Table 1.

Summary of O-GlcNAc enrichment methods

Enrichment	Binding affinity	Specificity	Enriches all O-GlcNAc	Comments	References
WGA Lectin	Weak	Enriches most glycopeptides	Yes	Probably the highest sensitivity of the methods owing to not requiring a labeling step before enrichment	(14, 15, 39, 40, 42, 45)
BEMAD	Medium	Enriches most O-linked modifications	Yes	As original modification is replaced, it is important to have independent verification that it was O-GlcNAc	(32, 33)
Enzymatic Tagging	Strong	Enriches terminal GlcNAc-containing glycopeptides	Yes		(17, 19, 20, 22, 41)
Metabolic Tagging	Strong	Enriches all types of GlcNAc-containing glycopeptides	Subset of newly modified	Lower sensitivity owing to competing UDP-GlcNAc levels leading to substoichiometric incorporation	(25, 28, 56)
Immunoprecipitation	Weak	Enriches subset of O-GlcNAc	Each enriches a subset	Will only enrich some modified peptides	(10, 11, 30)