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In-Source Decay and Pseudo-MS3 of Peptide and Protein Ions Using Liquid AP-MALDI.

ABSTRACT: Atmospheric pressure MALDI on a Q-Exactive instrument was optimized for in-source decay and pseudo-MS3. The dependence of AP-MALDI ISD on the MALDI liquid matrix was investigated for peptides and proteins. The liquid matrices enabled long-life ISD signal, and exhibited high fragment ion yield and signal stability. Extensive a-, b-, c-, y-, and z-type fragment series were observed depending on the matrix used but were most extensive with 2,5-DHB. Complete sequence coverage of small peptide and intact protein-terminus sequence tags were obtained and confirmed using HCD as a pseudo-MS3 method. Graphical Abstract ?.

SUBMITTER: Ait-Belkacem R

PROVIDER: S-EPMC5088222 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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In-Source Decay and Pseudo-MS<sup>3</sup> of Peptide and Protein Ions Using Liquid AP-MALDI.

Ait-Belkacem Rima R Dilillo Marialaura M Pellegrini Davide D Yadav Avinash A de Graaf Erik L EL McDonnell Liam A LA

Journal of the American Society for Mass Spectrometry 20161017 12

Atmospheric pressure MALDI on a Q-Exactive instrument was optimized for in-source decay and pseudo-MS<sup>3</sup>. The dependence of AP-MALDI ISD on the MALDI liquid matrix was investigated for peptides and proteins. The liquid matrices enabled long-life ISD signal, and exhibited high fragment ion yield and signal stability. Extensive a-, b-, c-, y-, and z-type fragment series were observed depending on the matrix used but were most extensive with 2,5-DHB. Complete sequence coverage of small pep ...[more]

PMID: 27752913

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