Specific Affinity Enrichment of Electrochemically Cleaved Peptides Based on Cu(II)-Mediated Spirolactone Tagging.

ABSTRACT: Specific digestion of proteins is an essential step for mass spectrometry-based proteomics, and the chemical labeling of the resulting peptides is often used for peptide enrichment or the introduction of desirable tags. Electrochemical oxidation yielding specific cleavage C-terminal to tyrosine (Tyr) and tryptophan (Trp) residues provides a potential alternative to enzymatic digestion and a possibility for further chemical labeling by introducing reactive spirolactone moieties. However, spirolactone-containing peptides suffer from low stability due to hydrolysis and intramolecular side reactions. We found that Cu(II) ions stabilize the spirolactone and prevent intramolecular side reactions during chemical labeling, allowing efficient chemical tagging with a reduced excess of labeling reage

SUBMITTER: Zhang T 

PROVIDER: S-EPMC5510089 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature