(Web Desk) - Scientists at the University of Münster have structured the mechanism behind the black widow’s deadly poison.
Specifically, the scientists have described the venom as “a cocktail of different toxins,” and they also zeroed in on a “a-latrotoxin.”
Designed by the forces of nature, this neurotoxin belonging to a class known as latrotoxins attacks vertebrates, including humans.
As most of us know, no one wants to mess with the iconic black spider with long killer legs. A bite can cause a range of adverse side effects in humans, from severe pain to spasms and even death, which makes their strategy so intriguing and mysterious, the scientists have never before understood its intricacies.
In a recent study, not only did University of Münster scientists discover that the deadly neurotoxin behaves differently than “all previously known toxins,” but understanding how it works will lead to “better antidotes, treatments for paralysis, and even new biopesticides.”
Professors Christos Gatsogiannis and Andreas Heuer used sophisticated technology to create a 3D model of a process in motion, to understand what happens to the neurotoxin once it enters the body, according to a press release by the university.
High-performance cryo-electron microscopy (cryo-EM) enabled them to study the architecture of the cells. Molecular dynamics (MD) computer simulations analyzed the physical movements of atoms and molecules.
With these tools, they could see how this moving neurotoxin with a potent, villainous effect functions in 3D. They might have known what a-latrotoxin does, but they didn’t know how it worked inside the body.
Upon entering the bloodstream, a-latrotoxin disturbs the “transmissions of signals in the nervous system.” The toxin undergoes a remarkable transformation when it binds to the receptor.
It interferes with the transmission of signals in the nervous system. As soon as α-latrotoxin binds to specific receptors of the synapses – the contacts between nerve cells or between nerve cells and muscles – calcium ions flow uncontrollably into the presynaptic membranes of the signaling cells.
This induces release of neurotransmitters, triggering strong muscle contractions and spasms.
Now, scientists understand the structure of this neurotoxin after insertion at “near-atomic resolution.”
They zoomed into the “influx of calcium” and discovered something unique. It transforms when it binds to the receptor. The toxic membrane “forms a stalk that penetrates the cell membrane like a syringe.” Astoundingly, it even “forms a small pore in the membrane that functions as a calcium channel,” which is how it floods the system.”
The scientists too were unaware of the complexities involved with the neurotoxin venom released by the Black widow spider. However, Professors Gatsogiannis and Heuer work in biophysics and physical chemistry, and they have the technology to understand the matter, literally, in 3D.
In previous work, Gatsogiannis deciphered the structure of black widow latrotoxins before they invaded the membrane. Now, they’ve figured out the structure of a previously unknown transformation that occurs once it binds to synapses and floods them with calcium, which throws off the whole body.
The MD simulations revealed that calcium ions can flow into the cell through a selective gate located on the side directly above the pore.
For being a tiny though mighty spider, the black widow developed a truly impressive defense mechanism that enables it to bring down giants comparatively. As the legend goes, go to the source if looking for the antidote. Due to its highly specialized functionality, we might even learn how to use this superpower to our advantage.