Figure 4. Inhibition of GagProPol processing by the oxidant diamide is dependent on both cysteines of the embedded HIV-1 protease.

(A) In vitro transcription/translation with ³⁵S-methionine was carried out for 1 h in the absence (−) or presence (+) of 1 mM diamide. Samples were separated by LDS-PAGE and visualized by autoradiography. The precursors and products of GagProPol processing by the embedded protease are indicated. The pGPfs-1C plasmid construct used is indicated above the wells. (B) Densitometry was carried out on autoradiograms from 4 separate experiments under the conditions as described for Figure 4A and the extent of inhibition of processing calculated. The percent inhibition was calculated as (processing without diamide-processing with diamide)/(processing without diamide) x 100. Percent processing is calculated as in Figure 2. Values represent the average +/− the standard deviation from 4 independent experiments.