Reaction: L-seryl-tRNASec + selenophosphate = L-selenocysteinyl-tRNASec + phosphate
Other name(s): L-selenocysteinyl-tRNASel synthase; L-selenocysteinyl-tRNASec synthase selenocysteine synthase; cysteinyl-tRNASec-selenium transferase; cysteinyl-tRNASec-selenium transferase
Systematic name: selenophosphate:L-seryl-tRNASec selenium transferase
Comments: a pyridoxal 5'-phosphate enzyme identified in Escherichia coli. Recognises specifically tRNASec-species. Binding of tRNASec also occurs in the absence of the seryl group. 2-Aminoacryloyl-tRNA, bound to the enzyme as an imine with the pyridoxal phosphate, is an intermediate in the reaction. Since the selenium atom replaces oxygen in serine, the product may also be referred to as L-selenoseryl-tRNASec. The symbol Sel has also been used for selenocysteine but Sec is preferred.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 183869-06-9
1. Forchhammer, K., Böck, A. Selenocysteine from Escherichia coli. Analysis of the reaction sequence. J. Biol. Chem. 266 (1991) 6324-6328. [PMID: 2007585]