Selective enrichment of Ser‐/Thr‐phosphorylated peptides in the presence of Ser‐/Thr‐glycosylated peptides

Modification through β-elimination has proven to be a reliable first step in the approach for enrichment of serine/threonine-phopshorylated (Ser-/Thr) peptides. However, under harsh basic conditions, Ser-/Thr-glycosylated peptides are susceptible to β-elimination as well. Therefore, we have optimized these conditions to achieve a β-elimination that is highly selective for phosphorylated peptides. This is the first report of selective β-elimination and enrichment of phosphorylated peptides in the presence of glycosylated peptides.