WHAT’S BEING CLAIMED:
- Although wasp venom can be dangerous to humans, they can also kill bacteria, according to a study at MIT.
- Using a peptide that came from a wasp in South America, the scientists have developed an antibiotic that is not resistant to bacteria.
- Human embryonic kidney cells grown in the lab were tested to determine the safe dose for humans.
Wasps can be a danger to humans. Their stings are usually painful, but in some cases, people may suffer anaphylactic shock that may be life-threatening.
However, wasp venom can destroy bacteria as well. In a research that was published in the Communications Biology journal, MIT scientists have just unraveled how to remove the “dangerous” part of the venom while retaining the bacteria-killing part.
“We’ve repurposed a toxic molecule into one that is a viable molecule to treat infections,” said Cesar de la Fuente-Nunez, a microbiologist and immunologist at MIT.
As a defense mechanism against infection, all classes of life on earth produce antimicrobial peptides. This is a short chain of amino acids that eliminate microbes by disrupting their cell membranes. To fight these “superbugs”, a new group of antibiotics in which bacteria have no resistance is being developed.
A particular peptide consisting of only 12 amino acids from the venom of a South American wasp called Polybia Paulista was discovered as a potential target. According to de la Fuente-Nunez, this peptide can be mutated to as many amino acid residues as possible to test how they contribute to antimicrobial activity and toxicity.
To test how well they interacted with the cell membranes, a few dozen variants of the peptide were developed and tested against 7 species of bacteria and 2 fungi. From these, the team sorted out which of the peptides’ structures and physiochemical properties were most effective against microbes, and were refined accordingly.
To establish dose levels safe for humans, lab-grown human embryonic kidney cells were employed to test its toxicity on humans.
Finally, the peptides were ready for testing on live mice. These animals were infected with a bacteria called Pseudomonas aeruginosa which is antibiotic-resistant that is dangerous particularly to people with weak immune systems.
Several of the tested peptides showed varying degrees of success in reducing levels of infection. One particularly stood out-it completely obliterated P. aeruginosa at a high enough dose.
“After four days, it was quite surprising and exciting that that compound can completely clear the infection,” says de la Fuente-Nunez. He also noted that they don’t normally see those effects with other experimental antibiotics that they’ve tested in the past with the same mouse model that was used.
While the research does need further work, the findings are quite promising. Even if the wasp venom ends up being a dead end, still the researchers believe that the methods they have developed can be used in the search for a wider range of solutions-which is something we all need.
Source: Science Alert