Proteomics is the large-scale study of proteins produced in a given organism or cellular system. By observing changes in expression, co-translational and post-translational modifications, and interactions, we can gain a better understanding of an organism’s cellular processes.
Taking advantage of advances in mass spectrometry (mass accuracy, sensitivity, resolution), we are able to identify the protein(s) in a given sample, whether it be a complex mixture or a highly purified sample.
To do this, we employ a “Bottom-up” approach, whereby protein samples are enzymatically digested (primarily by Trypsin) into smaller peptides. These peptides are then chromatographically separated and detected by MS. The peptides are further fragmented in a tandem mass spectrometry experiment and the resulting data is later matched against a protein sequence database.
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