'Resurrecting' the legendary figure behind Count Dracula

The legendary figure's official title was Vlad III, Voivode of Wallachia, and he lived in the southern region of Romania in the mid-1400s. Of course, there's no evidence that Vlad III was a vampire, but he was feared for his ruthlessness. Some estimates place his death toll at over 80,000 people, many dying by impalement, earning him his nickname. He was also referred to as Vlad Drăculea, translating to "the son of the dragon," which many believe inspired the eponymous character from the novel Dracula.

虽然已经过去500多年弗拉德的丽gn, some artifacts have remained, including several letters he penned at different points throughout his life. The molecules and proteins present on documents and other relics like these can provide scientists with a unique understanding of the life and times of people from the past. So, Vincenzo Cunsolo and colleagues wanted to, for the first time, investigate these letters to learn more about the health of the infamous Vlad Drăculeaa, as well as the environment he lived in.

To uncover the letters' secrets, the researchers used a specialized plastic film called EVA, or ethylene-vinyl acetate, to extract any proteins or small molecules from the paper without damaging it. These extracts were then analyzed with mass spectrometry, allowing researchers to characterize thousands of different peptides. Of these, the team focused on those with the most advanced deamidation, a form of protein degradation that occurs with age. The most degraded proteins were likely the oldest, and therefore, they are the most likely to be from Vlad compared to newer, less-degraded proteins that could have originated from other people handling the letters more recently. A total of 16 proteins were of human origin, relating to skin, breathing and blood.

The researchers say that the data they acquired, although not exhaustive, suggest that Vlad could have suffered from respiratory issues, and potentially even a condition called hemolacria, which would have caused him to cry tears of blood -- quite fitting for such a spooky character. Other proteins identified by the team indicate that he could have been exposed to certain, plague-related bacteria or even pesky fruit flies. In all, the researchers say that this work helps shed light on some important documents of the past, as well as the people who may have written them.