FIG. 2.

Assays of HIV PR and B3 proteolytic activities in E. coli. (A and B) DHT1 cells were cotransformed with plasmids expressing ACp5 and N7-PR-C7 (section 1), ACp5 and N22-PR-C29 (section 2), ACp5 and N7-B3-C7 (section 3), or ACp5 and N22-B3-C29 (section 4) or with empty vector (pUC19) and plasmids expressing ACp5 (section 5) or T25 (section 6). Cotransformants were plated on MacConkey-maltose plus kanamycin and ampicillin (A) or on the same medium supplemented with 100 μM saquinavir (B) and grown for 48 h at 30°C. (C) Recombinant ACp5 (apparent molecular mass of 45 kDa), in DHT1 cells expressing the indicated proteins, was detected by Western blot analysis as described in Materials and Methods. β-Galactosidase activities and cAMP levels in the corresponding samples were measured as described in Materials and Methods.