Plasma desorption mass spectrometry proteins

New methods use combined HPLC/Mass spectrometry to identify modified amino acids. Purified recombinant human insulin-like growth factor separated into two peaks on reverse phase HPLC (Cl 8 column/acidified water) even though other methods indicated it was completely pure. Plasma desorption mass spectrometry of the individual peptides detected a single methionine sulfoxide molecule that was sufficient to decrease the hydrophobicity of the whole protein significantly. Most of the oxidation occurred when the secreted fusion protein was cleaved with hydroxylamine under not strictly anaerobic conditions, but about 5% occurred during die . coli fermentation. 

Sundqvist B, Roepstorff P, Fohlman J, Hedin A, Hakansson P, Kamensky M, Lindberg M, Salehpoour M, Save G (1984) Molecular Weight Determinations of Proteins by Californium Plasma Desorption Mass Spectrometry. Science 226 696... 

Plasma Desorption Mass Spectrometry of Peptides and Proteins... 

Nielsen, P. F., Klarskov, K., Hojrup, P., and Roepstorff, P. (1988) Optimization of sample preparation for plasma desorption mass spectrometry of peptides and proteins. Biomed. Environm. Mass Spectrom. IS, 305-310. 

Roepstorff, P. (1989) Plasma desorption mass spectrometry of peptides and proteins. Acc. Chem. Res. 22, 421-427. 

Roepstorff P, Nielsen PF, Klarskov K, Hojrup P. Applications of plasma desorption mass spectrometry in peptide and protein chemistry. Biomed Environ Mass Spectrom. 1988 16 9-18. 

The cross-reactivity between various fruits and different pollen allergens is a well-known fact and has already been studied in the 80s of the last century [19,20] using radioallergosorhent tests (RASTs). One of the first pollen allergens characterized by mass spectrometry is betv 1, the major birch pollen allergen [21]. Plasma desorption mass spectrometry (PD-MS) was used to confirm the primary structures of the intact purified protein, of all potential isoforms and some selected proteolytic peptides and to invesfigate any possible posttranslational modifications. 

A. Tsarbopoulos, M. Karas, K. Strupat, B. N. Pramanlk, T. L. Nagabhushan, and F. Hillen-kamp, Comparative mapping of recombinant proteins and glycoproteins by plasma desorption and matrix-assisted laser desorption/ionization mass-spectrometry, Anal. Chem., 66 (1994) 2062-2070. 

Until 1988, the mass spectrometric analysis of peptides and proteins was difficult. Some results were achieved using (continuous-flow) fast-atom bombardment (FAB) and Cf plasma desorption. The major breakthrough in the characterization of proteins by mass spectrometry (MS) is due to the introduction of matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) in 1988. Currently, peptides and proteins form the compound class most intensively studied by MS. This is primarily due to the prominent role ESI-MS and MALDI-MS play in the field of proteomics. 

Spectrometric Analysis. Remarkable developments in mass spectrometry (ms) and nuclear magnetic resonance methods (nmr), eg, secondary ion mass spectrometry (sims), plasma desorption (pd), thermospray (tsp), two or three dimensional nmr, high resolution nmr of soHds, give useful stmcture analysis information (131). Because nmr analysis of or N-labeled amino acids enables deterrnination of amino acids without isolation from organic samples, and without destroying the sample, amino acid metaboHsm can be dynamically analyzed (132). Protein metaboHsm and biosynthesis of many important metaboHtes have been studied by this method. Preparative methods for labeled compounds have been reviewed (133). 

Mass spectrometry currently has assumed a central role in protein sequencing. This development has been possible with the introduction of two highly sensitive ionization techniques electrospray ionization (ESI) and matrix-assisted laser desorption and ionization (MALDI) and the advent of improved instrumentation capable of high-mass and high-sensitivity detection. Currently, biopolymers with a molecular mass over 100,000 Da are analyzed routinely. In the past, fast atom bombardment (FAB) [6,7] and Cf plasma desorption (PD) ionization [8] also played a limited role in protein sequencing. Mass spectrometry now has assumed... 

Several mass spectrometric techniques including fast atom bombardment (FAB), plasma desorption (PD), matrix-assisted laser desorption/ionization (MALDI), and electrospray (ES) mass spectrometry (MS) are presently available for the analysis of peptides and proteins (Roepstorff and Richter, 1992). Of these techniques, mainly PDMS has gained footing in protein laboratories because the instrumentation is relatively cheap and simple to operate and because, taking advantage of a nitrocellulose matrix, it is compatible with most procedures in protein chemistry (Cotter, 1988 Roepstorff, 1989). Provided that the proper care is taken in the sample preparation procedure most peptides and small proteins (up to 10 kDa) are on a routine basis amenable to analysis by PDMS. Molecular mass information can be obtained with an accuracy of 0.1% or better. Structural information can be gained by application of successive biochemical or chemical procedures to the sample. 

Becker, J. Su., Mounicou, S., Zoiiy, M. V., Becker, J. S., Lobinski, R (2008) Analysis of metal-binding proteins separated by non-denaturating gel electrophoresis using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Talanta, 76, 1183-1188. 

Sud M, Fahy E, Cotter D, et al. LMSD LIPID MAPS structure database. Nucleic Acids Res. 2007 35 D527-D532. Tajima Y, Ishikawa M, Maekawa K, et al. Lipidomic analysis of brain tissues and plasma in a mouse model expressing mutated human amyloid precursor protein/tau for Alzheimer s disease. Lipids Health Dis. 2013 12 68. Woods AS, Jackson SN. Brain tissue lipidomics direct probing using matrix-assisted laser desorption/ ionization mass spectrometry. AAPS J. 2006 8(2) E391-395. 

Figure 1.13 Selected analytical techniques used for metallomics studies. ICP-OES, inductively coupled plasma optical emission spectroscopy, ICP-MS, inductively coupled plasma mass spectrometry LA-ICP-MS, laser ablation ICP-MS XRF, X-ray fluorescence spectroscopy PIXE, proton induced X-ray emission NAA, neutron activation analysis SIMS, secondary ion mass spectroscopy GE, gel electrophoresis LC, liquid chromatography GC, gas chromatography MS, mass spectrometry, which includes MALDI-TOF-MS, matrix-assisted laser desorption/ ionization time of flight mass spectrometry and ESI-MS, electron spray ionization mass spectrometry NMR, nuclear magnetic resonance PX, protein crystallography XAS, X-ray absorption spectroscopy NS, neutron scattering.

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