S-methyl-L-methionine + L-selenocysteine = Se-methyl-L-selenocysteine + L-methionine + H(+)
s-methyl-l-methionine + l-selenocysteine = se-methyl-l-selenocysteine + l-methionine + h(+)
"selenocysteine Se-methyltransferase"
"selenocysteine se-methyltransferase"