Proteome

Proteomics has largely been practiced through the separation of proteins by two dimensional gel electrophoresis. In the first dimension, the proteins are separated by isoelectric focusing[?], which resolves proteins on the basis of charge. In the second dimension, proteins are separated by molecular weight using SDS-PAGE. The gel is dyed with Coomassie Blue[?] or silver to visualize the proteins. Spots on the gel are proteins that have migrated to specific locations.

The mass spectrometer has augmented proteomics. Mass mapping[?] identifies a protein by cleaving it into short peptides and then deduces the protein's identity by matching the observed peptide masses against a sequence database[?]. Tandem mass spectrometry, on the other hand, can get sequence information from individual peptides by isolating them, colliding them with a nonreactive gas, and then cataloging the fragment ions produced.

See also: Proteomics