Physiological proteomics of gram-positive bacteria

A combination of gel-based and gel-free proteomics has been used to visualize the entire proteome of bacteria. In the presentation it will be shown that gel-based proteomics is still a valuable tool to cover the cytosolic and extracellular proteins and to visualize proteins newly synthesized in the cell. Low abundance proteins, however, can only be identified by gel-free proteomics. For the membrane and cell surface-associated proteomes, however, gel-free approaches are necessary to identify the proteins. Using a reasonable combination of gel-based and gel-free approaches almost 70 to 80 % of the proteins expressed under specific circumstances can be detected and quantified.