Question

The function of a protein is dependent upon the shape into which the chain of amino acids folds. Many noncovalent interactions are responsible for maintaining the protein's shape. Assume you have isolated a protein from an organism in its proper shape, and you have treated it with an enzyme that selectively targets and breaks only the peptide bonds in the proteins. Would the protein retain its shape under these conditions?
a. Yes; once noncovalent bonding determines the shape of a protein, the peptide bonds are no longer necessary.
b. Yes; because the noncovalent interactions that determine the shape of a protein are stronger than the peptide bonds.
c. No; while the noncovalent bonds determine the shape of a protein, the peptide bonds are required to hold the amino acids together.
d. Yes; but the shape would be affected to a greater extent by changes in temperature.

Answer 1

Answer: c). No; while the noncovalent bonds determine the shape of a protein, the peptide bonds are required to hold the amino acids together.

Explanation: Peptide bonds is a type of bond that covalently joins two or more amino acid molecules through a substituted amide linkage. Peptide bond is formed by the removal of the elements of water from the alpha carboxyl group of one amino acid and the alpha-amino group of another amino acid. When two amino acids molecules are joined by peptide bond, the resulting molecule is called a dipeptide, when three amino acids molecules are linked by two peptide bonds, a tripeptide is formed. When a few amino acids are joined by peptide bonds, the structure is called an oligopeptide, when many amino acids are joined, the product is called a polypeptide.

Since the enzyme breaks the peptide bonds, it means that the protein has been broken down into its constituent amino acid, therefore the protein has lost its primary structure and therefore will no longer retain its shape.