UK researchers discover first antibiotics originating from insects

Wednesday, September 8, 2010

A group of University of Nottingham, UK researchers, led by Simon Lee, found that brains of certain species of cockroaches and locusts contain substances toxic to antibiotic resistant organisms. The scientists considered the brain as the most vital part of the insect to protect and screened it for antibacterial activity. The results were positive, and scientists are analyzing brain chemicals to determine the one which plays a key role. The discovery could reveal new treatments for multi-drug resistant bacteria, also known as superbugs.

Escherichia coli
Image: National Institutes of Health.

The research focused on insects because of the relatively "unhealthy" environments they often live in. Lee stated that "insects often live in unsanitary and unhygienic environments where they encounter many different types of bacteria, it is therefore logical that they have developed ways of protecting themselves against micro-organisms."

Initially, the scientists screened whole insects, until they found that the brain is the best protected area. Lee commented, "Without [the brain] they die, whereas they can survive losing limbs such as legs. From the locust's point of view, it's important that the central nervous system is protected all the time against bacteria and other pathogens."

The brain chemicals extracts killed some superbugs. Further study and analysis showed that nine molecules killed food poisoning microorganism Escherichia coli, and seven of them killed Methicillin-resistant deathly Staphylococcus aureus.

The current work in progress is the identification of the exact chemical ingredients which are toxic for the superbugs. The researchers observed that the extracts stop working when exposed to protein-degrading enzymes. Hence the scientists supposed that some proteins are actively participating in the attack.

The extracts don't harm human cells, as the study showed, but Lee stressed that much work is needed, in order to yield more specific conclusions. "We're a long way from these being active drugs", he said.