Discovering new drugs may be faster and easier when a Carolina grad’s research finds its way into the marketplace.
In the hunt for new drugs, scientists screen thousands of molecules, looking for the perfect fit—a drug, or ligand, that attaches snugly to its receptor, a target in the body—rather like a hand inside a glove.
Computer programs can determine which molecules fit, or bind, using information such as the shape of the molecule and charges of atoms inside it.
But molecules change shape and can bind to other molecules in numerous ways. So while computer programs can determine which molecules bind, they may not be able to tell which, out of hundreds of possibilities, would work best in experiments.
Pharmacy researcher Raed Khashan has found a new method of “scoring” all the possible ways a ligand and receptor bind.
Drug developers use other scoring methods to rank molecules based on the three-dimensional orientation of atoms. But Khashan says those methods are based on orientations of two atoms or two groups of atoms, while his method takes into account more atoms and atom groups.
Khashan uses a computer to store, or memorize, the three-dimensional arrangement of atoms in the space where the ligand and receptor attach to each other. The memorized structures are drug molecules that are known to attach to specific receptors.
When scientists look at a completely new ligand and receptor, they can judge how closely the atoms in the attachment space match the memorized structure. “The closer to your memorized structure, the higher the score,” Khashan says.
Using this scoring method, drug developers could more accurately determine whether it’s worthwhile to invest time and money into producing and testing a particular ligand, Khashan says. They can even modify the ligand to make it bind more strongly to its receptor, he says.
Before it can be put to use by drug companies, Khashan’s scoring method needs to attract the interest of software designers, who would then produce and market his method to drug developers as part of a computer program.
Khashan presented his findings in August at the American Chemical Society’s national meeting.
Sarah Whitmarsh was a student who formerly contributed to Endeavors.
Raed Khashan received his doctoral degree in May 2007 from the pharmacy school’s Division of Medicinal Chemistry and Natural Products. He won a Chemical Computing Group Excellence Award from the American Chemical Society’s Division of Computers in Chemistry for his work.