Could a molecule found in the venom of a southern African scorpion contribute to the development of new treatments for antibiotic-resistant infections?
Researchers at the University of Pretoria are investigating this possibility through Opis16a, a synthetic antimicrobial peptide derived from a molecule originally identified in the venom of Opistophthalmus carinatus, a scorpion native to southern Africa.From scorpion venom to antimicrobial researchOpis16a is a shortened version of a naturally occurring peptide called opistoporin 1. Researchers investigated its potential against drug-resistant bacteria, particularly Gram-negative pathogens.In laboratory experiments, Opis16a inhibited all 12 bacterial strains tested. These included multidrug-resistant strains of Acinetobacter baumannii, a hospital-associated bacterium capable of causing serious bloodstream, respiratory and wound infections.Unlike conventional antibiotics that often target specific bacterial processes, Opis16a works by disrupting bacterial cell membranes. Its positively charged structure allows it to interact with negatively charged bacterial surfaces, damaging their membranes and ultimately killing the cells.
The researchers also investigated its effects in an early infection model using Galleria mellonella (wax moth) larvae. At a tested dose of 10 mg/kg, 87% of larvae treated with Opis16a survived.Why does this discovery matter?Antimicrobial resistance (AMR) is a growing global health challenge. The ability of bacteria to survive treatments that previously controlled them makes infections increasingly difficult to manage.The search for new antimicrobial compounds is therefore essential. Natural biological resources, including plants, microorganisms and animal venoms, offer valuable starting points for drug discovery.This research demonstrates how African biodiversity can contribute to molecular innovation and the development of potential antimicrobial candidates.What happens next?Despite the encouraging findings, Opis16a is still experimental. Researchers must investigate its stability in wound environments, potential toxicity, manufacturing costs and effectiveness in more advanced animal models before human clinical trials can be considered.
The discovery is a reminder that biodiversity is not only an ecological resource. It can also be a source of scientific knowledge and future medical innovation.
Original research: "Scorpion venom-derived Opis16a shows potent membrane-destabilising Gram-negative activity and promising in vivo topical efficacy" (https://doi.org/10.1038/s44259-026-00266-9).
Additional reading: "Nature Africa – Can a scorpion-venom peptide tackle drug-resistant wound infections?" (https://www.nature.com/articles/d44148-026-00345-z).MyAfroDNA | Science, genetics and African health innovation.