NMR identification of anti-influenza lead compound targeting at PA_C subunit of H5N1 polymerase

PA_C subunit from avian influenza（H5N1） viral RNA polymerase was used in this work as a target in the screening for anti-influenza agents from licorice-derived compounds.As a result,18β-glycyrrhetinic acid was suggested to be PA_C ligand by flexible docking,and was then confirmed by relaxation-edited NMR.The result of ApG primer extension assay indicated that this PA_C ligand can inhibit the polymerase activity,and thus may potentially be valuable as anti-influenza lead compound.This work validated the possibility of screening polymerase inhibitors by using PA_C as a target,and provided a starting point for the further discovery of new anti-influenza drugs.