08/03 News Flash 5: Can a bean protein block SARS-CoV-2 infection?

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Image courtesy of Max Pixel.

As the COVID-19 pandemic worsens in many countries, scientists are continuing to look for new methods of treating the respiratory illness. In a study published in Cell Reports, researchers at the Academia Sinica, in Taipei, Taiwan, reported that a protein called FRIL, isolated from hyacinth beans, can neutralize influenza and SARS-CoV-2 virus particles. 

Viruses require a method of entry into the cell. Influenza cells use a protein called hemagglutinin (HA), while the novel coronavirus uses the spike (S) protein, for this purpose. The researchers noticed that both proteins are highly glycosylated, or bound to carbohydrate molecules. Because of the concentration of carbohydrates on these proteins, lectins, or proteins that preferentially bind to carbohydrate molecules, such as FRIL, could be used to target these proteins, preventing the viruses from entering the cell. After isolating FRIL, the researchers found that by binding to HA, FRIL could clump influenza particles together and prevent them from entering the cellular fluid, preventing infection. When given to mice, FRIL also protects against influenza infection. Importantly, they found that FRIL could also target the S protein, effectively blocking SARS-CoV-2 infection. These properties make FIL a promising candidate for treating both influenza and COVID-19.