Deamidation Detection of Protein Post-Translational Modification

Post-translational modification (PTM) refers to the chemical modifications that occur after protein translation. These modifications can influence the activity, stability, affinity, half-life, and intracellular localization of the protein.

 

Deamidation is a form of PTM where the protein loses an amide group (usually by removing the amide group on the amino acid side chain) after translation. This change might affect the protein's structure, localization, function, and its interaction with other molecules. For instance, deamidated proteins play a regulatory role in processes like neurotransmitter release and cell signal transduction. Thus, accurately detecting and understanding deamidation modifications is crucial for revealing cellular mechanisms.

 

Traditionally, detecting deamidation modifications was challenging due to the often subtle and unstable nature of these modifications. However, with advancements in mass spectrometry, especially the use of liquid chromatography-tandem mass spectrometry (LC-MS/MS), researchers can now identify and quantify these modifications more precisely. By accurately measuring the mass change in the protein or peptide, the occurrence of a deamidation event can be inferred.

 

Moreover, combining specific enzymatic cleavage strategies and enrichment methods, such as using specific antibodies to enrich deamidated proteins or peptides, can enhance the sensitivity and specificity of detection. The combination of these techniques allows researchers to detect trace amounts of deamidation modifications in complex biological samples, such as cellular extracts or body fluids.