Sequential Detergent Extraction Prior to Mass Spectrometry Analysis

Sequential detergent extraction of proteins from eukaryotic cells has been used to increase proteome coverage of 2D-PAGE. We have adapted sequential detergent extraction for use with the high-throughput non-electrophoretic proteomics method of liquid chromatography and electrospray ionisation tandem mass spectrometry. This method of extraction yields comprehensive proteomes that include up to twice as many membrane proteins as other published methods. Two thirds of these membrane proteins have more than one transmembrane domain and many of these have multiple transmembrane domains. Since sequential detergent extraction (SDE) separates proteins based upon their physicochemistry and sub-cellular localisation, this method also provides useful data about cellular localisation.