Diphthine methyl ester synthase (DPH5)

S-adenosyl-L-methionine-dependent methyltransferase that catalyzes four methylations of the altered target histidine residue in translation elongation factor 2 (EF-2), to form an intermediate called diphthine methyl ester. The four successive methylation reactions represent the second step of diphthamide biosynthesis.

.