F-Amidine (trifluoroacetate salt)

Peptidyl arginine deiminase 4 (PAD4, Protein arginine deiminase 4) catalyzes the post-translational modification of arginine residues on histones to form citrulline, which plays a large role in regulating gene expression.¹ Dysregulated PAD4 activity has been implicated in cancer and rheumatoid arthritis.^1,2 F-amidine inhibits PAD4 activity with an IC₅₀ value of 21.6 μM in an in vitro activity assay.^3,4 It irreversibly inactivates (k_inact/K_I = 3,000 M^-1min^-1) PAD4 by covalently modifying an active site cysteine that is important for its catalytic activity.⁴ F-amidine also inhibits PAD1 and PAD3 with IC₅₀ values of 29.5 and 350 μM, respectively.⁵ F-amidine is cytotoxic to HL-60, MCF-7, and HT-29 cancer cell lines (IC₅₀s = 0.5, 0.5 and 1 μM, respectively).⁶

≥95%