title: Disruption of the HIV-1 protease dimer with interface peptides: structural studies using NMR spectroscopy combined with [2-(13)C]-Trp selective labeling.
abstract: HIV-1 protease (HIV-1 PR), which is encoded by retroviruses, is required for the processing of gag and pol polyprotein precursors, hence it is essential for the production of infectious viral particles. In vitro inhibition of the enzyme results in the production of progeny virions that are immature and noninfectious, suggesting its potential as a therapeutic target for AIDS. Although a number of potent protease inhibitor drugs are now available, the onset of resistance to these agents due to mutations in HIV-1 PR has created an urgent need for new means of HIV-1 PR inhibition. Whereas enzymes are usually inactivated by blocking of the active site, the structure of dimeric HIV-1 PR allows an alternative inhibitory mechanism. Since the active site is formed by two half-enzymes, which are connected by a four-stranded antiparallel beta-sheet involving the N- and C- termini of both monomers, enzyme activity can be abolished by reagents targeting the dimer interface in a region relatively free of mutations would interfere with formation or stability of the functional HIV-1 PR dimer. This strategy has been explored by several groups who targeted the four-stranded antiparallel beta-sheet that contributes close to 75% of the dimerization energy. Interface peptides corresponding to native monomer N- or C-termini of several of their mimetics demonstrated, mainly on the basis of kinetic analyses, to act as dimerization inhibitors. However, to the best of our knowledge, neither X-ray crystallography nor NMR structural studies of the enzyme-inhibitor complex have been performed to date. In this article we report a structural study of the dimerization inhibition of HIV-1 PR by NMR using selective Trp side chain labeling.
authors.affiliation: Institut de Recerca Biomèdica, Parc Científic de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Frutos
authors.forename: Ricard A
authors.initials: RA
authors.lastname: Rodriguez-Mias
authors.forename: Sergio
authors.initials: S
authors.lastname: Madurga
authors.forename: Bruno
authors.initials: B
authors.lastname: Collinet
authors.forename: Michèle
authors.initials: M
authors.lastname: Reboud-Ravaux
authors.forename: Dolors
authors.initials: D
authors.lastname: Ludevid
authors.forename: Ernest
authors.initials: E
authors.lastname: Giralt
mesh_terms: D002247:Carbon Isotopes; D019281:Dimerization; D016333:HIV Protease / Q000737:chemistry* / Q000235:genetics; D017320:HIV Protease Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D019906:Nuclear Magnetic Resonance, Biomolecular; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D020836:Protein Structure, Quaternary / Q000187:drug effects; D014364:Tryptophan / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D017320:HIV Protease Inhibitors; D009842:Oligopeptides; D014364:Tryptophan; D016333:HIV Protease