Microgel Enzyme Inhibitor

A polymer formed around an enzyme—a construction known as a molecularly imprinted polymer (MIP)—can selectively inhibit the enzyme much better than a related small-molecule inhibitor, indicating that MIPs could be useful for drug development (J. Am. Chem. Soc., DOI: 10.1021/ja901600e). Scientists have had aspirations of using MIPs for analytical chemistry and biochemical applications, but the biological activity of the molded macromolecules has remained unprobed. A group led by Karsten Haupt of Compiègne University of Technology, in France, targeted the protease trypsin by linking one of the enzyme’s known inhibitors, benzamidine, to methacrylic acid to make a polymerizing agent. The researchers then used the benzamidine-methacrylate combo as an anchoring point to synthesize polymer microgels around trypsin molecules. After removing the trypsin template, they tested the resulting MIPs’ ability to inhibit protease activity. They found that the MIPs inhibit the enzyme nearly 1,000 times better than benzamidine alone and that the inhibition is selective for trypsin over two related enzymes. In addition to functioning as enzyme inhibitors, Haupt and colleagues suggest that MIPs could be developed for other protein interactions to control different kinds of biological activity.