SYDNEY, Oct. 1 (UPI) -- Australian researchers said they have found that flies could be a source of new drugs to fight deadly bacteria.
"We asked the question, 'Where would antibiotic production be most likely to be found?'" Andrew Beattie, research supervisor at Macquarie University, told United Press International. "We thought that a good place to start looking would be in micro-organisms in close contact with dung and dead bodies where the microbial challenge is extremely high."
Beattie said the search was narrowed further to "social insects," which, the team hypothesized, should have a richer array of anti-microbial properties than "solitary insects." That theory eventually led to flies.
In particular, the scientists looked at the common house fly, the sheep blow fly, the vinegar fly and the Queensland fruit fly -- all of which Australia has in abundance. They found the flies produce robust antibiotic defenses that help them live off dung, dead animals and rotten food.
"In the case of dung, the flies compete for food with bacteria and fungi, and so have to protect themselves from attack," Beattie said. "Our research leads us to believe they do this by producing antibiotics."
Joanne Clarke, another researcher on the project, told UPI all the fly species she analyzed produce antibiotics on the surface during the adult and larval stage, but only occasionally during the pupae stage when they have a protective casing. She harvested the antibiotic from the surface of the flies by soaking them in ethanol for a few days, then removed the ethanol from the solution, leaving just the fly's secretions.
"We tested the secreted antibiotic on three types of bacteria," Clarke said, including golden staph and the common gut bug, E. coli and a yeast, "and the antibiotic killed them all."
Although the findings offer fresh hope in the battle against a variety of superbugs that are becoming increasingly resistant to antibiotics, it is far too early to declare victory. Beattie said an enormous amount of work is needed before a pharmaceutical could be developed.
"This is a step forward, but we need to know more about the type of molecules washed off the flies to understand how significant the research will be," Stephen Trowell, chief scientific officer at Entocosym, told UPI. Entocosym was formed by Australia's Commonwealth Scientific & Industrial Research Organisation to derive drugs from insects. "It's a long shot at this point, but in the end, some of the long shots win," he said.
Clarke said although most drug research focuses on plants, of which there are around 250,000 species on Earth, to date the world's 4 million insect species have been left virtually untouched in the drug-development hunt, even though they utilize an unparalleled range of biologically active substances. These include molecules that kill cancer cells, proteins that prevent blood from clotting and enzymes that degrade pesticides, she said.