The following table contains a list of the amino acid 1 and two letter codes.
Amino Acid | 3-Letter | 1-Letter |
---|---|---|
Alanine | Ala | A |
Arginine | Arg | R |
Asparagine | Asn | N |
Aspartic acid | Asp | D |
Cysteine | Cys | C |
Glutamic acid | Glu | E |
Glutamine | Gln | Q |
Glycine | Gly | G |
Histidine | His | H |
Isoleucine | Ile | I |
Leucine | Leu | L |
Lysine | Lys | K |
Methionine | Met | M |
Phenylalanine | Phe | F |
Proline | Pro | P |
Serine | Ser | S |
Threonine | Thr | T |
Tryptophan | Trp | W |
Tyrosine | Tyr | Y |
Valine | Val | V |
Additional codes for amino acids coded by unusual translations:
Amino acid | 3-Letter | 1-Letter |
---|---|---|
Selenocysteine | Sec | U |
Pyrrolysine | Pyl | O |
Additional codes for ambiguous residues in protein sequences:
Ambiguous Amino Acids | 3-Letter | 1-Letter |
---|---|---|
Asparagine or aspartic acid | Asx | B |
Glutamine or glutamic acid | Glx | Z |
Leucine or Isoleucine | Xle | J |
Unspecified or unknown amino acid | Xaa | X |