Characterization of the transmembrane serine receptor by capillary zone electrophoresis

Abstract

SummaryCapillary zone electrophoresis (CZE) was applied to the characterization of the transmembrane serine receptor in biosynthetic samples. The serine receptor, otherwise known as Tsr (taxis to serine and repellents), is a 60,000 Dalton intrinsic membrane protein whose periplasmic domain (ligand binding domain) reversibly binds the amino acid serine. In general, the electrophoresis of intrinsic membrane proteins is difficult due to severe solubility problems and adsorption which occurs during the electrophoretic run. This is due to the tendency of these types of proteins to undergo aggregation, self-aggregation and precipitation in aqueous environments. The addition of percentage levels of the surfactant, sodium dodecyl sulfate (SDS), to a tetraborate run buffer was shown to be effective both in enhancing the solubility of intact Tsr and in preventing the adsorption of intact Tsr to the fused-silica capillary wall during electrophoretic analysis. Critical separation parameters such as run buffer concentration, surfactant concentration and surfactant type were optimized to give the best separation profiles.

Capillary Zone Electrophoresis-Tandem Mass Spectrometry for Top-Down Proteomics of Mouse Brain Integral Membrane Proteins

“…CZE-MS/MS for TDP analysis of single human cells has also been reported . CZE for membrane protein analysis started in the 1990s using background electrolytes containing a high concentration of salts or detergents. , CZE-MS methods have also been developed for BUP of hydrophobic peptides. , However, to the best of our knowledge, there is no report on coupling CZE to MS/MS online for TDP of IMPs.…”