Purification of porcine proinsulin by high-performance liquid chromatography.
A procedure has been developed for purification of porcine proinsulin by high-performance liquid chromatography from a preparation obtained as a side product during the Sephadex G-50 gel filtration of an impure porcine insulin preparation. Reversed-phase chromatography was carried out on octadecylsilica as the stationary phase with graded mixtures of acetonitrile or methanol-acetonitrile and phosphate buffer pH 2.4 as the mobile phase. The crude preparation separated into five different groups of proteins, the proinsulin-containing peak being identified by the co-eluting internal proinsulin marker. After purification by conventional procedures (separation, pooling, freeze drying, desalting, reprecipitation and drying) this peak fraction was rechromatographed by high-performance liquid chromatography (for final purification) to give a single peak protein which had identical electrophoretic mobility to that of commercial porcine proinsulin, and which converted to a protein with electrophoretic mobility similar to that of porcine insulin.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D007328:Insulin / Q000032:analysis*; D011384:Proinsulin / Q000302:isolation & purification*; D013552:Swine
D007328:Insulin; D011384:Proinsulin