Changes in Protein-bound Oligomannosyl Type Glycans During Semliki Forest Virus Maturation

Labelled oligomannosyl type glycans of E2 protein of Semliki Forest virus were liberated by treatment with endo--N-acetylglucosaminidase H, as well as by hydrazinolysis and analysed by paper chromatography. The protein-bound virus oligosaccharides were a mixture of Man₇GlcNAc₂, Man₆GlcNAc₂ and Man₅GlcNAc₂, and Man₈GlcNAc₂ also appeared to be present. P62 protein, the direct precursor of E2, was labelled by supplying infected BHK cells with 2-³H-mannose for 5 min. The oligomannosyl glycans of the P62 proteins formed were about two monosaccharide units larger than those of the mature virus E2 proteins.