Dataset Information

Fractionation of phosphopeptides using reversed phase microcolumn prior to LC-MS analysis

ABSTRACT: A protocol for an improved phosphopeptide identification in tryptically digested complex peptide samples is described. The common TiO2 based phoshopeptide enrichment is coupled to a simple peptide fractionation protocol with following LC-MS analysis of the obtained fractions and proteomic identification of phosphorylated peptides. The fractions are obtained by an optimized protocol for peptide fractionation using a home-made capillary column coupled to a microgradient elution using a gastight microsyringe. The protocol leads to a substantially increased number of phosphopeptides (more than twice).

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: Pavel Rehulka

LAB HEAD: Jiri Stulik

PROVIDER: PXD018663 | Pride | 2020-08-31

REPOSITORIES: pride

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			Action	DRS
	12042019_257_PR_MO-TiO2frac-sk1fr1.raw	Raw
	12042019_258_PR_MO-TiO2frac-sk1fr2.raw	Raw
	12042019_259_PR_MO-TiO2frac-sk1fr3.raw	Raw
	12042019_261_PR_MO-TiO2frac-sk1fr4.raw	Raw
	12042019_262_PR_MO-TiO2frac-sk1fr5.raw	Raw

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Publications

Fractionation of Enriched Phosphopeptides Using pH/Acetonitrile-Gradient-Reversed-Phase Microcolumn Separation in Combination with LC-MS/MS Analysis.

Ondrej Martin M Rehulka Pavel P Rehulkova Helena H Kupcik Rudolf R Tichy Ales A

International journal of molecular sciences 20200601 11

Mass spectrometry (MS) is a powerful and sensitive method often used for the identification of phosphoproteins. However, in phosphoproteomics, there is an identified need to compensate for the low abundance, insufficient ionization, and suppression effects of non-phosphorylated peptides. These may hamper the subsequent liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis, resulting in incomplete phosphoproteome characterization, even when using high-resolution instrument ...[more]

PMID: 32492839

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