Histatin-3 TFA, a 32 amino acid peptide, possesses powerful antimicrobial properties. Histatin-3 TFA behaves as a substrate for proprotein convertase 1 (PC1), being cleaved by this endoprotease primarily at a site carboxy terminal to the single Arg25 residue (HRGYR decrease SN). Histatin-3 TFA is a moderately potent, reversible and competitive inhibitor of the furin-mediated cleavage of the pentapeptide pGlu-Arg-Thr-Lys-Arg-MCA fluorogenic substrate, with an estimated inhibition constant Ki of 1.98 μM.
References:
[1]. A Basak, et al. Histidine-rich human salivary peptides are inhibitors of proprotein convertases furin and PC7 but act as substrates for PC1. J Pept Res. 1997 Jun;49(6):596-603.