A rapid separation of S100 subunits by high performance liquid chromatography: the subunit compositions of S100 proteins.

The subunits of S100 protein were dissociated and separated from each other by high performance liquid chromatography on a macroreticular poly-styrene resin, using an acetonitrile-trifluoroacetic acid solvent system. The separation was completed within 80 min in monitoring the effluent at 210 and 280 nm, allowing a rapid and sensitive identification of each S100 protein in terms of subunit composition, and a simultaneous purification of subunits. The method enabled to estimate the subunit compositions of S100a, S100b, and S100a0 protein purified from bovine brain, and revealed a micro-heterogeneity of S100 subunits as applied to the mixtures of S100 protein prepared from bovine, human and rat brain.