Diphthamide Biosynthesis Protein 7 (DPH7)

WDR85 is a WD repeat-containing protein that plays a role in the first step of diphthamide biosynthesis.WDR85 is a conserved protein with homology to yeast YBR246W, which is also involved in diphthamide biosynthesis. WDR85 contains WD40 repeats, often involved in protein-protein interactions. WDR85 may serve as a scaffold to coordinate the association (or dissociation) of enzymatic complexes required for the stepwise biosynthesis of diphthamide. Diphtheria toxin and exotoxin A inhibit host translation through ADP ribosylation of elongation factor-2 (EF2) and thus cause cell death. ADP ribosylation occurs on diphthamide, a posttranslationally modified histidine uniquely present in EF2 and conserved among all eukaryotes.WDR85 plays a role in the first step in diphthamide biosynthesis.