Selenophosphate Synthetase 1 (SEPHS1)

Selenide, water dikinase 1 is an enzyme that synthesizes selenophosphate from selenide and ATP. Selenophosphate is the selenium donor used to synthesize selenocysteine, which is co-translationally incorporated into selenoproteins at in-frame UGA codons.Synthesizes selenophosphate from selenide and ATP.  ATP + selenide + H2O = AMP + selenophosphate + phosphate.The conserved active site Cys (or selenocysteine) residue in position 29 is replaced by a Thr. However, as function in selenoprotein synthesis is proven, it is possible Cys-31 is the active site.