Exploring the Potential of Molecular Spectroscopy for the Detection of Post-translational Modifications of a Stressed Biopharmaceutical Protein

Proteins are biomolecules that consist of sequences of amino acids (primary structure) which can further interact and cause the backbone to fold into more complex arrangements (secondary and tertiary structures). Any chemical alterations of the molecules after the translation of the messenger RNA code into a protein primary sequence are known as posttranslational modifications (PTMs). PTMs may affect the protein's functionality; thus it is necessary to identify them. PTMs of particular interest to the pharmaceutical industry include deamidation, oxidation, deglycosylation and isomerization, which may occur due to environmental stressors. However, they have proved challenging to identify quickly. Electronic and vibrational spectroscopies have proved valuable tools for studying higher-order structure and stability of proteins.