Translating form into function

In the last 40 years, scientists have perfected ways to determine the knot-like structure of enzymes, but they’ve been stumped trying to translate the structure into an understanding of function – what the enzyme actually does in the body. This puzzle has hindered drug discovery, since many of the most successful drugs work by blocking enzyme action. Now, in an expedited article in Nature, researchers show that a solution to the puzzle is finally in sight. A team co-led by UCSF’s Brian Shoichet, Steven Almo of the Albert Einstein College of Medicine, and Frank Raushel of Texas A&M describes the first success “decrypting” an enzyme’s function from its structure. If their new strategy works with other enzymes, it should become a potent tool to determine how key enzymes work in the body. And since enzyme action is crucial to disease, the technique opens an efficient route to drug discovery, Shoichet say. Schoichet a professor of pharmaceutical chemistry and an investigator in the California Institute for Quantitative Biomedical Research, or QB3, based at UCSF. The team’s success came by modifying a technique called molecular docking, a computer-aided modeling strategy used to search for potential drugs. Docking works by allowing researchers to first determine the atom-by-atom structure of an enzyme and then screen many thousands of molecules for one that fits into the empty “active site” of the enzyme. Shoichet calls this a search for the missing piece of a jigsaw puzzle. A molecule that fits the enzyme’s active site will block its activity – just what many promising drugs do. The strategy works well for one kind of drug discovery -- finding molecules to fit in the active site and physically block enzyme action. But the research team sought to divine from an enzyme’s structure just what natural molecule triggers the enzyme into action -- fitting into the active site and enabling the enzyme to act as a catalyst. This was a search for the so-called substrate for the enzyme, a search that has never succeeded simply from knowing an enzyme’s configuration. ... "PhysOrg":[ http://www.physorg.com/news102517000.html]

---