Coronaviruses - the family of viruses that causes the common cold - gained widespread recognition when the deadly severe acute respiratory syndrome, familiarly known as SARS, killed at least 800 people in 2003.
Research efforts to design antiviral agents to combat coronaviruses intensified after the SARS epidemic and have focused mostly on just this virus. But because coronavirus sequences and structures mutate so quickly, a challenge is to find wide-spectrum vaccines, since a vaccine targeting one strain would likely be ineffective against another.
Online this week in the open-access journal PLoS Biology, Haitao Yang, Dawei Ma, Zihe Rao, and colleagues report that they have produced an antiviral inhibitor that is active against several coronaviruses. The authors combined structural and biochemical analyses to identify a target in the structurally conserved substrate-binding region of the main protease (Mpro). Since humans and other animals have no proteins similar to Mpro, the likelihood of deleterious side effects is low. The substrate-binding site is especially attractive as a target for drug development because evolutionarily conserved regions do not undergo high mutation rates like the rest of the viral genome, allowing antiviral drugs to maintain their effectiveness.