title: The PO protein of chick sciatic nerve myelin: purification and partial characterization.
abstract: The PO protein of the myelin of chick sciatic nerve was isolated and purified by propanoic acid extraction of peripheral nervous system (PNS) myelin, delipidation, Sepharose CL-6B chromatography in the presence of sodium dodecyl sulfate (SDS), and preparative SDS-polyacrylamide gel electrophoresis (PAGE). Approximately 15% of the PO protein in the sciatic nerve myelin was recovered in a homogeneous state. The purified protein monomer has an apparent molecular weight of 32.1K as determined by gel electrophoresis. The PO protein undergoes extensive aggregation during exhaustive dialysis and freeze-drying and yields stable dimers, trimers, and tetramers. The aggregation of the PO protein after freeze-drying is independent of the presence of a reducing agent (2-mercaptoethanol) in the solubilizing medium. The PO protein is a glycoprotein. The amino acid composition of the chick PO protein indicates a definite species difference when compared with mammalian PO proteins although the NH2-terminal isoleucine residue seems to have been retained during evolution.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D002645:Chickens; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008970:Molecular Weight; D018993:Myelin P0 Protein; D009185:Myelin Proteins / Q000302:isolation & purification*; D009186:Myelin Sheath / Q000032:analysis*; D011817:Rabbits; D012584:Sciatic Nerve / Q000032:analysis*; D012794:Sialic Acids / Q000032:analysis; D013045:Species Specificity
chemical_list: D000596:Amino Acids; D018993:Myelin P0 Protein; D009185:Myelin Proteins; D012794:Sialic Acids