193-nm photodissociation of singly and multiply charged peptide anions for acidic proteome characterization.

Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, TX 78712, USA.
Proteomics (Impact Factor: 4.43). 02/2011; 11(7):1329-34. DOI: 10.1002/pmic.201000565
Source: PubMed

ABSTRACT 193-nm ultraviolet photodissociation (UVPD) was implemented to sequence singly and multiply charged peptide anions. Upon dissociation by this method, a-/x-type, followed by d and w side-chain loss ions, were the most prolific and abundant sequence ions, often yielding 100% sequence coverage. The dissociation behavior of singly and multiply charged anions was significantly different with higher charged precursors yielding more sequence ions; however, all charge states investigated (1- through 3-) produced rich diagnostic information. UVPD at 193  nm was also shown to successfully differentiate and pinpoint labile phosphorylation modifications. The sequence ions were produced with high abundances, requiring limited averaging for satisfactory spectral quality. The intact, charge-reduced radical products generated by UV photoexcitation were also subjected to collision-induced dissociation (termed, activated-electron photodetachment dissociation (a-EPD)), but UVPD alone yielded more predictable and higher abundance sequence ions. With the use of a basic (pH∼11.5), piperidine-modified mobile phase, LC-MS/UVPD was implemented and resulted in the successful analysis of mitogen-activated pathway kinases (MAPKs) using ultrafast activation times (5  ns).

  • [Show abstract] [Hide abstract]
    ABSTRACT: Photodissociation mass spectrometry combines the ability to activate and fragment ions using photons with the sensitive detection of the resulting product ions by mass spectrometry. This combination affords a versatile tool for characterization of biological molecules. The scope and breadth of photodissociation mass spectrometry have increased substantially over the past decade as new research groups have entered the field and developed a number of innovative applications that illustrate the ability of photodissociation to produce rich fragmentation patterns, to cleave bonds selectively, and to target specific molecules based on incorporation of chromophores. This review focuses on many of the key developments in photodissociation mass spectrometry over the past decade with a particular emphasis on its applications to biological molecules.
    Chemical Society Reviews 01/2014; · 24.89 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: RATIONALE: We implemented, for the first time, laser-induced dissociation (LID) within a modified hybrid linear ion trap mass spectrometer, QTrap, while preserving the original scanning capabilities and routine performance of the instrument. METHODS: Precursor ions of interest were mass-selected in the first quadrupole (Q1), trapped in the radiofrequency-only quadrupole (q2), photodissociated under irradiation with a 193- or 266-nm laser beam in the third quadrupole (q3), and mass-analyzed using the linear ion trap. RESULTS: LID of singly charged protonated peptides revealed, in addition to conventional amide-bond cleavages, preferential fragmentation at Cα -C/N-Cα bonds of the backbone as well as at the Cα -Cβ /Cβ -Cγ bonds of the side-chains. The LID spectra of [M+H](+) featured product ions that were very similar to the observed radical-induced fragmentations in the CID spectra of analogous odd-electron radical cations generated through dissociative electron-transfer in metal-ligand-peptide complexes or through laser photolysis of iodopeptides. CONCLUSIONS: LID of [M+H](+) ions results in fragmentation channels that are comparable with those observed upon the CID of M(•+) ions, with a range of fascinating radical-induced fragmentations. Copyright © 2013 John Wiley & Sons, Ltd.
    Rapid Communications in Mass Spectrometry 05/2013; 27(10):1119-1127. · 2.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mass spectrometry (MS)-based studies of synthetic polymers often characterise detected polymer components using mass data alone. However when mass-based characterisations are ambiguous, tandem MS (MS/MS) offers a means by which additional analytical information may be collected. This review provides a synopsis of two particularly promising methods of dissociating polymer ions during MS/MS: electron-capture and electron-transfer dissociation (ECD and ETD, respectively). The article opens with a summary of the basic characteristics and operating principles of ECD and ETD, and relates these techniques to other methods of dissociating gas-phase ions, such as collision-induced dissociation (CID). Insights into ECD- and ETD-based MS/MS, gained from studies into proteins and peptides, are then discussed in relation to polymer chemistry. Finally, ECD- and ETD-based studies into various classes of polymer are summarised; for each polymer class, ECD- and ETD-derived data are compared to CID-derived data. These discussions identify ECD and ETD as powerful means by which unique and diagnostically useful polymer ion fragmentation data may be generated, and techniques worthy of increased utilisation by the polymer chemistry community.
    Analytica chimica acta 01/2014; 808:44-55. · 4.31 Impact Factor

Full-text (2 Sources)

Available from
Jun 11, 2014