Modulating the selectivity of affinity absorbents to multi-phosphopeptides by a novel competitive substitution strategy

ABSTRACT: Although many affinity adsorbents have been developed for phosphopeptides enrichment, high-specifically capturing the multi-phosphopeptides is still a big challenge. Here, we investigated the mechanism of phosphate ions coordination and substitution on affinity adsorbents surfaces and modulated the selectivity of affinity adsorbents to multi-phosphopeptides based on the different capability of mono- and multi-phosphopeptides in competitively substituting the pre-coordinated phosphate ions at strong acidic condition. We demonstrated both the species of pre-coordinated phosphate ions and the substituting conditions played crucial roles in modulating the enrichment selectivity to multi-phosphopeptides, and the pre-coordinated affinity materials with relative more surfaces positive charges exhibited better enrichment efficiency due to the cooperative effect of electrostatic interaction and competitive substitution. Finally, an enrichment selectivity of 85% to multi-phosphopeptides was feasibly achieved with 66% improvement in identification numbers for complex protein sample extracted from HepG2 cells.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Hepatocyte, Cell Culture

SUBMITTER: Zheyi Liu  

LAB HEAD: Fangjun Wang

PROVIDER: PXD004252 | Pride | 2016-08-03

REPOSITORIES: Pride