What is the tertiary structure of a protein and how is it ma

What is the tertiary structure of a protein and how is it maintained?

Solution

The three-dimensional conformation of a protein molecule is termed as the tertiary structure of protein. The alpha and the beta pleated sheets forming the secondary structure of protein are folded in the globular form to form the tertiary structure of protein. In such a way they bend and twist so that they achieve a.) maximum stability or b.) lowest energy state. The tertiary structure of protein comprises of only one polypeptide which differentiates it from quaternary structure which contains more than one polypeptide.

The tertiary structure of protein is maintained by the following interactions between alpha and beta helices:

a.)    Disulfide bonds- these are formed between the sulfhydryl group on the cysteine amino acid. These are the bridging bond

b.)    Non polar hydrophobic interaction- these are formed between the non-polar side chains

c.)     Salt bridges- these are also known as ionic interaction which is formed between the acidic amino acid and an amine group

d.)    Hydrogen bonds: these bonds are formed between various residues such as alcohol and an acid, two acids etc.