Two Amino Acids That are Found in Some Proteins Due

Question

Two amino acids that are found in some proteins due to exceptions in the universal genetic code are
A)pyrrolysine and selenocysteine.
B)lysine and selenocysteine.
C)pyrrolysine and cysteine.
D)lysine and cysteine.

Accepted Answer

Pyrrolysine and selenocysteine are the two amino acids that are exceptions to the universal genetic code. Pyrrolysine is found in some archaea and is encoded by the UAG codon, which is typically a stop codon. Selenocysteine is found in both bacteria and eukaryotes and is encoded by the UGA codon, which is also typically a stop codon.