Post-translational modifications (PTMs) are chemical modifications made to proteins that regulate activity, localization and interaction of proteins with other cellular molecules. It has been discovered that the human genome comprises of 20-25,000 genes however it is estimated that the human proteome comprises of over 1 million proteins. PTMs make it possible for a single gene to encode multiple proteins and is therefore the key to proteome complexity. Some of the most prevalent PTMs are phosphorylation, ubiquitination, glycosylation, s-nitrosylation, SUMOylation, disulphide bond, lipidation, methylation, hydroxylation and acetylation. Phosphorylation is addition of a phosphate group to the side chain of serine, threonine or tyrosine from a high energy donor molecule (ATP). Enzyme kinase catalysed this reaction.
- ↑ 1.Jensen O. N. (2004) Modification-specific proteomics: Characterization of post-translational modifications by mass spectrometry. Curr Opin Chem Biol. 8, 33-41.
- ↑ Thermofisher.com. (2018). Phosphorylation | Thermo Fisher Scientific - MY. [online] Available at: https://www.thermofisher.com/my/en/home/life-science/protein-biology/protein-biology-learning-center/protein-biology-resource-library/pierce-protein-methods/phosphorylation.html [Accessed 23 Oct. 2018].