Dataset Information

Retention Order Reversal of Phosphorylated and Unphosphorylated Peptides in Reversed-Phase LC/MS

ABSTRACT: Protein phosphorylation is one of the most ubiquitous post-translational modifications in human, and trypsin-digested phosphorylated peptides have been analyzed by reversed phase LC/MS using C18-silica columns under the acidic conditions to profile human phosphoproteomes. Here, we reported that phosphopeptides generally retain stronger than their unphosphorylated counterparts when C18-silica columns are used with acetic acid or formic acid as an ion-pairing reagent, whereas the retention order is reversed when less hydrophobic stationary phases such as C4-silica columns are used or more acidic and hydrophobic ion-pairing reagents such as trifluoroacetic acid are used with C18-silica columns. These phenomena could be explained by smaller S-values of phosphopeptides in linear solvation strength theory, based on the reduced net charge caused by intramolecular interaction between phosphate and basic groups.

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Yasushi Ishihama

PROVIDER: PXD010327 | JPOST Repository | Sun Nov 11 00:00:00 GMT 2018

REPOSITORIES: jPOST

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Dataset's files

Source:

			Action	DRS
	180314ko02NPS_phos_Fr1.wiff	Wiff
	180314ko02NPS_phos_Fr1.wiff.scan	Wiff
	180314ko03NPS_phos_Fr2.wiff	Wiff
	180314ko03NPS_phos_Fr2.wiff.scan	Wiff
	180314ko04NPS_phos_Fr3.wiff	Wiff

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Publications

Retention Order Reversal of Phosphorylated and Unphosphorylated Peptides in Reversed-Phase LC/MS.

Ogata Kosuke K Krokhin Oleg V OV Ishihama Yasushi Y

Analytical sciences : the international journal of the Japan Society for Analytical Chemistry 20180727 9

Protein phosphorylation is one of the most ubiquitous post-translational modifications in humans, and trypsin-digested phosphorylated peptides have been analyzed by reversed phase LC/MS using C18-silica columns under acidic conditions to profile human phosphoproteomes. Here, we report that phosphopeptides generally exhibit stronger retention than their unphosphorylated counterparts when C18-silica columns are used with acetic acid or formic acid as an ion-pairing reagent, whereas the retention o ...[more]

PMID: 30058604

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