TABLE 4.

Glycosylation between chymotryptic cleavage sites in Pr80^enva

^aThe locations of each partial chymotryptic cleavage site were calculated from the lengths of the FLAG-tagged fragment shown in Fig. 8A and B as well as examination of the Env sequence for predicted chymotryptic sites. This was possible because the FLAG tag was located at the C terminus of all detected fragments. Thus, Pr80^env could be divided into different regions delineated by the cleavage sites. The residues are numbered from the beginning of the Env reading frame; after cleavage of the signal peptide, the amino terminus of Pr80^env is located at residue 84. The amount of glycosylation between chymotryptic cleavage sites was estimated by subtracting the glycosylation levels (Table 3) of the smaller fragment from the immediately larger fragment, shown here in parentheses next to the residue ranges. All values are rounded to the nearest whole number and are shown in kilodaltons (see Fig. 8C for a graphical representation of the results).