Enlarge Image

Antiviral drugs can wedge into a cavity within an active site of the N1 neuraminidase enzyme (blue) and stop the enzyme's action. Mutations in the enzyme (colored dots) can reduce the efficiency with which antiviral drugs such as Tamiflu bind, creating drug-resistant forms of the virus. Newly discovered drugs (green) lodge in the enzyme’s active site in a different location, possibly being able to knock out viruses that have become resistant to other drugs. Credit: Daniel Dadon and Jacob Durrant, University of California, San Diego