Cayman Chemical PAD4 Inhibitor Screening Assay Kit (Ammonia)

Cayman Chemical’s PAD4 Inhibitor Screening Assay Kit (Ammonia) provides a convenient method for screening human inhibitors of protein arginine deiminase 4 (PAD4), a guanidino-modifying enzyme that functions as a transcriptional co-regulator catalysing the conversion of specific arginine residues to citrulline.

PAD4 autocitrullinates itself at several sites, inhibiting its enzymatic activity. PAD4 activity is increased in rheumatoid arthritis, producing an abundance of citrulline-containing proteins that generate an immune response resulting in production of autoantibodies that ultimately attack the host tissues. PAD4 has also been implicated in several other diseases including multiple sclerosis, Alzheimer’s disease, glaucoma and cancer.

PAD4 results in the deimination of N-α-benzoyl-L-arginine ethyl ester (BAEE), a non-natural substrate with similar kinetic properties to the natural substrates, producing ammonia. Ammonia reacts with a detector resulting in a fluorescent product. Fluorescence is then analysed with an excitation wavelength of 405–415 nm and an emission wavelength of 470–480 nm.