As a discipline, proteomics is defined as the large-scale analysis of
proteins in a particular biological system at a particular moment in
time (Pandey & Mann, 2000). Proteomics includes not only the study
of structure and function of proteins but also the analysis of protein
modifications, the interactions between them, their intra-cellular location
and the quantification of their abundance. Mass spectrometry (MS), mainly matrix-assisted laser desorption/ionization-time of flight
(MALDI-TOF) and electrospray-ion trap (ESI-IT) mass spectrometry, is
recognized as an indispensable tool for proteomics studies (Aebersold
& Mann, 2003). But the history of proteomics began in the 1970s with
the development of two-dimensional gel electrophoresis (2-DE),
which provided the first way of displaying thousands of proteins on a
single gel (Klose, 1975; O'Farrell, 1975). Nowadays, bioinformatics
treatment of the data has increased the scale of proteomics tools,
representing a powerful strategy for a high-throughput protein and
peptide identification and quantification.