Atom Bombardment Tandem Mass Spectrometry Research Articles

FAB-MS/MS Spectrometry in Determining the Primary Structure ofγ-Glutamyl-Containing Peptides

Positive fast atom bombardment tandem mass spectrometry (FAB-MS/MS) was applied for peptide sequencing, particularly for determining the gamma glutamyl linkage involved in metal-binding peptides such as Cadystin (γEC)3G = Cadystin A and Cadystin (γEC)2G = Cadystin B (MW 771 and 539, respectively). The fragmentation patterns between the natural gamma glutamyl peptide and the synthetic alpha glutamyl one were clearly distinguishable. FAB-MS/MS was proved to be a good method for determining these peptides, since it needed no chemical degradation and only a small amount of the peptide was needed for determination.

Metabolic activation of 1,2-dibromo-3-chloropropane: evidence for the formation of reactive episulfonium ion intermediates

The nematocide and soil fumigant 1,2-dibromo-3-chloropropane (DBCP) is a carcinogen and a mutagen and displays target-organ toxicity to the testes and the kidney. It has been proposed that both cytochrome P-450 mediated activation and glutathione (GSH) conjugation pathways are operative in DNA damage and organotropy induced by DBCP. To determine the chemical mechanisms involved in the bioactivation of DBCP and to assess a role for an episulfonium ion intermediate, the mechanism of formation of GSH conjugate metabolites of DBCP was investigated. Five biliary GSH conjugates of DBCP were isolated from rats and identified by fast atom bombardment tandem mass spectrometry: S-(2,3-dihydroxy-propyl)glutathione (I), S-(2-hydroxypropyl)glutathione (IIA), S-(3-chloro-2-hydroxypropyl)glutathione (III), 1,3-di(S-glutathionyl)propan-2-ol (IV), and 1-(glycyl-S-cysteinyl)-3- (S-glutathionyl)propan-2-ol (V). The mechanisms of conjugate formation were addressed by assessing deuterium retention in conjugates derived from [1,1,2,3,3-2H5] DBCP (D5-DBCP). GSH conjugates I, III, IV, and V displayed quantitative retention of deuterium, an observation consistent with the formation of an episulfonium ion intermediate. GSH conjugate IIA, however, retained three atoms of deuterium, thus invoking a P-450 mechanism in its genesis. The involvement of glutathione transferase (GST) and sequential episulfonium ion intermediates in the formation of metabolites I, III, and IV was demonstrated in vitro. Upon incubation of DBCP with GST, metabolites I, III, and IV were identified by tandem mass spectrometry and were found to arise with quantitative retention of deuterium when D5-DBCP was employed as a substrate. An additional GSH conjugate, 1,2,3-tri(S-glutathionyl)propane (VI), was observed as the major metabolite in incubations of GST with DBCP. When the incubations of DBCP with GST were performed in H2(18)O, metabolite I incorporated two atoms of 18O, and metabolites III and IV incorporated one atom of 18O. The ability of GST to catalyze the formation of the four GSH conjugates observed in vivo, with quantitative retention of deuterium and incorporation of 18O from H2(18)O, may be rationalized by a mechanism invoking the initial formation of S-(2-bromo-3-chloropropyl)glutathione. Rearrangement of this unstable conjugate via several reactive episulfonium ions, with either hydrolysis by water or alkylation of GSH at various stages, would account for the pattern of metabolites and their status of isotopic enrichment observed under various incubation conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

FAB-MS/MS spectrometry in determining the primary structure of .GAMMA.-glutamyl-containing peptides.

Positive fast atom bombardment tandem mass spectrometry (FAB-MS/MS) was applied for peptide sequencing, particularly for determining the gamma glutamyl linkage involved in metal-binding peptides such as Cadystin (gamma EC)3G = Cadystin A and Cadystin (gamma EC)2G = Cadystin B (MW 771 and 539, respectively). The fragmentation patterns between the natural gamma glutamyl peptide and the synthetic alpha glutamyl one were clearly distinguishable. FAB-MS/MS was proved to be a good method for determining these peptides, since it needed no chemical degradation and only a small amount of the peptide was needed for determination.

Lampteromyces bioluminescence : 3. Structure of lampteroflavin, the light emitter in the luminous mushroom, L. japonicus

The structure of lampteroflavin, the light emitter in the luminous mushroom ( Lampteromyces japonicus), was determined to be a new riboflavin α- d-riboside, its structure being elucidated on the basis of fast atom bombardment tandem mass spectrometry, NMR, and CD studies.

Synthesis and characterization of isotopically‐labelled cysteine‐ and glutathione conjugates of methylisocyanate

AbstractFour isotopically labelled analogs of S‐(N‐methylcarbamoyl)glutathione (SMG), the glutathione conjugate of methylisocyanate, and three isotopically‐labelled derivatives of S‐(N‐methylcarbamoyl)cysteine (SMC), the corresponding cysteine adduct, have been prepared by reaction of glutathione and cysteine, respectively, with [1‐13C]‐, [3‐13C]‐, [3‐14C]‐ or [3,3,3‐2H3]methylisocyanate. The latter species, which served as key intermediates in the syntheses, were obtained either by reaction of [1‐13C]acetylchloride with sodium azide (to give [1‐13C]methylisocyanate), or by reaction of silver cyanate with iodomethane labelled with 13C, 14C or deuterium (to give the methyl‐substituted compounds). Condensation of labelled methylisocyanate with glutathione or cysteine proceeded smoothly and in high yield in aqueous acetonitrile solution, and afforded the target conjugates in high isotopic purity. The structures of the products were confirmed by fast atom bombardment tandem mass spectrometry (FAB/MS/MS) and by 1H‐ and 13C‐NMR spectroscopy.

Location of Seven Post-translational Modifications in Rabbit Elongation Factor 1α Including Dimethyllysine, Trimethyllysine, and Glycerylphosphorylethanolamine

Amino acid sequencing of a large number of chemical and enzymatic cleavage products of elongation factor 1 alpha purified from rabbit reticulocyte has identified seven post-translationally modified residues. Five of the modifications are methylations of lysine residues yielding dimethyllysine at residues 55 and 165 and trimethyllysine at residues 36, 79, and 318. The two remaining post-translational modifications involve the addition of ethanolamine to glutamic acid residues 301 and 374, as reported previously (Rosenberry, T. L., Krall, J. A., Dever, T. E., Haas, R., Louvard, D., and Merrick, W. C. (1989) J. Biol. Chem. 264, 7096-7099). Fast atom bombardment mass spectrometry and fast atom bombardment tandem mass spectrometry have been used to analyze peptides containing these modified residues. The analyses have determined that glycerylphosphorylethanolamine has been attached to the glutamic acid residues. An analysis of the amino acid sequence surrounding each of the three types of modification has indicated no similarities. Therefore, it seems likely that the modifying enzymes do not recognize a specific amino acid sequence but rather the three-dimensional presentation of either amino or carboxyl residues in the elongation factor 1 alpha structure.

Fast atom bombardment tandem mass spectrometry for amino acid sequence determination in tripeptides.

Mass spectral information obtained from the spectra of 26 tripeptides was carefully studied. The data were obtained from their mass, metastable ion and collisional activation spectra. On the basis of the positive ion tandem mass spectra a simple and unambiguous method for the sequence determination of amino acids in tripeptides and Y3" ions is proposed. The use of negative ion spectra for sequence determination in tripeptides is evaluated.

A New Core Tetrasaccharide Component from the Lipopolysaccharide of Rhizobium trifolii ANU 843

A second core oligosaccharide fragment has been isolated and characterized from the lipopolysaccharide (LPS) of Rhizobium trifolii ANU 843. The oligosaccharide is a tetrasaccharide composed of galactose, galacturonic acid, mannose, and 3-deoxy-D-manno-2-octulosonic acid. The mannose residue is alpha-linked to the 4-position of 3-deoxy-D-manno-2-octulosonic acid and the galacturonic acid residue is alpha-linked to the 6-position of mannose. The galactose residue, which is acetylated at the 4-position, is attached to the 4-position of mannose by an alpha-linkage. All of the aldoses are in the pyranose form. The composition of the tetrasaccharide was determined by gas-liquid chromatography of the alditol acetate derivatives of the component monosaccharides. The configuration of anomeric linkages was determined by 1H NMR spectroscopy. Fast atom bombardment-mass spectrometry (FAB-MS) was performed on acetylated, per(trideutero)acetylated and underivatized tetrasaccharide giving sequence information in addition to information on the residue which was acetylated. Similar studies were performed on the oligosaccharide after reduction with sodium cyanoborohydride and peracetylation with labeled and unlabeled acetic anhydride as before. Further linkage and sequence analysis was obtained from methylation analysis, and from electron impact mass spectrometry of the per(trideutero)acetylated oligosaccharide and from collision-induced dissociation fast atom bombardment tandem mass spectrometry using linked scans at constant B/E on the cyanoborohydride-reduced, per (trideutero)acetylated oligosaccharide. The exact location of the acetyl group was deduced from 1H NMR double resonance experiments in conjunction with mass spectrometric data.

Tandem mass spectrometry of polyglycols

Fast atom bombardment—tandem mass spectrometry has been carried out with low molecular weight samples of poly(ethylene glycol) and poly(propylene glycol). Sodium attachment ions generated from either polymer were found to be extremely stable. Decomposition could be induced only by high energy (keV) collisional activation; dissociation was minimal even for cations with 3-keV translational energy. The fragmentation that does occur can be explained by 1,4-hydrogen elimination with concurrent CO bond cleavage. Proton attachment ions, however, were found to be much less stable. These decomposed easily upon low energy collision (51 eV) to yield fragment ios which can be explained by charge-site initiation. From an analytical viewpoint, it appears that tandem mass spectrometry, combined with a desorption ionization method, is very useful for direct analysis of the chemical structure of individual components in an oligomeric mixture.

Mycotoxin Analysis by Fast Atom Bombardment Tandem Mass Spectrometry

Positive fast atom bombardment tandem mass spectrometry is demonstrated to be an effective technique for determination of crude aflatoxins and sterigmatocystin-related compounds. The molecular ion was selected by the first system and bombarded to produce characteristic daughter ions that could be used to identify mycotoxins in mixtures and with the same molecular weight.

Relation between alkali ion affinity and ionic radius ratio by means of fast atom bombardment tandem mass spectrometry

AbstractCationization of organic molecules has been studied using fast atom bombardment mass spectrometry and tandem mass spectrometric methods. The order of the A+ affinity to G (G − H + A) and AX was determined by this tandem mass spectrometric approach, where G, A and X represent glycerol, alkali metal element and halogen element, respectively. The affinity orders of most alkali halides are divided into three classes. By analogy with the ionic radius ratio rule in solid ionic crystals, this particular parameter, ionic radius ratio, was introduced to analyse the experimental results. This classification is thought to be caused by the ionic radius ratio (X−/A+). These ratios of the I, II and III classes exist between 0.657 and 1.026, 1.096 and 1.776, and 1.856 and 2.289, respectively. The ionic radius ratio plays an important role for determination of the order of alkali ion affinity.

Characterization of seven antihistamines, theirN-oxides and related metabolites by fast atom bombardment mass spectrometry and fast atom bombardment tandem mass spectrometry

We have examined the synthetic N-oxides of five ethylenediamine-type antihistamines using fast atom bombardment (FAB) mass spectrometry and FAB tandem mass spectrometry (MS/MS). Fragmentation of the protonated molecule in the normal and collisionally activated spectra appeared to be characteristic for this class of antihistamine N-oxide. Spectra were also acquired from an ethanolamine and a propylamine antihistamine N-oxide for comparison. These results were very similar to those obtained from biologically produced antihistamine N-oxides, as well as isomeric metabolites, which were readily distinguished from the N-oxides by characteristic fragmentation. In addition, a prominent ion 16 daltons lower in mass, which has been attributed to loss of elemental oxygen from the protonated N-oxide in chemical ionization mass spectral studies, was shown to be a matrix-dependent product of the solution-phase reduction of the antihistamine N-oxide to the parent antihistamine during FAB ionization. These results demonstrate that with a non-reducing matrix such as glycerol, FAB mass spectrometry and FAB MS/MS are excellent methods for the characterization of the non-conjugated antihistamine metabolites such as the N-oxides.

The use of mass spectrometry in the study of chemically-reactive drug metabolises. Application of MS/MS and LC/MS to the analysis of glutathione- and related S-linked conjugates of N-methylformamide

The S-( N-methylcarbamoyl) derivatives of glutathione, cysteine and N-acetylcysteine, the S-linked conjugates derived from a reactive metabolite of N-methylformamide (NMF), were studied in mice dosed with an equimolar mixture of NMF and deuterium-labelled NMF. Following preparation of N-benzyloxycarbonyl derivatives in aqueous media, the title conjugates were isolated, purified as their methyl esters and subjected to analysis by fast atom bombardment mass spectrometry (FAB/MS), fast atom bombardment tandem mass spectrometry (FAB/MS/MS) or thermospray liquid chromatography/mass spectrometry (TSP LC/MS). Characteristic isotope clusters in the FAB or TSP mass spectra facilitated recognition of drug metabolites, while constant neutral loss (89 u) and daughter ion scanning tandem mass spectrometry (MS/MS) experiments provided unique structural information on the conjugates of interest. It is concluded that the combined use of stable isotopes, aqueousphase derivatization and contemporary mass spectrometric techniques represents a powerful approach for the analysis of glutathione adducts and related S-linked conjugates of chemically-reactive drug metabolites.

Coupling of capillary zone electrophoresis and capillary liquid chromatography with coaxial continuous-flow fast atom bombardment tandem sectro mass spectrometry

The coaxial continuous-flow fast atom bombardment (FAB) system has proven to be very useful for interfacing capillary liquid chromatography and capillary zone electrophoresis (CZE) with sector mass spectrometry (MS). The interface can be used for the acquisition of both MS and MS—MS spectra from femtomole levels of non-volatile and/or thermally labile analytes while maintaining separation efficiencies of hundreds of thousands of plates. The use of coaxial fused-silica capillary columns to independently deliver the microcolumn effluent and th FAB matrix to the tip of the FAB probe offers the following advantages: the compositioni and flow-rates of the two liquid streams can be independently optimized; the FAB matrix does not effect the microcolumn separation process; peak broadening is minimized since the two liquid streams do not mix until they reach the tip of the FAB probe where ion desorption occurs; and, with CZE, active electrophoretic transport delivers the analytes directly to the FAB probe tip. These features combine to make this coaxial continuous flow fast atom bombardment interface particularly well suited for use with microcolumn separation methods.

Identification of some abnormal haemoglobins by fast atom bombardment mass spectrometry and fast atom bombardment tandem mass spectrometry.

The characterization of two abnormal human haemoglobins by fast atom bombardment (FAB) mapping is presented. The first variant, called 'R', exhibits a tryptic FAB map identical to that of normal haemoglobin. However, using Staphylococcus protease V8, a peptide containing the carboxyl end of the beta-chain exhibits a mass shift down to 300 mass units. This clearly indicates the deletion of the two last amino acids of the beta-chain. The second variant, called 'Grenoble', is due to two different modifications of the beta-chain. The location of the Pro----Ser exchange on peptide T5 is achieved by the collisionally activated dissociation mass analyzed ion kinetic energy spectra of the corresponding [MH]+ ion. The m/z value of that peptide indicated a supplementary acid----amide modification, which was located by amino acid sequencing using chemical methods. This work concludes with the necessity of using complementary methods for achieving rapid determinations of abnormal proteins with minute amounts.

ChemInform Abstract: Stability Trends and Fragmentation Patterns of Gaseous Yttrium Oxide Clusters Studied by Fast Atom Bombardment Tandem Mass Spectrometry

Abstract The fragmentation patterns of yttrium oxide cluster species YO+, Y2O2+, Y2O3+, Y3O4+, Y4O6+, Y5O7+, Y6O8+ and Y7O10+ were investigated at collision energies 30–110 and 170 eV by fast atom bombardment tandem mass spectrometry. The collision activated dissociation (CAD) spectra obtained revealed higher thermodynamic stability for the clusters of general formula YαO(3α−1)/2+, where a is an odd number (e.g. YO+, Y3O4+, Y5O7+, Y7O10+) which are also the preferred CAD products for all oxide clusters studied. These most stable oxides are constituted by trivalent yttrium only whereas those containing formally tetravalent yttrium YaO3a/2+, (where a is even) e.g. Y2O3+ and Y4O6+, are extremely unstable. The clusters YaO(3a−2)/2+, (where a is even) containing divalent yttrium, e.g. Y2O2+ and Y6O8+, have considerable stability but their CAD products are again the thermodynamic products YaO(3a−1)/2+. Electronic structures appear to have overriding significance in determining the thermo- dynamic stabilities of the oxide cluster species.

Stability trends and fragmentation patterns of gaseous yttrium oxide clusters studied by fast atom bombardment tandem mass spectrometry

The fragmentation patterns of yttrium oxide cluster species YO +, Y 2O 2 +, Y 2O 3 +, Y 3O 4 +, Y 4O 6 +, Y 5O 7 +, Y 6O 8 + and Y 7O 10 + were investigated at collision energies 30–110 and 170 eV by fast atom bombardment tandem mass spectrometry. The collision activated dissociation (CAD) spectra obtained revealed higher thermodynamic stability for the clusters of general formula Y αO (3α−1)/2 +, where a is an odd number (e.g. YO +, Y 3O 4 +, Y 5O 7 +, Y 7O 10 +) which are also the preferred CAD products for all oxide clusters studied. These most stable oxides are constituted by trivalent yttrium only whereas those containing formally tetravalent yttrium Y a O 3 a/2 +, (where a is even) e.g. Y 2O 3 + and Y 4O 6 +, are extremely unstable. The clusters Y a O (3 a−2)/2 +, (where a is even) containing divalent yttrium, e.g. Y 2O 2 + and Y 6O 8 +, have considerable stability but their CAD products are again the thermodynamic products Y a O (3 a−1)/2 +. Electronic structures appear to have overriding significance in determining the thermo- dynamic stabilities of the oxide cluster species.

Differentiation of isotopically labeled nucleotides using fast atom bombardment tandem mass spectrometry.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDifferentiation of isotopically labeled nucleotides using fast atom bombardment tandem mass spectrometryLarry M. Mallis, Frank M. Raushel, and David H. RussellCite this: Anal. Chem. 1987, 59, 7, 980–984Publication Date (Print):April 1, 1987Publication History Published online1 May 2002Published inissue 1 April 1987https://doi.org/10.1021/ac00134a012RIGHTS & PERMISSIONSArticle Views64Altmetric-Citations15LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (614 KB) Get e-Alerts Get e-Alerts

Amino acid sequence of Manduca sexta adipokinetic hormone elucidated by Combined Fast Atom Bombardment (FAB)/Tandem Mass Spectrometry

Combination of Fast Atom Bombardment Tandem Mass Spectrometry with Amino Acid Analysis assigns the amino acid sequence of the Manduca sexta adipokinetic hormone as pGlu-Leu-Thr-Phe-Thr-Ser-Ser-Trp-GlyNH 2. Similarities and differences with other invertebrate hormones and with mammalian glucagon are discussed.

Quantitative analysis of an N-oxide metabolite by fast atom bombardment tandem mass spectrometry.

An assay for the N-oxide metabolite of a benzazepine drug by fast atom bombardment ionization with tandem mass spectrometric analysis on a triple quadrupole mass spectrometer has been developed and validated for urine and plasma samples. This methodology allows analysis of this metabolite directly in crude sample extracts, without the need for extensive chromatography or sample derivatization. Quantification was accomplished with the use of a stable isotope analog of the analyte as an internal standard, using the selected reaction monitoring mode of operation.