Dataset Information

Ultraviolet Photodissociation of tryptic peptide backbones at 213 nm

ABSTRACT: We analyzed the backbone fragmentation behavior of tryptic peptides of a four protein mixture and of E. coli lysate subjected to Ultraviolet Photodissociation (UVPD) at 213 nm on a commercially available UVPD-equipped tribrid mass spectrometer. We obtained 15,178 high-confidence peptide-spectrum matches by additionally recording a reference beam-type collision-induced dissociation (HCD) spectrum of each precursor. Type a, b and y ions were most prominent in UVPD spectra and median sequence coverage ranged from 5.8% (at 5 ms laser excitation time) to 45.0% (at 100 ms). Overall sequence fragment intensity remained relatively low (median: 0.4% (5 ms) to 16.8% (100 ms) of total intensity) and remaining precursor intensity high. Sequence coverage and sequence fragment intensity ratio correlated with precursor charge density, suggesting that UVPD at 213 nm may suffer from newly formed fragments sticking together due to non-covalent interactions. UVPD fragmentation efficiency therefore might benefit from supplemental activation, as was shown for ETD. Aromatic amino acids, most prominently tryptophan, facilitated UVPD. This points at aromatic tags as possible enhancers of UVPD. Data are available via ProteomeXchange and on spectrumviewer.org/db/UVPD_213nm_trypPep

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Equus Caballus (horse) Homo Sapiens (human) Escherichia Coli Gallus Gallus (chicken) Oryctolagus Cuniculus (rabbit)

SUBMITTER: Lars Kolbowski

LAB HEAD: Juri Rappsilber

PROVIDER: PXD018176 | Pride | 2020-05-07

REPOSITORIES: Pride

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Publications

Ultraviolet Photodissociation of Tryptic Peptide Backbones at 213 nm.

Kolbowski Lars L Belsom Adam A Rappsilber Juri J

Journal of the American Society for Mass Spectrometry 20200522 6

We analyzed the backbone fragmentation behavior of tryptic peptides of a four-protein mixture and of <i>E. coli</i> lysate subjected to ultraviolet photodissociation (UVPD) at 213 nm on a commercially available UVPD-equipped tribrid mass spectrometer. We obtained 15 178 unique high-confidence peptide UVPD spectrum matches by recording a reference beam-type collision-induced dissociation (HCD) spectrum of each precursor, ensuring that our investigation includes a broad selection of peptides, incl ...[more]

PMID: 32352297

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Project description:A causal role of mutations in genes encoding for multiple general transcription factors in neurodevelopmental disorders including autism suggested that alterations at the global level of gene expression regulation might also relate to disease risk in sporadic cases of autism. This premise can be tested by evaluating for global changes in the overall distribution of gene expression levels. For instance, in mice, we recently showed that variability in hippocampal-dependent behaviors was associated with variability in the pattern of the overall distribution of gene expression levels, as assessed by variance in the distribution of gene expression levels in the hippocampus. We hypothesized that a similar change in the variance in gene expression levels might be found in children with autism. 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Dataset Information

Ultraviolet Photodissociation of tryptic peptide backbones at 213 nm

Publications

Ultraviolet Photodissociation of Tryptic Peptide Backbones at 213 nm.

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