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Updated: Jul 31, 2026

Glycopeptide Capture for Cell Surface Proteomics
Published on: May 9, 2014
Covalent peptide transfer to cell membrane proteins (peptidyl transferase)
1Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA.
Abstract:
HL60 cells, rabbit peritoneal granulocytes or membrane preparations of these cells incorporate radioactivity when reacted with the radioactive peptide tuftsin [3H Pro3]-Thr-Lys-Pro-Arg. The radioactivity which is not diminished by repeated treatments with TCA and NaOH, is covalently bound to a membrane acceptor protein of 100 kDa. The peptide is not displaced by large concentrations of its constituent amino acids. The acceptor protein is resolved into one labeled peak by gel filtration on Sephadex G-200, Sephacryl S-300 and by SDS-PAGE. Digestion by trypsin and chymotrypsin results in the production of smaller fragments.
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