Final answer:
The sequence VAL-LYS-GLY represents the primary structure of a protein, not the quaternary structure. The primary structure is the sequence of amino acids, whereas quaternary structure refers to a complex of multiple polypeptide subunits, such as in hemoglobin.
Step-by-step explanation:
The sequence described, VAL-LYS-GLY, represents the primary structure of a protein, which is the linear sequence of amino acids connected by peptide bonds in a polypeptide chain. The primary structure is the simplest level of protein structure, and it alone does not form a functional protein. For a protein to achieve its functional form, it must undergo folding and interactions that lead to higher-order structures, such as secondary, tertiary, and quaternary structure.
The quaternary structure refers to the complex formed by the assembly of multiple polypeptide chains, often called subunits, into a single functional biomolecule. It is characterized by the arrangement and interactions of subunits, which can be stabilized by non-covalent interactions and sometimes by disulfide bonds. An example of a protein with a quaternary structure is hemoglobin, which is composed of four subunits and functions in oxygen transport in the blood.
Therefore, the primary sequence VAL-LYS-GLY does not exhibit quaternary structure. Quaternary structure is related to the assembly of distinct polypeptides, whereas the given sequence is a part of a single polypeptide chain, and additional folding and association with other polypeptide chains would be required to achieve quaternary structure.