Mass spectrometry for protein identification and the study of post translational modifications.

Mass spectrometry is a powerful tool for the structural characterization of proteins. The development of a large number of analytical strategies based on different mass spectrometric techniques has established mass spectrometry as an indispensable technology to interpret the information encoded in the genome. This manuscript intends to provide a rapid view of principles and instrumentation in mass spectrometry-based proteomics, together with a description of the basic features and limits of the analysis of post translational modifications by mass spectrometry. The application of one of the available mass spectrometry technologies for protein identification to a multi-protein complex isolated in a specific functional context is reported. The identification of a phosphorylation site on a single, purified protein is also illustrated as an example.