Chapter 21, Problem 15A

Interpretation Introduction

Interpretation:

The tertiary structure of proteins and differences between the secondary and tertiary structures needs to be explained.

Concept introduction:

Protein- proteins are polymer of the amino acids and they are joined together with a peptide linkage.

The different classes of proteins based on the arrangements of the amino acids.

The tertiary structure of a protein is a complex form of protein.

Answer to Problem 15A

The tertiary structure of a protein is formed by the complex rearrangement of the secondary protein.

Explanation of Solution

The tertiary structure of proteins formed with complex folding of the amino acid chain. The polypeptides chains are interlinked with each other and form a coiled tertiary structure of a protein.

The structure is stabilized by the hydrogen bonds, disulfide linkages, van der Waals, and electrostatic forces of attraction present between the amino acids.

Difference between the secondary and tertiary structure of proteins-

Secondary structure	Tertiary structure
Formed by the folding of the peptide chain into alpha and beta-sheets	The structure is formed by further coiling of the secondary structure.
Composed by the peptide and hydrogen bonds.	Encompasses disulfide linkage, and hydrogen bonding.
From fibrous proteins used to form collagen, elastin, myosin, etc.	Includes enzymes, hormones, and globulin, etc.
This structure is twisted and present in the form of pleated folds.	These complex type proteins present in three-dimension shape.
Peptide linkage and hydrogen bond interaction is present.	Peptide and disulfide linkage present with hydrogen bonds.

Conclusion

The complex three-dimensional structures are the basic structure of the tertiary protein. The peptide linkage and folding are found in secondary and tertiary structure. The secondary and tertiary structures of proteins are form different types of proteins like fibrous and globular proteins.