POTATO-VIRUS-X COAT PROTEIN - A GLYCOPROTEIN

The coat protein (CP) genes of all the strains of potato virus X (PVX) code for a protein of 25 kDa. Analysis of the CP by SDS-PAGE shows a migration mobility of 27 to 29 kDa, depending of the strain. Amino aci d identity between some strains is too high to explain such abnormal m igration by differences in primary structure of the protein. Periodate oxidation demonstrated the presence of carbohydrate moieties in purif ied CP of six PVX strains (cp, CP4, HB, MS, DX, CS35), and trifluorome thanesulfonic acid treatment identified glycosylated and nonglycosylat ed bands in SDS-PAGE complex patterns of CP and in Western blots. Dige stion with glycosidases, recognition by lectins, and mild alkali treat ment (beta-elimination) of PVX CP indicated the presence of an O-linke d sugar. (C) 1994 Academic Press, Inc.,