FIG. 1.

Cathepsin digestion of MN-rgp120. MN-rgp120 was digested with either cathepsin L (A), cathepsin S (B), or cathepsin D (C). At the indicated times, samples were removed, the digestion was stopped by the addition of liquid nitrogen, and samples were prepared for SDS-PAGE analysis. Bands were visualized by Coomassie blue staining. The mobilities of the fragments identified are shown to the left of each panel. The mobility values of prestained molecular mass markers are shown to the right of panel C.