Yes, mRNA Cap 2'-O-Methyltransferase can be simultaneously used with the Vaccinia capping enzyme in a one-step reaction. This involves capping and methylation of the RNA in the same reaction. The Vaccinia capping enzyme adds the m7G cap at the 5’ end of the RNA to produce capped RNA. The 2’-O-methyltransferase utilizes this RNA as a substrate and adds a methyl group at the 2’-O position of the first transcribed nucleotide to produce cap-1 RNA. Refer to the protocol section for reaction set up.