In a first attempt to test a new general strategy for drug discovery, chemists at The Scripps Research Institute (TSRI) and TSRI's Skaggs Institute for Chemical Biology created the most potent blocking agent known against an enzyme implicated in Alzheimer's disease.
In the current issue of the journal Angewandte Chemie, 2001 Nobel laureate K. Barry Sharpless, W.M. Keck Professor of Chemistry at TSRI, and colleagues at TSRI and the University of California at San Diego, describe how click chemistry, a modular protocol for organic synthesis that Sharpless developed, was used to make a drug-like molecule that powerfully blocks the neurotransmitter destruction caused by the brain enzyme, acetylcholinesterase.
Unlike existing methods, this new drug-discovery strategyclick chemistrymobilizes the target itself, acetylcholinesterase in this case, to play a decisive role and select the final synthetic step. The acetylcholinesterase enzyme actually catalyzed the click reaction that created that enzyme's own inhibitor, and, remarkably, the result is by far the most potent inhibitor ever discovered for this important, widely studied brain enzyme.
"Think of this as a Trojan Horse approach for battling disease, but this horse goes the Greeks one better," says Sharpless. "We create the pieces that can be clicked together to make the horse, then we leave them outside the gates of, for example, a bacterium. If the pieces look right, it goes to work, constructing its own worst enemy, and doing so within its own defensive walls."
"This is a breakthrough typical of Barry Sharpless," says TSRI President Richard Lerner. "For the first time, you are eliciting a contribution from the dynamic enzyme, asking it to make the inhibitor it prefers."
Finding inhibitors, molecules that fit snuggly into the active sites of a particular target and modulate its activities, is the basis for molecular medicine. Essentially all diseases operate by inducing unn
Contact: Robin B. Goldsmith
Scripps Research Institute