After specific proteins are identified for further research, they are excised from the gel and treated with a succession of enzymes that cut amino acid chains into short polypeptides about 5-10 amino acids in length.

The polypeptide fragments for each protein are then separated by capillary electrophoresis and analyzed using rapid-throughput mass spectrometry. At this point, we know the amino acid sequence of the polypeptide fragments, their mass, as well as post-translational modifications that occured such as glycosylation and phosphorylation.

Genomics Enters the Picture

Once the amino acid sequence is determined for each protein excised from the gel, these protein “fingerprints” can be checked against existing protein and DNA sequence databases. Incyte’s LifeSeq® database is essentially a vast library of predicted peptide (protein) sequences. When a matching sequence is found, it can be used to annotate and help predict the full amino acid sequence of the protein. This is where the power of genomics and proteomics comes together to create a “best of both worlds” discovery platform.