Deoxyhypusine hydroxylase from rat testis. Partial purification and characterization.
Deoxyhypusine hydroxylase, the enzyme that catalyzes the formation of hypusine from deoxyhypusine in eukaryotic initiation factor 4D, has been partially purified from rat testis. The partially purified enzyme requires only the addition of certain sulfhydryl compounds for catalytic activity, dithiothreitol being the most effective. Its lack of dependency on the alpha-keto acid-dependent dioxygenase cofactors, Fe2+, alpha-ketoglutarate, and ascorbic acid, its failure to decarboxylate stoichiometrically alpha-ketoglutarate with deoxyhypusine hydroxylation, and its strong and specific inhibition by Fe2+ all suggest a catalytic mechanism of this enzyme unlike that of the prolyl and lysyl hydroxylases.
D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism; D002850:Chromatography, Gel; D006224:Cricetinae; D003412:Cricetulus; D004229:Dithiothreitol / Q000494:pharmacology; D005260:Female; D005290:Ferric Compounds / Q000494:pharmacology; D006168:Guinea Pigs; D007656:Ketoglutaric Acids / Q000378:metabolism; D007700:Kinetics; D008297:Male; D006899:Mixed Function Oxygenases / Q000302:isolation & purification*; D010053:Ovary / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D013737:Testis / Q000201:enzymology*; D014018:Tissue Distribution
D005290:Ferric Compounds; D007656:Ketoglutaric Acids; C024823:ferric sulfate; D006899:Mixed Function Oxygenases; C047991:deoxyhypusine hydroxylase; D001205:Ascorbic Acid; D004229:Dithiothreitol