Question

How does pH change protein structure?

Answer 1

Hint: We know that proteins are polymers of alpha amino acids and they are linked to each other by the peptide bond. Proteins are classified into fibrous proteins and globular proteins.

Complete step by step answer:
Let’s discuss the denaturation of proteins to understand the effect of pH on the structure of protein. We know that, in a biological system proteins found with unique biological activity and 3D structure are termed as native protein. When a protein in the native form, subjected to physical changes like change of temperature, change of pH, the hydrogen bonds get disturbed and this results in the unfolding of globules and the helix structure gets uncoiled. Due to this, the biological activity of proteins loses. This phenomenon is termed as denaturation of proteins. During denaturation, tertiary and secondary structure of proteins are destroyed but primary structure remains intact.
Let’s discuss some examples of denaturation of protein. The egg coagulation while boiling is an example of denaturation. The curdling of milk caused by the formation of lactic acid by the bacteria present in milk is another example of denaturation.

Additional Information:
Fibrous protein is the protein in which polypeptide chains run parallel and held together by disulphide and hydrogen bonds. For example, keratin, myosin etc.
In globular protein, polypeptide chains coil around to result in a spherical shape. For example, insulin, albumin etc.

Note: It is to be noted that denaturation of protein is an irreversible process that means, once the structure of protein is lost, it cannot be regained. There are some disadvantages of denaturation of proteins such as it can cause disruption in the activity of the cell which may lead to death.