In enzymology, an arginyltransferase () is an enzyme that catalyzes the chemical reaction L-arginyl-tRNA + protein tRNA + L-arginyl-protein Thus, the two substrates of this enzyme are L-arginyl-tRNA and protein, whereas its two products are tRNA and L-arginyl-protein. This enzyme belongs to the family of transferases, specifically the aminoacyltransferases. The systematic name of this enzyme class is L-arginyl-tRNA:protein arginyltransferase. Other names in common use include arginine transferase, arginyl-transfer ribonucleate-protein aminoacyltransferase, arginyl-transfer ribonucleate-protein transferase, and arginyl-tRNA protein transferase. It has 2 cofactors: mercaptoethanol, and Cation. References EC 2.3.2 Enzymes of unknown structure