Methyltransferases are a diverse group of enzymes that function to methylate protein, DNA, and small molecule targets. Accordingly, methyl transferase activity plays a critical role in modulating gene transcription, protein interactions, and signaling networks. Anomalous DNA methylation pattern has been consistently detected during cancer development as well as in many genetic disorders such as Fragile X Syndrome, ICF, and Rett Syndrome. Assay Genie's Methyltransferase Activity Fluorimetric Assay Kit allows for kinetic evaluation of methyltransferase activity of purified enzymes. The transfer of a methyl group from S-Adenosyl Methionine (SAM) cofactor to a corresponding substrate generates S-Adenosyl Homocysteine (SAH) product. SAH is detected by coupling the methyl transfer reaction to a multi-step enzymatic cascade, resulting in the generation of an intermediate that reacts with GenieRed Probe. The fluorescent product is measured at Ex/Em = 535/587 nm. The limit of quantification (L.O.Q) is 7.5 pmol of SAH generated per min per ml (7.5 µU/ml) in purified enzymes.

Figure: a) SAH Standard Curve; b) representative activity curve for human recombinant Protein Arginine Methyltransferase 1 (hPRMT1) with Histone H4 Substrate at 25°C. Assays were performed using kit protocol.