As more bacterial species grow resistance to established antibiotics, there is a stronger need than ever for alternative anti-bacterial drugs that can stave off infections. In a new study published in Proceedings of the National Academy of Sciences, researchers believe they have found a possible answer in the most unlikely of places – wasp venom.
Wasps may not be known for being our best friends, but scientists have found a powerful new molecule within their venom that is highly toxic but also contains impressive antimicrobial properties. When engineered by a team from the University of Pennsylvania, the derivative could attack and kill bacterial cells while doing far less damage to human cells than the original molecule.
“New antibiotics are urgently needed to treat the ever-increasing number of drug-resistant infections, and venoms are an untapped source of novel potential drugs. We think that venom-derived molecules such as the ones we engineered in this study are going to be a valuable source of new antibiotics,” said study senior author César de la Fuente in a statement.
The molecule, a small protein (or peptide) called mastoparan-L, is a key toxin in Korean yellowjacket wasp (Vespula lewisii) venom and is a known antibacterial agent. However, in its natural form it is only moderately toxic to bacteria, whilst also killing red blood cells and even causing a serious allergic reaction in some patients. Therefore, the protein needed modification if it were to be viable as a drug.
After identifying a key region of the peptide responsible for its interaction with the immune system and antimicrobial properties, the researchers went to work modifying it to hopefully increase its effectiveness against bacteria. The resulting peptide had increased antimicrobial properties, directly attacking bacterial cells while also increasing immune activity surrounding the infection. Furthermore, the new molecule was safer for use in humans, with less toxicity towards human cells.
The researchers believe by repurposing the wasp venom, a potent antimicrobial drug could be produced that is as effective as existing options. With multiple different variants of the mastoparan-L that are both antimicrobial and non-toxic to humans, the researchers hope that one or more of these will translate into a drug capable of fighting against bacterial resistance.
“The principles and approaches we used in this study can be applied more broadly to better understand the antimicrobial and immune-modulating properties of peptide molecules, and to harness that understanding to make valuable new treatments,” de la Fuente said.
Mastoparan-L has been compared to melittin, the active component of honeybee venom, which has recently been found to have potential anti-cancer applications. Venom is an untapped resource that more scientists are now looking towards for drug usage, and with so many recent advances, it is certainly a field to watch.