Nearly half of the world’s population lives in areas vulnerable to malaria. The disease kills roughly 450,000 people each year, most of them children and pregnant women. Malaria is spread by Anopheles mosquitoes and, over time, the mosquitoes have been developing resistance to the chemical insecticides that are used to control them. In addition, there is great concern about the toxic side effects of the chemicals used on the mosquitoes.
About 30 years ago, scientists identified a type of bacteria that kills Anopheles, but the mechanism was not understood. As a result, the bacteria could not be replicated or used as an alternative to chemical insecticides.
But now, an international research team, headed by researchers at UC Riverside, has identified the neurotoxin produced by the bacteria and has determined how it kills Anopheles. The work is described in a paper published in Nature Communications.
It took the team 10 years to achieve a breakthrough in understanding the bacteria. Modern gene sequencing techniques were the key.
While many neurotoxins target vertebrates and are highly toxic to humans, the neurotoxin that kills Anopheles mosquitoes does not affect humans, vertebrates, fish, or even other insects. Known as PMP1, the substance is not even toxic to mice when given by direct injection.
The team has applied for a patent on this discovery and hopes to find partners to help them develop the bacteria-based insecticide.
There is a high likelihood that PMP1 actually evolved to kill the Anopheles mosquito. This finding opens the door to new avenues of research into other environmentally friendly insecticides that would be targeted at other disease-spreading pests.
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Controlling deadly malaria without chemicals
Photo, posted June 9, 2018, courtesy of Mario Yardanov via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio.
