Skin mucus secreted by a colourful, tennis-ball-sized frog species found in Kerala can be used to develop an anti-viral drug that can treat various strains of flu, according to a new study. Frog mucus is loaded with molecules that kill bacteria and viruses and researchers are beginning to investigate it as a potential source for new anti-microbial drugs. One of these "host defence peptides," found in a colourful tennis-ball-sized frog species (Hydrophylax bahuvistara) native of Kerala can destroy many strains of human flu and protect mice against flu infection, researchers said.
Researchers including those from Rajiv Gandhi Centre for Biotechnology in Kerala wondered if there might be peptides that neutralise human-infecting viruses. They screened about 32 frog defence peptides against an influenza strain and found that four of them had flu-busting abilities. "In the beginning, I thought that when you do drug discovery, you have to go through thousands of drug candidates, even a million, before you get one or two hits.
And here we did 32 peptides, and we had four hits," said Joshy Jacob of Emory University in the US. When the researchers exposed isolated human red blood cells in a dish to the flu-buster peptides, three out of the four proved toxic.
However, the fourth seemed harmless to human cells but lethal to a wide range of flu viruses, researchers said. The researchers named the newly identified peptide "urumin," after the urumi, a sword with a flexible blade that snaps and bends like a whip. Electron microscope images of the virus after exposure to urumin reveal a virus that has been completely dismantled, researchers said.
It seems to work by binding to a protein that is identical across many influenza strains, and in lab experiments, it was able to neutralise dozens of flu strains, from the 1934 archival viruses up to modern ones, researchers said. The study was published in the journal Immunity.
