Enhancing Top-Down Analysis Using Chromophore-Assisted Infrared Multiphoton Dissociation from (Phospho)peptides to Protein Assemblies.

ABSTRACT: Infrared multiphoton dissociation (IRMPD) has been used in mass spectrometry to fragment peptides and proteins, providing fragments mostly similar to collisional activation. Using the 10.6 μm wavelength of a CO₂ laser, IRMPD suffers from the relative low absorption cross-section of peptides and small proteins. Focusing on top-down analysis, we investigate different means to tackle this issue. We first reassess efficient sorting of phosphopeptides from nonphosphopeptides based on IR-absorption cross-sectional enhancement by phosphate moieties. We subsequently demonstrate that a myo-inositol hexakisphosphate (IP6) noncovalent adduct can substantially enhance IRMPD for nonphosphopeptides and that this strategy can be extended to proteins. As a natural next step, we show that native

SUBMITTER: Greisch JF 

PROVIDER: S-EPMC7711774 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature