Utilization of a new biotinylation reagent in the development of a nondiscriminatory investigative approach for the study of cell surface proteins.

In order to circumvent the various problems encountered during the study of membrane-bound proteins, we designed and synthesized a novel membrane-impermeable biotinylation reagent incorporating chemical properties compatible with this goal. We then developed a nondiscriminatory analytical procedure for such studies which overcomes possible selectivity, contamination and solubility problems. The necessary steps (labeling, limited in situ proteolysis, affinity purification) are all conducted in mild or near native conditions. This versatile method could provide an accurate picture of the cell surface proteome.