The IUPAC code
==============

The International Union of Pure and Applied Chemistry (IUPAC_) defined
the standard code for representing protein or DNA sequences.

Nucleic IUPAC Code
------------------

======== =================================
**Code**     **Nucleotide**
======== =================================
   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)
======== =================================


Peptidic one and three letters IUPAC code
-----------------------------------------

============  =============  =======================================
**1-letter**  **3-letters**          **Amino acid**    
============  =============  =======================================
   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
============  =============  =======================================

.. _IUPAC: http://www.iupac.org/