Characterization and understanding of protein expression in biological systems naturally follows from the mapping of organism genomes. At this facility we are involved in many proteomics projects in core and collaborative research and we provide service for others who require proteomics data. The Resource supports major research projects in type 1 diabetes (T1DM), acquired immune deficiency syndrome (AIDS), skin cancer, breast cancer, and many other NIH-funded projects both at Washington University and throughout the United States.
Recent developments such as electrospray ionization (ESI) and matrix-assisted laser desorption ionization (MALDI) have made mass spectrometry an important tool in the emerging field of proteomics. Most of the proteomics work is done at this facility employs high performance liquid chromatography coupled to an ESI or nanoESI ion source that fronts an ion trap or hybrid mass spectrometer. For complex mapping research like the Muscle Mitochondrial Proteome Project, we use both the ABI 4700 TOF/TOF Proteomics analyzer and the Thermo LTQ-FT. For the Diabetogenic Peptide Project we employ ion trap or hybrid instruments. The resulting data is analyzed using Mascot, Sequest, and X!Tandem database searching algorithms to generate lists of peptides and proteins. Extended analysis is pursued using software developed commercially, in house (Software Development,) or available from other academic groups (for example, the software available from Proteome Commons at the University of Michigan).
A Bruker 12-T FTMS system was installed in the Danforth Laboratory in June of 2009. This instrument allows us to develop methods for studying ensembles of posttranslational modification (PTM) in large protein fragments using top-down methods. The instrument will incorporate both ECD and ETD as well as an Advion Nanomate and a UPLC. The ultimate goal is to map out the distribution of states of phosphorylation and other PTM during a variety of cellular processes that impact human health.
King JB, Gross J, Lovly CM, Rohrs H, Piwnica-Worms H, Townsend RR. Accurate mass-driven analysis for the characterization of protein phosphorylation. Study of human Chk2 protein kinase. Anal. Chem. 78 2171-81 (2006).