Description
In archaea and eukarya selenocysteine formation is achieved by a two-step process: O-phosphoseryl-tRNASec kinase (PSTK) phosphorylates the endogenous L-seryl-tRNASec to O-phospho-L-seryl-tRNASec, and then this misacylated amino acid-tRNA species is converted to L-selenocysteinyl-tRNASec by EC 2.9.1.2 (Sep-tRNA:Sec-tRNA synthase)