A Tasty Molecular Clue to Better Drugs

The savory flavor that makes it hard to stop eating flamin’ hot Cheetos could perhaps hold the key to delivering drugs more effectively.

Our tongues find this flavor, called umami, in protein-rich foods; it’s actually a response to glutamate (or glutamic acid). Dubbed the “fifth taste” (in addition to sour, salty, sweet, and bitter), umami was named by a Japanese scientist in 1908 and has come to prominence in the American consciousness more recently (it’s now being used to advertise soy sauce).

Now a California food-science company called Senomyx has uncovered the molecular mechanism that helps enhance umami flavor, and the discovery could not only lead to new flavor enhancers, but also help drug companies looking for molecules to deliver drugs more effectively.

As the researchers describe in the Proceedings of the National Academy of Sciences, a molecule that enhances the umami flavor–ribonucleotide inosine monophosphate–binds along with glutamate to two different targets on a common-type cell receptor called a GPCR (G protein-coupled receptor). The double binding helps enhance the signal.

Since GPCRs are implicated in many diseases and are the target of half of all drugs on the market, understanding this double binding could lead to drug combinations that work better at lower doses.