Engineered bacteria kill malaria parasite

JOHNS HOPKINS (US) — Genetically altered bacteria in mosquito guts can kill the parasite that causes deadly malaria without harming either the mosquitoes or the people they bite.

Researchers modified the bacterium, Pantoea agglomerans, to secrete proteins that are toxic to the malaria parasite but not to its insect or human hosts.

“In the past, we worked to genetically modify the mosquito to resist malaria, but genetic modification of bacteria is a simpler approach,” says Marcelo Jacobs-Lorena, senior author of the study published in the Proceedings of the National Academy of Sciences and a professor at Johns Hopkins Bloomberg School of Public Health.

“The ultimate goal is to completely prevent the mosquito from spreading the malaria parasite to people.”


Jacobs-Lorena and his colleagues found that their engineered P. agglomerans strains inhibited development of the deadliest human malaria parasite, Plasmodium falciparum, and rodent malaria parasite Plasmodium berghei by up to 98 percent within the mosquito. The proportion of mosquitoes carrying parasites decreased by up to 84 percent.

Many types of bacteria live in the digestive tracts of both humans and mosquitoes. The specific function of most of them is not known, but they do provide an opportunity for fighting a disease that kills more than 800,000 people worldwide each year, Jacobs-Lorena says.

“These findings provide the foundation for the use of genetically modified symbiotic bacteria as a powerful tool to combat malaria,” Jacobs-Lorena adds.

The research was supported by the National Institute of Allergy and Infectious Diseases, the Bill & Melinda Gates Foundation, the Johns Hopkins Malaria Research Institute, and the Bloomberg Family Foundation.

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