrosaur could help bring about a new era of paleontological field work — one where specimen scrutiny utilizes sterile techniques similar to a crime scene investigation. Rapid analysis of samples may also limit the potential of specimen degradation or contamination. For example, Schweitzer's team used a new portable laboratory to reduce the analysis timeframe from three-and-a-half weeks to eight hours.
Such techniques could significantly improve the next phase of Cretaceous fossil research for other proteins, including laminin and elastin. However, the presence of additional proteins has yet to be confirmed by mass spectrometry sequencing.
"It doesn't mean they aren't there. The mass spectrometry is not sensitive enough to sequence them," added Asara.
Hadrosaurids were herbivores that inhabited vast swathes of land across Asia, Europe and North America. Fossilized droppings indicate the animals consumed plants along with rotting wood, which contained nutrious fungi and invertebrates.