Proteins have four levels of structure: primary (amino acid sequence), secondary (local folding patterns like alpha helices and beta sheets), tertiary (overall 3D shape), and quaternary (assembly of ...

The linear sequence of amino acids within a protein is considered the primary structure of the protein. Proteins are built from a set of only twenty amino acids, each of which has a unique side chain.

When molecules bind or dissociate, the change in their primary, secondary, tertiary and/or quaternary structure changes the hydration shell ... binding from single metal ions to the formation of ...