RESUMO
Site-specific proteolysis is an important regulatory mechanism in many basic cellular processes as well as playing critical roles in the life cycle of viruses and other pathogenic organisms. For the human immunodeficiency virus (HIV) the encoded protease is required for the replication of the virus and has been the target of novel antiviral therapeutics. However, the emergence of inhibitor-resistant viral strains has become an increasingly significant clinical problem. Using a bacteriophage-based genetic selection, a bank of inhibitor-resistant mutants in this protease has been isolated that includes mutations that correlate with resistant clinical isolates. The rapid selection of such mutations has implications for the prediction of relevant mutations and may be applicable to other viral systems.