L-seryl-tRNA(Sec) + selenophosphate + H(+) <=> L-selenocysteinyl-tRNA(Sec) + phosphate
l-seryl-trna(sec) + selenophosphate + h(+) <=> l-selenocysteinyl-trna(sec) + phosphate
L-seryl-tRNA(Sec) + selenophosphate + H(+) <=> L-selenocysteinyl-tRNA(Sec) + phosphate
l-seryl-trna(sec) + selenophosphate + h(+) <=> l-selenocysteinyl-trna(sec) + phosphate