- If you are not yet a Down To Earth subscriber, please click here to subscribe: Subscription
- If you are an existing Down To Earth subscriber, please log in to download digital archives.
Bacteria in mangrove forests can eliminate mosquitoes
FROM sophisticated insecticides to genetic modification, scientists have tried every possible mechanism to eliminate menacing mosquitoes. But the measures only raised environmental concerns and resulted in sturdier mosquitoes. Scientists are, therefore, working hard to find out more biological control agents to combat the disease-spreading vector. The latest to join the arsenal are bacteria.
Scientists of the Vector Control Research Centre (VCRC) of the Indian Council of Medical Research in Puduchery have recently isolated a bacterium from mangrove forests, which they say can thwart the spread of vector-borne diseases like malaria, filariasis, dengue and chikungunya. They have also discovered the mechanism through which the bacteria kill the larvae and pupae of mosquitoes.
Previous studies have shown that mangrove forests harbour microorganisms that can kill mosquitoes. Last year, scientists in Tamil Nadu had found that the bacteria present in the soil and sediments of Muthupet mangrove are capable of combating malaria-spreading Anopheles mosquito. Taking their cue, VCRC researchers analysed microorganisms present in the soil of Andaman mangroves.
They collected soil samples from the creeks of Kalighat in North Andaman, separated bacterial cells from the soil samples and named them VCRC B483. They exposed the larvae and pupae of filariasis-spreading Culex quinquefasciatus, malaria-spreading Anopheles stephensi, and Aedes aegypti, which spreads dengue, chikungunya and yellow fever, to the bacteria. The bacteria secreted a lipopeptide, a biochemical, which killed the pupae and larvae of all the three mosquitoes. To identify the bacteria, the researchers carried out biochemical analysis and gene sequencing. It was Bacillus amyloliquefaciens.
“This is the first report on the mosquitocidal activity of B amyloliquefaciens,” says lead researcher A M Manonmani from the Unit of Microbiology and Immunology at VCRC. The study was published in the December 2011 issue of Acta Tropica.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.