IUPAC Codes
Amino acid codes
| 1-letter | 3-letter | description |
|---|---|---|
| A | Ala | Alanine |
| R | Arg | Arginine |
| N | Asn | Asparagine |
| D | Asp | Aspartic acid |
| C | Cys | Cysteine |
| Q | Gln | Glutamine |
| E | Glu | Glutamic acid |
| G | Gly | Glycine |
| H | His | Histidine |
| I | Ile | Isoleucine |
| L | Leu | Leucine |
| K | Lys | Lysine |
| M | Met | Methionine |
| F | Phe | Phenylalanine |
| P | Pro | Proline |
| S | Ser | Serine |
| T | Thr | Threonine |
| W | Trp | Tryptophan |
| Y | Tyr | Tyrosine |
| V | Val | Valine |
| B | Asx | Aspartic acid or Asparagine |
| Z | Glx | Glutamine or Glutamic acid |
| X | Xaa | Any amino acid |
Nucleic acid codes
| code | description |
|---|---|
| A | Adenine |
| C | Cytosine |
| G | Guanine |
| T | Thymine |
| U | Uracil |
| R | Purine (A or G) |
| Y | Pyrimidine (C, T, or U) |
| M | C or A |
| K | T, U, or G |
| W | T, U, or A |
| S | C or G |
| B | C, T, U, or G (not A) |
| D | A, T, U, or G (not C) |
| H | A, T, U, or C (not G) |
| V | A, C, or G (not T, not U) |
| N | Any base (A, C, G, T, or U) |
