Guanylyltransferase 1,750 µg

Guanylyltransferase (GT), also known as Vaccinia Capping Enzyme (VCE), catalyzes addition of 7-methylguanylate cap structures (Cap 0) to the 5’ end of RNA in three steps:

Reactions 1 & 2: Conversion of an RNA substrate pppN(pN)n to GpppN(pN)n with increasing amounts of enzyme was visualized by gel electrophoresis (uncapped, lower band; capped, upper band). One unit (U) is the amount of enzyme activity that caps 50% of a 5’-ppp oligo in 30 minutes at 37°C.

Reaction 3: Methyl transfer from SAM to GpppN(pN)n producing SAH and cap-0 mRNA was measured using the EPIgeneous™ Methyltransferase Assay (Cisbio). One unit (U) is the amount of enzyme activity that produces 1 pmol of SAH from SAM in 30 minutes at 37°C using cap-0 substrate.