Question

Based on the seminal works on proteins folding, distill three take-home messages that are most likely to guide proteins to fold into their native and functional structures?

Answer 1

Primary structure of proteins have to fold in to secondary/tertiary/ quarternery forms to enter in to functional state. primary protein structure is not a functional form. There are many forces operating, which makes the protein fold in a specific manner. These are :

1. Distribution of hydrophilic and hydrophobic amino acids is important in determining the shape. This is because the cells have a lot of water and hydrophobic chains tend to cluster in the interior of the protein molecule, exposing the hydrophilic or polar amino acid to the exterior. That is why hydrophobic and hydrophilic interactions between the amino acids are important in determining the shape of the protein.

2.Interaction of the polar amino acids with the aqueous solution present around also decides the shape of the protein. Polar amino acids can dissolve in water and develop hydrogen bonds with water.

3. Weak bonds developing between amino acids of a polypetide and their side chains , such as hydrogen bonds, ionic bonds and van der waals bonds too are important in maintaining the structure of proteins. These bonds though weak individually, collectively they are strong to maintain the shape of the protein molecule. So , the arrangement of amino acids in the polypeptide chain is important in deciding all these bonds and hence maintaining the shape of the protein molecule.

Bonds formed between the amino acids, the order of amino acids and water present around are all important in maintaining the protein structure.