Building on the work that has been done in the field of genomics, proteomics is the study and quantification of all the proteins in an organism. Not only do different cells produce different proteins, but protein production varies according to time and situation, changing based on stressors and environmental factors. There are also many different post-translational modifications that proteins can undergo, such as phosphorylation, ubiquitinization, and methylation that alter a protein's structure and function. Proteomics could lead to the identification of biomarkers for disease states, such as cancer, or individualized drug therapies. The human proteome is estimated to contain between 20,000 and 25,000 unique proteins, but when considering post-translational modifications this number may be in the millions. Current techniques for identifying proteins include immunoassays and electrophoresis. However, recent studies of proteins in yeast show low levels of reproducibility and higher-output protein detection and identification methods are needed.
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