6.Proline(Pro)
The role of proline was studied for the first time in in vitro refolding of bovine carbonic anhydrase. Proline inhibited bovine carbonic anhydrase aggregation and enabled the protein to return to its native structure. It was proposed that proline acts as a protein-folding chaperone due to the formation of an ordered, amphipathic supramolecular assembly [50]. Later, proline was found to prevent aggregation during hen egg-white lysozyme refolding. Also proline has been used during refolding of arginine kinase [32] and aminoacylase [51]. Proline inhibits protein aggregation by