Deoxyhypusine synthase gene is essential for cell viability in the yeast Saccharomyces cerevisiae

Abstract

Deoxyhypusine synthase catalyzes the first of two steps in the biosynthesis of hypusine, a modification of a specific lysine residue in the precursor of eukaryotic translation initiation factor 5A. We have purified deoxyhypusine synthase from yeast, and cloned and sequenced the corresponding gene encoding a 387‐amino acid protein from Saccharomyces cerevisiae. Gene disruption experiments indicated that the deoxyhypusine synthase gene is essential for cell growth in yeast. This gene was shown to be an intron‐free, single‐copy gene, and its product can catalyze the synthesis of deoxyhypusine equally in two precursor forms of eIF‐5A, derived from two distinct genes of yeast.