A chemoenzymatic approach toward the rapid and sensitive detection of O-GlcNAc posttranslational modifications

J Am Chem Soc. 2003 Dec 31;125(52):16162-3. doi: 10.1021/ja038545r.


We report a new chemoenzymatic strategy for the rapid and sensitive detection of O-GlcNAc posttranslational modifications. The approach exploits the ability of an engineered mutant of beta-1,4-galactosyltransferase to selectively transfer an unnatural ketone functionality onto O-GlcNAc glycosylated proteins. Once transferred, the ketone moiety serves as a versatile handle for the attachment of biotin, thereby enabling chemiluminescent detection of the modified protein. Importantly, this approach permits the rapid visualization of proteins that are at the limits of detection using traditional methods. Moreover, it bypasses the need for radioactive precursors and captures the glycosylated species without perturbing metabolic pathways. We anticipate that this general chemoenzymatic strategy will have broad application to the study of posttranslational modifications.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acetylglucosamine / analysis
  • Acetylglucosamine / metabolism*
  • Animals
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism
  • Biotin
  • Cyclic AMP Response Element-Binding Protein / analysis
  • Cyclic AMP Response Element-Binding Protein / metabolism
  • Glycoproteins / analysis
  • Glycoproteins / metabolism*
  • Glycosylation
  • Horseradish Peroxidase / chemistry
  • Horseradish Peroxidase / metabolism
  • Luminescent Measurements
  • N-Acetyllactosamine Synthase / chemistry
  • N-Acetyllactosamine Synthase / metabolism*
  • alpha-Crystallins / analysis
  • alpha-Crystallins / metabolism


  • Bacterial Proteins
  • Cyclic AMP Response Element-Binding Protein
  • Glycoproteins
  • Strep-avidin conjugated horseradish peroxidase
  • alpha-Crystallins
  • Biotin
  • Horseradish Peroxidase
  • N-Acetyllactosamine Synthase
  • Acetylglucosamine