Genetically Engineered Bacteria New Weapon Against Malaria Transmission

Genetically Engineered Bacteria New Weapon Against Malaria Transmission

Researchers at the Johns Hopkins Malaria Research Institute have genetically modified a bacterium commonly found in the mosquito’s midgut and found that the parasite that causes malaria in people does not survive in mosquitoes carrying the modified bacterium. The bacterium, Pantoea agglomerans, was modified to secrete proteins toxic to the malaria parasite, but the toxins do not harm the mosquito or humans. According to a study published by PNAS, the modified bacteria were 98 percent effective in reducing the malaria parasite burden in mosquitoes.

“In the past, we worked to genetically modify the mosquito to resist malaria, but genetic modification of bacteria is a simpler approach,” said Marcelo Jacobs-Lorena, PhD, senior author of the study and a professor with Johns Hopkins Bloomberg School of Public Health. “The ultimate goal is to completely prevent the mosquito from spreading the malaria parasite to people.”

With the study, Jacobs-Lorena and his colleagues found that the 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 (prevalence) decreased by up to 84 percent.

“We demonstrate the use of an engineered symbiotic bacterium to interfere with the development of P. falciparum in the mosquito. These findings provide the foundation for the use of genetically modified symbiotic bacteria as a powerful tool to combat malaria,” said Jacobs-Lorena.

Malaria kills more than 800,000 people worldwide each year. Many are children.

The authors of “Fighting malaria with engineered symbiotic bacteria from vector mosquitoes” are Sibao Wang, Anil K. Ghosh, Nicholas Bongio, Kevin A. Stebbings, David J. Lampe and Marcelo Jacobs-Lorena.

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

Media contact: Tim Parsons, director of Public Affairs, at 410-955-7619 or tmparson@jhsph.edu.

The most vulnerable stages of Plasmodium development occur in the lumen of the mosquito midgut, a compartment shared with symbiotic bacteria. Here, we describe a strategy that uses symbiotic bacteria to deliver antimalaria effector molecules to the midgut lumen, thus rendering host mosquitoes refractory to malaria infection. The Escherichia coli hemolysin A secretion system was used to promote the secretion of a variety of anti-Plasmodium effector proteins by Pantoea agglomerans, a common mosquito symbiotic bacterium. These engineered P. agglomerans strains inhibited development of the human malaria parasite Plasmodium falciparum and rodent malaria parasite Plasmodium berghei by up to 98%. Significantly, the proportion of mosquitoes carrying parasites (prevalence) decreased by up to 84% for two of the effector molecules, scorpine, a potent antiplasmodial peptide and (EPIP)4, four copies of Plasmodium enolase–plasminogen interaction peptide that prevents plasminogen binding to the ookinete surface. We demonstrate the use of an engineered symbiotic bacterium to interfere with the development of P. falciparum in the mosquito. These findings provide the foundation for the use of genetically modified symbiotic bacteria as a powerful tool to combat malaria.

The bacterium, called Pantoea agglomerans, was modified to produce proteins toxic to the Plasmodium falciparum. The toxins reportedly don’t harm either mosquitoes or humans. The results of the study, which are published in Proceedings of the National Academy of Sciences, showed that the bacteria strains inhibited development of the human malaria parasite Plasmodium falciparum and rodent malaria parasite Plasmodium berghei by up to 98%. The genetically engineered bacteria are visible, as they glow fluorescent green inside the mosquito (see image). The ultimate goal is to completely prevent the spread of malaria, and this new weapon looks promising in the global battle against the disease.

Source : http://malaria.jhsph.edu/news/jacobs_lorena_bacteria.html

Related Posts Plugin for WordPress, Blogger...
Be Sociable, Share!

About the Author

has written 1822 posts on this blog.

Copyright © 2017 Medical Technology & Gadgets Blog MedicalBuy.net. All rights reserved.
Proudly powered by WordPress. Developed by Deluxe Themes