Scientists imbue cells with pathway to make own drugs

Thank the rare crested ibis for a clue that could someday help our bodies make better drugs.

The species of bird is the only one known to naturally produce an enzyme able to generate a noncanonical amino acid; that is, one not among the 20 necessary to encode most proteins.

That it exists — a discovery made through computational comparison of genome databases — proves it’s possible for that enzyme to work within the context of living cells, even if scientists don’t know what it does for the bird.

But they have a pretty good idea of what it could do for us.

A new study by Rice University chemist Han Xiao, theoretical physicist Peter Wolynes and their colleagues shows that amino acid, sulfotyrosine (sTyr), a mutant of the standard amino acid tyrosine, is a key building block to program living cells that express therapeutic proteins. It could potentially allow cells to serve as sensors that monitor their environments and respond with the necessary treatment.

Mimicking the ibis’ ability to synthesize sTyr and incorporate it into proteins requires modifying a cell’s DNA with a mutant codon that, in turn, makes the transferase enzyme, sulfotransferase 1C1, found in the bird. This catalyzes the generation of sTyr, an essential recognition moiety in a variety of biomolecular interactions.

Source: Read Full Article