The human coronavirus is responsible for up to 30% of common colds, which is a pretty irritating condition, but ultimately a mild one.
In 2002, however, a deadly new version of the virus emerged called Severe Acute Respiratory Syndrome
, or SARS. This killed 15% of those who became infected.
Tackling SARS with existing antiviral drugs has proven difficult but Yuan-Ping Pang
, a biophysicist at the Mayo Clinic in Rochester New York State, and colleagues think they may have found a chink in its armour.
The virus reproduces by making an enzyme called chymotrypsin-like cysteine proteinase or CCP, which catalyses the formation of the chemical building blocks needed to copy itself. In theory, CCP can be targeted by molecules called inhibitors that stop it working. But, so far, no drug that works in this way has made it through to clinical trials.
This patent however reveals a new molecule that could do the trick. The team simulated the shape of CCP on a computer and then searched through a database of molecules for one with a structure that could prevent it from working.
They settled on 12 candidates that looked as though they could do the trick and tested them on kidney cells from monkeys infected with the virus. One molecule called CS11 emerged as a non-toxic candidate that prevented SARS from reproducing.
The team also made another intriguing discovery. CS11 turns out to be structurally similar to Tamiflu, a drug currently used to tackle bird flu. So the authors hint that CS11 might perhaps also turn out to be a useful tool in preventing the spread of bird flu. It definitely looks like one to watch.
Read the full patent application for fighting SARS and bird flu