Question

explain the mechanism how the double distilled water may denatured the tertiary structure of protein ?

Answer 1

Mechanism of the double distilled water may denatured the tertiary structure of protein:-

Protein tertiary structure is the 3D shape of a protein. The tertiary structure will have a single polypeptide chain "backbone" with one or moreprotein secondary structures, the protein domains. Amino acid side chains may interact and bond in a number of ways.

Proteins , which are amphoteric in nature, act as an anion or a cation depending on the pH of the solution. At some definite pH the positive and negetive charges are exactly balenced and molecule will not migrate in the electric field. this condition is called iso electric point and at this pH it is most readily precipitated.The amphoteric nature of protein is due to the presence of large number of acidic and basic group in amino acid group.

All proteins are opically active and may be coagulated or precipitated from aqueous solution by heat, the addition of acids, alkalis,salts organic solvents miscible with water . proteins in this precipitated state are said to be denatured, and the process of reaching this state ,denaturation, occurs most readily near the isoelectric point. Denaturation is now believed to be the rasult of changes in conformation or unfolding of protein molecule.

Surfaces naturally charge to form a double layer. In the common case when the surface charge-determining ions are H⁺/OH⁻, the net surface charge is affected by the pH of the liquid in which the solid is submerged.

In duble distilled water H+ and OH- ion remain equal that is neigher acidic nor basic and migration of anion and cation does not takes place and denaturation takes place.