Deoxyhypusine Hydroxylase/Monooxygenase (DOHH)

DOHH encodes a metalloenzyme that catalyzes the last step in the conversion of lysine to the unique amino acid hypusine in eukaryotic initiation factor 5A. The encoded protein hydroxylates deoxyhypusine to form hypusine in the mature eukaryotic initiation factor 5A protein. Alternative splicing results in multiple transcript variants.DOHH contains 8 heat repeats organized in a symmetrical dyad connected by a variable region. It contains 2 potential metal coordination sites, each composed of 2 strictly conserved his-glu motifs.CD spectroscopy of purified recombinant wildtype DOHH indicated an alpha-helix-rich protein,and site-directed mutagenesis showed that the alpha-helical structure of DOHH does not depend on the conserved his-glu motifs or metal binding.