FIG. 3.

Inhibition of DNA-dependent DNA polymerase RT activity by NNRTIs determined by gel-based RT assay. (A) Graphic representation of the primer-template system (ppt18-ppt57) used to monitor the inhibition of HIV-1 RT DNA polymerase activity by NNRTIs. +1 and +4, the positions of the first and the last nucleotide incorporated, respectively. (B) Dose-dependent inhibition of DNA polymerase activity by NNRTIs. Reactions were performed with increasing concentrations of the NNRTIs. The positions of the labeled primer (P) and the full-length extension product (+4) are indicated on the left. The concentrations of the NNRTIs used are as follows: for ETR, 0, 17, 26, 39, 58.5, 87.8, 131, 197.5, 296, 444, and 666 nM and 1 and 10 μM; for DAP 0, 23, 34, 52, 78, 117, 175, 260, 395, 590, 888, 1,330, and 2,000 nM; for EFV, 0, 4, 8, 16, 32, 64, 128, 180, 250, 352, and 493 nM and 10 and 100 μM; and for NVP, 0, 10, 31, 95, 285, and 857 nM; 2.5, 7.7, 23, 69, 208, and 625 μM; and 1.87 mM.