O-Acetylated Chemical Reporters of Glycosylation Can Display Metabolism-Dependent Background Labeling of Proteins but Are Generally Reliable Tools for the Identification of Glycoproteins.

ABSTRACT: Monosaccharide analogs bearing bioorthogonal functionalities, or metabolic chemical reporters (MCRs) of glycosylation, have been used for approximately two decades for the visualization and identification of different glycoproteins. More recently, proteomics analyses have shown that per-O-acetylated MCRs can directly and chemically react with cysteine residues in lysates and potentially cells, drawing into question the physiological relevance of the labeling. Here, we report robust metabolism-dependent labeling by Ac₄2AzMan but not the structurally similar Ac₄4AzGal. However, the levels of background chemical-labeling of cell lysates by both reporters are low and identical. We then characterized Ac₄2AzMan labeling and found that the vast majority of

SUBMITTER: Darabedian N 

PROVIDER: S-EPMC7198827 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature