Thioredoxin reductase

Thioredoxin Reductase (TR, TrxR) are the only known enzymes to reduce thioredoxin (Trx). All known kingdom of organisms contain thioredoxin reductase. Two types thioredoxin reductase evolved independently, prokaryotes, archia and most plants have one type and higher eukaryotes and some plants contain a different type TR which contains selenocysteine.