EOG8X6FQF	GO:0017183	25/87	peptidyl-diphthamide biosynthetic process from peptidyl-histidine	biological_process	"The modification of peptidyl-histidine to 2'-(3-carboxamido-3-(trimethylammonio)propyl)-L-histidine, known as diphthamide, found in translation elongation factor EF-2. The process occurs in eukaryotes and archaea but not eubacteria." [GOC:pde, PMID:20559380, RESID:AA0040]
EOG8X6FQF	GO:0004164	25/87	diphthine synthase activity	molecular_function	"Catalysis of the reaction: S-adenosyl-L-methionine + 2-(3-carboxy-3-aminopropyl)-L-histidine = S-adenosyl-L-homocysteine + 2-(3-carboxy-3-(methylammonio)propyl)-L-histidine." [EC:2.1.1.98]