Some influences that can alter the biological activity of proteins

Some influences that can alter the biological activity of proteins 

A number of different influences can denature or otherwise modify proteins, rendering them less active/inactive. As all protein products are marketed on an activity basis, every precaution must 

Partial/complete protein denaturation Covalent alterations Hydrolysis Deamidation Imine formation Racemization Oxidation 

A number of different molecular mechanisms can underpin the loss of biological activity of any protein. These include both covalent and non-covalent modification of the protein molecule, as summarized in Table 6.5. Protein denaturation, for example, entails a partial or complete alteration of the protein s three-dimensional shape. This is underlined by the disruption of the intramolecular forces that stabilize a protein s native conformation, namely hydrogen bonding, ionic attractions and hydrophobic interactions (Chapter 2). Covalent modifications of protein structure that can adversely affect its biological activity are summarized below. 

Oxidation Disulfide exchange Isomerization Photo decompo sition 

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