Translation elongation factor 2 (EF2) from archaea and eukaryotes contains a unique, post-translationally modified histidine residue called diphthamide, which is the target of diphtheria toxin. The biosynthesis of diphthamide involves three steps; here it is shown that the first step in the archaeon Pyrococcus horikoshii requires an unusual iron–sulphur-cluster enzyme, Dph2. It catalyses unprecedented chemistry.
- Yang Zhang
- Xuling Zhu
- Hening Lin