title: Comparison of the human immunodeficiency virus type 1 and 2 proteases by hybrid gene construction and trans-complementation.
abstract: To determine the cleavage specificity of the proteases of the type 1 and 2 human immunodeficiency viruses (HIV-1, HIV-2), we interchanged this domain of the polymerase (pol) genes and analyzed the maturation programs of the chimeric polyproteins in an Escherichia coli expression system. In both cases, release of reverse transcriptase and integrase was observed, together with the respective 10-kDa protease form resulting from autocatalysis, although the maturation proceeded less efficiently compared to the homologous system. In further experiments, the ability of both HIV-1 and HIV-2 proteases to release in vivo gag p24 from an in-frame fusion of the full length gag and protease precursors was analyzed. In either case, p24 was released, albeit with greater efficiency in the heterologous gene construction. In vitro mixed lysate experiments with the HIV-1 gag precursor furthermore demonstrate that both enzymes respond to the aspartyl proteinase inhibitor pepstatin A. Taken together, these results illustrate that although different cleavage recognition sequences exist for HIV-1 and -2, they are amenable to the proteases of both viruses, but additionally that subtle differences in the mode of action of both enzymes are observable.
authors.affiliation: Central Research Units, F. Hoffmann-La Roche & Co., Ltd., Basel, Switzerland.
authors.forename: S F
authors.initials: SF
authors.lastname: Le Grice
authors.forename: R
authors.initials: R
authors.lastname: Ette
authors.forename: J
authors.initials: J
authors.lastname: Mills
authors.forename: J
authors.initials: J
authors.lastname: Mous
mesh_terms: D002384:Catalysis; D003001:Cloning, Molecular; D010450:Endopeptidases / Q000235:genetics* / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics; D005813:Genes, Synthetic; D005816:Genetic Complementation Test; D016333:HIV Protease; D015497:HIV-1 / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D015498:HIV-2 / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D010436:Pepstatins / Q000494:pharmacology; D011480:Protease Inhibitors; D011993:Recombinant Fusion Proteins / Q000502:physiology; D012191:Retroviridae Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000502:physiology
chemical_list: D010436:Pepstatins; D011480:Protease Inhibitors; D011993:Recombinant Fusion Proteins; D012191:Retroviridae Proteins; C014195:Streptomyces pepsin inhibitor; D010450:Endopeptidases; D016333:HIV Protease; C031375:pepstatin