A structural polypeptide of the baculovirus Autographa californica nuclear polyhedrosis virus contains O-linked N-acetylglucosamine.
A structural glycopeptide, gp41, derived from the occluded virus of the baculovirus Autographa californica nuclear polyhedrosis virus was characterized. The peptide specifically bound wheat germ agglutinin but was not recognized by a panel of seven other lectins. Reactivity with wheat germ agglutinin was eliminated by treatment of gp41 with beta-N-acetylglucosaminidase, indicating that N-acetylglucosamine (GlcNAc) was present as terminal residues. gp41 was efficiently galactosylated by galactosyltransferase only in the presence of Nonidet P-40, suggesting that GlcNAc residues are not exposed on the surface of the virion. Metabolic labelling of gp41 with [3H]GlcNAc occurred in the presence of tunicamycin. The carbohydrate was released by alkaline borohydride treatment and comigrated with N-acetylglucosaminitol in descending paper chromatography. The data indicate that gp41 contains single residues of GlcNAc O glycosidically linked to the polypeptide chain. Evidence suggesting that gp41 is located in the region between the envelope membrane and the capsid (defined here as the tegument) of the occluded virus is also presented.