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Tailored photocleavable peptides: fragmentation and neutralization pathways in high vacuum.

ABSTRACT: Photocleavable tags (PCTs) have the potential for excellent spatio-temporal control over the release of subunits of complex molecules. Here, we show that electrosprayed oligopeptides, functionalized by a tailored ortho-nitroarylether can undergo site-specific photo-activated cleavage under UV irradiation (266 nm) in high vacuum. The comparison of UV photodissociation (UVPD) and collision-induced dissociation (CID) points to the thermal nature of the cleavage mechanism, a picture corroborated by the temperature dependence of the process. Two competing photodissociation pathways can be identified. In one case a phenolate anion is separated from a neutral zwitterion. In the other case a neutral phenol derivative leaves a negatively charged peptide behind. To understand the factors favoring one channel over the other, we investigate the influence of the peptide length, the nature of the phenolic group and the position of the nitro-group (ortho vs. para). The observed gas phase cleavage of a para-nitro benzylic ether markedly differs from the established behavior in solution.

SUBMITTER: Debiossac M

PROVIDER: S-EPMC5932999 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Gas-phase structure and fragmentation pathways of singly protonated peptides with N-terminal arginine.

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Mapping Lipid Fragmentation for Tailored Mass Spectral Libraries.

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Matrix-assisted ionization vacuum for protein detection, fragmentation and PTM analysis on a high resolution linear ion trap-orbitrap platform.

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Unusual fragmentation of derivatized cysteine-containing peptides.

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| S-EPMC6430700 | biostudies-literature

Light-Induced Orthogonal Fragmentation of Crosslinked Peptides.

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| S-EPMC10466327 | biostudies-literature

Improved Detection and Fragmentation of Disulphide-Linked Peptides.

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