Mass Spectrometric ( MS) Analysis of Proteins and Peptides

The human genome is sequenced and comprised of similar to 30,000 genes, making humans just a little bit more complicated than worms or flies. However, complexity of humans is given by proteins that these genes code for because one gene can produce many proteins mostly through alternative splicing and tissue-dependent expression of particular proteins. In addition, post-translational modifications (PTMs) in proteins greatly increase the number of gene products or protein isoforms. Furthermore, stable and transient interactions between proteins, protein isoforms/proteoforms and PTM-ed proteins (protein-protein interactions, PPI) add yet another level of complexity in humans and other organisms. In the past, all of these proteins were analyzed one at the time. Currently, they are analyzed by a less tedious method: mass spectrometry (MS) for two reasons: 1) because of the complexity of proteins, protein PTMs and PPIs and 2) because MS is the only method that can keep up with such a complex array of features. Here, we discuss the applications of mass spectrometry in protein analysis.

Automated summary

The human genome consists of around 30,000 genes, making humans slightly more complex than worms or flies. However, the complexity of humans mainly comes from the diverse proteins encoded by these genes, as well as the production of multiple proteins through alternative splicing and tissue-dependent expression. Post-translational modifications in proteins significantly increase the number of gene products or protein isoforms.