In biochemistry, the primary structure of a biopolymer,
such as a polynucleotide[?], polypeptide or protein is the linear sequence of its
contituent nucleic acid or amino acid residues.
The structural information in a primary structure is mostly the identity and
relative location along the biopolymer backbone of the individual
monomer sidechains[?]. At the atomic level, very few types of
dihedral angles[?] are specified at this level of structure. Nor are many
non-bonded interatomic contacts specified.
However, the nature of nearly all of the covalent bonds
and of many of the bond angles[?] are implied at the level of primary
structure based on the structural invariants inherent in the monomers
involved, and therefore the primary structure is rich with information.
The primary structure of a biomolecule is strongly correlated with its
biological function. With very rare exceptions, a biopolymer's biochemical
role can be uniquely identified with the primary sequence alone.