N5-methyltetrahydropteroyltriglutamate-homocysteine methyltransferase
Selenocystathionine + Water → Ammonia + Pyruvic acid + Selenohomocysteine
Adenosine triphosphate + Selenomethionine + tRNA(Met) → Adenosine monophosphate + Pyrophosphate + Selenomethionyl-tRNA(Met)
Selenomethionine + Water → 2-Ketobutyric acid + Ammonia + methylselenol
5-Methyltetrahydropteroyltri-L-glutamate + Selenohomocysteine ↔ Selenomethionine + Tetrahydropteroyltri-L-glutamate
O-succinyl-L-homoserine + Selenocystathionine ↔ Selenocysteine + Succinic acid
Acetylhomoserine + Selenocysteine ↔ Acetic acid + Selenocystathionine
Methylselenic acid + Hydrogen Ion + NADPH → NADP + Water + methylselenol
Se-Methylselenocysteine + Water → Ammonia + Pyruvic acid + methylselenol