DPH2, also known as diphthamide biosynthesis protein 2, is a homodimer and each of its monomers can bind a [4Fe-4S] cluster. It is the target of ADP ribosylating diphtheria toxin (DT) and Pseudomonas exotoxin A (PE). It was identified by its ability to complement a diphthamide mutant strain, and thus functions in diphthamide biosynthesis. Its loss pre-activates NF-?B and death receptor pathways and renders MCF7 cells hypersensitive to tumor necrosis factor. Recombinant human DPH2, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.