Please help me get the right answer and understanding Thank

Please help me get the right answer and understanding. Thank you.

Compare and contrast tertiary and quaternary Structure. Include at least two ways they are similar and two ways they are distinct.

Solution

Answer:

24. Tertiary structure:

The tertiary protein structure is a spatial conformation additional to the secondary structure in which the alpha-helix or the beta-sheet folds itself up. The forces that keep the tertiary structure generally are interactions between the –R groups of the amino acids and between other parts of the protein and water molecules of the solution.

The main types of tertiary structure of proteins are the globular proteins and the fibrous proteins.

Quaternary structure:

The quaternary protein structure is the spatial conformation due to interactions among polypeptide chains that form the protein.

Only those proteins made of two or more polypeptide chains have quaternary structure. Insulin (two chains), hemoglobin (four chains) and the immunoglobulins (antibodies, four chains) are some examples of protein having quaternary structure.

Similarities:

1. Disruptions in both tertiary and quaternary structures are often reversible.

2. All the interactions that occur in tertiary level also occur in quaternary level.

Difference:

1. Tertiary structure is more stable as compared to the quaternary structure.

2. Tertiary structure results from a large number of non-covalent interactions between amino acids, whereas quartenary structure arises due to non-covalent interactions that bind multiple polypeptides into a single, larger protein.