For 75 years, researchers have known that opossums aren't fazed by poisonous snakes that can kill humans with a single strike. For about 25 years, they've known that a serum protein is responsible for that immunity.

Now scientists have harnessed that protein and hope to save some of the 20,000 people who die from snakebites each year, Gizmodo reports. Experts have synthetically manufactured a peptide—a chain of amino acids from the opossum protein, known as the Lethal Toxin Neutralizing Factor—that has neutralized bites on mice from diamondback rattlesnakes and the Russell's viper of Pakistan.

"It appears that the venom protein may bind to the peptide, rendering it no longer toxic," lead researcher Claire Komives explains, per Phys.org. What's even more impressive: The antivenom may also offset toxins from other venomous snakes, scorpions, plants, and bacteria, Komives adds.

Researchers were able to cheaply produce the peptide in E. coli bacteria, then purify it. Because it was so inexpensive and easy to mass-produce, researchers say the antivenom could be easily distributed to remote areas of India, South America, Southeast Asia, and Africa, where most fatal snakebites occur.

Not only that, the antidote doesn't carry the same side effects as other treatments. "The patient often has some kind of adverse reaction, such as a rash, itching, wheezing, rapid heart rate, fever, or body aches," Komives says.

Not so with the peptide, at least on mice. As such, the antivenom could likely be given in a single dose, rather than several smaller doses, Komives says.

CNET reports the antivenom will undergo further testing on mice; it isn't clear when human trials might begin. (A new antivenom for black widow bites is in the works.)

This article originally appeared on Newser: Bit by a Snake? An Opossum Could Save You

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