Furin is a proprotein convertase, converting precursor proteins to functional proteins within the Golgi/trans-Golgi secretory pathway. Furin inhibitor I is a selective, irreversible, and cell-permeable competitive inhibitor of proprotein convertases, including furin/SPC1 (Ki = ~1 nM), SPC2/PC2 (Ki = 0.36 nM), SPC3/PC1/PC3 (Ki = 2.0 nM), SPC4/PACE4 (Ki = 3.6 nM), SPC6/PC5/PC6, and SPC7/LPC/PC7/PC8 (Ki = 0.12 nM). Because furin activates viral glycoproteins, this inhibitor is a useful antiviral agent. In addition, it inhibits furin-dependent pro-MMP-2 activation in mononuclear inflammatory cells.
