Mass spectrometry target identification

Additionally it has been our experience that mass spectrometry as a routine detection/identification technique for bacteria is not well received by microbiologists and clinicians who prefer less expensive, less complicated approaches to bacterial typing and identification, such as methods based on polymerase chain reaction (PCR) and enzyme-linked immunosorbent assays (ELISA). For that reason we have adapted our MS approach to serve as a means of biomarker discovery that feeds candidate proteins or leads into development as PCR targets or other immunoassay techniques. 

Warscheid, B. Fenselau, C. A targeted proteomics approach to the rapid identification of bacterial cell mixtures by MALDI mass spectrometry. Proteomics 2004, 4, 2877-2892. 

Lewis TS et al. Identification of novel MAP kinase pathway signaling targets by functional proteomics and mass spectrometry. Mol Cell 2000 6 1343-1354. 

Flowever, the object being analyzed has to be removed from the tissues. Thus, information about the distribution of the target in the organism or in the cells is inevitably lost. What is now needed is a technology to acquire information about the distribution of the biomolecule simultaneously with its identification. The method used for this purpose, called imaging mass spectrometry (IMS), is as follows. The tissue sample is cut into thin slices, and a matrix that assists the ionization of macromolecules is spread onto these slices. The macromolecules are then ionized by a scanning laser, and the generated ions are detected and analyzed by MS.1... 

B. Warscheid and C. Fenslau. A Targeted Proteomics Approach to the Rapid Identification of Bacterial Cell Mixtures by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry. Proteomics, 4(2004) 2877-2892. 

Structure elucidation of semiochemicals by modern NMR-techniques (including HPLC/NMR) is often hampered by the very small amounts of available material and problems in the isolation of pure compounds from the complex mixtures they are embedded in. Thus, the combination of gas chromatography and mass spectrometry, GC/MS, is frequently the method of choice. Determination of the molecular mass of the target compound (by chemical ionisation) and its atomic composition (by high resolution mass spectrometry) as well as a careful use of MS-Ubraries (mass spectra of beetle pheromones and their fragmentation pattern have been described [27]) and gas chromatographic retention indices will certainly facihtate the identification procedure. In addition, the combination of gas chromatography with Fourier-transform infrared spec-... 

Pulsed ultrafiltration MS (PUF-MS) represents an inline high throughput affinity screening method with a variety of potential uses in the discovery and development of pharmaceuticals [22]. The in-line combination of solution-phase equilibration, ultrafiltration, and electrospray liquid chromatography mass spectrometry (LC-ESI-MS) facilitates the identification of high affinity target-specific... 

Selection-independent analysis In this case, library analysis occurs strictly after and apart from the library selection experiment. Typically, what this means is that the solution resulting from a library is analyzed by HPLC or HPLC-mass spectrometry (HPLC-MS), and compared with the chromatographic trace obtained for an identical library prepared in the absence of target. This provides an internal control for self-selection processes and (hopefully) allows direct identification library members undergoing enhancement through visual inspection. If selfselection is the goal, one simply compares HPLC traces of libraries at different time points. 

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