Primary structure

Definition

Primary structure is the unique sequence of amino acids in a polypeptide chain. This sequence determines the protein's final 3D shape and its specific function.

5 Must Know Facts For Your Next Test

1. The primary structure of a protein is determined by the gene encoding it.
2. A change or mutation in even one amino acid can drastically affect a protein's function.
3. Peptide bonds link amino acids together in the primary structure.
4. The primary structure dictates higher levels of protein organization like secondary, tertiary, and quaternary structures.
5. Techniques like sequencing can be used to determine the primary structure of proteins.

Review Questions

• What type of bond links amino acids together in the primary structure?
• How can mutations affect a protein’s primary structure?
• Why is the primary structure critical for determining a protein's final shape?

Related terms

secondary_structure: The local folding of the polypeptide chain into alpha helices or beta sheets stabilized by hydrogen bonds.

tertiary_structure: The overall three-dimensional shape of a single polypeptide chain, resulting from interactions between side chains (R groups).

quaternary_structure: The arrangement and interaction of multiple polypeptide subunits in a multi-subunit protein complex.