MIT researchers are turning wasp venoms that are toxic to humans into antibiotics, which might aid in the fight against increasing threat of superbugs.
Wasp Venom's Antimicrobial Properties
Venoms of wasp and bees have peptides, a compound of two or more amino acids linked in a chain, that are known to be powerful antibacterials. However, the same compounds are often also toxic to human cells, making the use of insect venom as antibiotics almost impossible.
However, in a recent study published in the journal Nature, the researchers from MIT found a way to turn these peptides into effective antibiotics that will not be toxic to human cells.
The team used the venom of South American wasps on mice and found that it can easily kill Pseudomonas aeruginosa, a strain of bacteria that causes respiratory infections. According to the Centers for Disease Control and Prevention, Pseudomonas aeruginosa is also increasingly becoming difficult to treat. That is because the strain, similar to other hospital bacteria, has an increased antibiotics resistance.
The peptide that the researchers used in the study was small enough, with only 12 amino acids, making it easier to be manipulated.
"It's a small enough peptide that you can try to mutate as many amino acid residues as possible to try to figure out how each building block is contributing to antimicrobial activity and toxicity," explained Cesar de la Fuente-Nunez, an author of the study.
The team produced several variants with alpha-helical structure and varying degrees of hydrophobicity. Then, the team tested these peptides against seven strains of bacteria and two strains of fungus.
Based on these experiments, the researchers were able to produce a few dozen more variants that they tested on human embryonic kidney cells that were grown in a lab dish to measure toxicity. From there, they chose which compounds to use on mice infected with Pseudomonas aeruginosa. They were able to clear the infection after four days
Unfortunately, it might be long before wasp venom antibiotics hit the shelves. According to the researchers, they plan to create more variants of peptides that can effectively kill strains of bacteria in lower doses. They also hope to test other naturally occurring antimicrobial peptides in future experiments.
The Superbug Problem
Antibiotic resistance is a growing public health issue. In the United States, at least 2 million people get an antibiotic-resistant infection every year; 23,000 of them die.
The World Health Organization tagged superbugs as one of the greatest threats to human health. To combat the problem, the international public health agency is urging countries to invest in research that will develop new tools to address the threat. Regular people can help tackle resistance by using antibiotics as prescribed by doctors.