With S-adenosylmethionine (SAM) as the methyl group base donor, mRNA Cap 2´-O-Methyltransferase can add a methyl group to the 2´-O of the first nucleotide of the Cap0 structure, [m7GpppN1(pN)x-OH(3')], next to the RNA 5´ end. Methylation of capped mRNA from Cap 0 to Cap1 naturally exists in eukaryocyte, where the Cap1 structure shows an important effect for translation, thus for expression as well. This product doesn’t show a reactivity to RNA substrate other than RNA with Cap0 structure. This product is from a large scale GMP leveled recombinant Cap 2’-O-Methyltransferase production via E. coli expression. Applying pharmaceutical leveled adjuvant and material for production, strictly controlling host protein residues, nucleic acid residues and other impurities, we guarantee manufacture and quality control practice complying to GMP regulation, as well as all the materials traceable. This product has completed the DMF record of FDA and passed the HALAL certification. Figure 1. mRNA cap structure 2’-O-methyl transferase mechanism of action. The cap structure of mRNA is composed of a 7-methylguanosine connected to the 5′nucleoside of the mRNA chain through a 5’–5’ triphosphate bridge. The Cap-0 structure is formed by the sequential reaction of three enzymes between adjacent RNA strands. Further formation of cap-1 structure requires the participation of 2’-O-methyltransferase, and this modification can reduce the cellular innate immune response caused by RNA in vivo.This figure is quoted from Decroly, E., Ferron, F., Lescar, J. et al. (2012). Conventional and unconventional mechanisms for capping viral mRNA. Nat Rev Microbiol 10, 51–65.