selenocysteine sec, u amino acid molecule. called the 21st proteinogenic amino acid, present in selenoproteins.

selenocysteine sec amino acid molecule called 21st proteinogenic present selenoproteins selenocystein selenium selenol enzyme selenoprotein antioxidant codon genetic code uga seleno cysteine 3d rendering atoms are represented as spheres conventional color coding hydrogen white carbon grey oxygen red nitrogen blue orange