Viruses (5 microliters, dried overnight) were deglycosylated with 5 microliters metacresol and 20 microliters of trifluoromethanesulfonic acid for 2 hrs at 0C. Samples were neutralized with 3 volumes of N-ethylmorpholine and precipitated by adding 5 volumes of ethanol, 2 microliters of 1% Ficoll and incubation at -20C for 30 min.
Interestingly only CVM shows convincing deglycosylation of the large protein (vp130?). Vp130 corresponds to A140/145 which is a basic protein (vertex) containing PAPK repeats. Interestingly PBi viruses have two genes related to A140/145. CVM also exhibits a protein doublet and apparently corresponding cleavage products.) Wang et al (PNAS, 1993) show clear evidence for a glycosylated large protein (and cleavage product?) which are affected by glycosylation mutants in parallel with the major capsid protein.