There are few characters more representative of Halloween iconography than the Count. Yet Bram Stokers immortal villain (and let’s be honest, cruel and evil vampires are more compelling than sensitive suckers), isn’t the subject of today’s very late Day of Halloween. On the contrary, it’s his chemical namesake — draculin (desmoteplase).
Found in the saliva of vampire bats, desmoteplase was discovered in 1998. It is a glycoprotein that functions as an anticoagulant. It’s 411 amino acids long (though of course folded as proteins do). The way it works is that it prevents coagulation by inhibiting coagulation factors IX (aka Christmas Factor (not to mix metaphors but that’s the name)) and X (aka Stuart-Prower factor). By keeping its victim’s blood liquid, the vampire bat ensures itself a hearty meal.
Interestingly, a vampire bat’s daily salivation produces saliva that becomes less potent. Only after a few days of rest does the draculin content begin to regain its potency.
A few years ago, observant scientists figured out that the same enzyme that kept the blood flowing for hungry bats could potentially do the same for stroke patients. That led to intrepid researchers testing its activity in mouse brains. The 2003 study proved that draculin could be more effective than most of the commonly used coagulants. Three years later, a study tested the drug in humans. They discovered that desmoteplase was not only safe, but also well tolerated by patients.
A draculin-based drug is now in Phase II clinical trials.
How’s that for a Halloween-science tie-in?
IMAGE CREDITS: Creative Commons