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Compendium of chromatographic behavior of post-translationally and chemically modified peptides in bottom-up proteomic experiments

ABSTRACT: We have systematically evaluated the chromatographic behavior of post-translationally / chemically modified peptides using data spanning over 60 of the most relevant modifications. These retention properties were measured for standard bottom-up proteomic settings (fully porous C18 separation media, 0.1% formic acid as ion pairing modifier) using collections of modified/non-modified peptide pairs. Working in units of hydrophobicity index (HI, %ACN) and evaluating the average retention shifts (DHI) represents the simplest approach to describe the effect of modifications from a didactic point of view. Plotting HI values for modified (y-axis) vs. unmodified (x-axis) counterparts generates unique slope and intercept values for each modification defined by the chemistry of the modifying moiety: its hydrophobicity, size, pKa of ionizable groups and position of the altered residue. These composition-dependent correlations can be used for coarse incorporation of PTMs into models for prediction peptide retention.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Escherichia Coli (ncbitaxon:562) Danio Rerio (ncbitaxon:7955) Homo Sapiens (ncbitaxon:9606)

SUBMITTER: Oleg Krokhin

PROVIDER: MSV000092093 | MassIVE | Sat Jun 03 05:03:00 BST 2023

REPOSITORIES: MassIVE

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