How do changes in pH affect protein structure Which levels o

How do changes in pH affect protein structure? Which levels of protein structure will be affected by a change in pH?

Solution

With thechanges in the pH the interactions between the side chains in the protein molecule changes. The two important interactions which include the hydrogen bonding and salt bridges changes with pH. This plays a prominent role determining the protein structure. Consider in case of Serine and Lysine. The alcoholic group of the serine indulges in hydrogen bond formation with the amine group of lysine, any changes in pH, alters the hydrogen bond stability and results in chnage in the shape and structure of protein. In addition the salt bridges which are the ionic bonds formed between the oppositely charged side chains of amino acids, for example the amino group of aspartic acid and the carboxylic group of lysine, the salt bridge present between the two molecule disappears with the changes in pH as there will a change in the ions of the side chains. Secondary strucure of the protein strongly depends on pH; hence with the changes in pH secondary structure changes.