Newly synthesized proteins must fold to unique three dimensional structures to become functionally active. The native fold of protein is encoded in its amino acid sequence. One of the big challenges of modern science is to uncover the mechanism of protein folding. How the protein folds to a three dimensional structure is still unknown. Anfinsen et al suggested that primary amino acid sequence of proteins has all the information to fold into a native conformation. However, the key to proper folding of proteins lie in the ability of hydrophobic amino acid side.