During the last few decades, the treatment of HIV-infected patients by highly active antiretroviral therapy, including protease inhibitors (PIs), has become standard. Here, we present results of analysis of a patient-derived, multiresistant HIV-1 CRF02_AG recombinant strain with a highly mutated protease (PR) coding sequence, where up to 19 coding mutations have accumulated in the PR. The results of biochemical analysis in vitro showed that the patient-derived PR is highly resistant to most of the currently used PIs and that it also exhibits very poor catalytic activity. Determination of the crystal structure revealed prominent changes in the flap elbow region and S1/S1' active site subsites. While viral loads in the patient were found to be high, the insertion of the patient-derived PR into a HIV-1 subtype B backbone resulted in reduction of infectivity by 3 orders of magnitude. Fitness compensation was not achieved by elevated polymerase (Pol) expression, but the introduction of patient-derived gag and pol sequences in a CRF02_AG backbone rescued viral infectivity to near wild-type (wt) levels. The mutations that accumulated in the vicinity of the processing sites spanning the p2/NC, NC/p1, and p6pol/PR proteins lead to much more efficient hydrolysis of corresponding peptides by patient-derived PR in comparison to the wt enzyme. This indicates a very efficient coevolution of enzyme and substrate maintaining high viral loads in vivo under constant drug pressure.
- MeSH
- buněčné linie MeSH
- genové produkty gag - virus lidské imunodeficience genetika MeSH
- genové produkty pol - virus lidské imunodeficience genetika MeSH
- geny gag MeSH
- geny pol MeSH
- HEK293 buňky MeSH
- HIV infekce farmakoterapie virologie MeSH
- HIV-1 genetika izolace a purifikace fyziologie MeSH
- HIV-proteasa chemie genetika metabolismus MeSH
- inhibitory HIV-proteasy terapeutické užití MeSH
- krystalografie rentgenová MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- mutace MeSH
- peptidové fragmenty genetika MeSH
- virová léková rezistence genetika MeSH
- virová nálož MeSH
- vysoce aktivní antiretrovirová terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Názvy látek
- gag protein p1, Human immunodeficiency virus MeSH Prohlížeč
- genové produkty gag - virus lidské imunodeficience MeSH
- genové produkty pol - virus lidské imunodeficience MeSH
- HIV-proteasa MeSH
- inhibitory HIV-proteasy MeSH
- p2 gag peptide, Human immunodeficiency virus 1 MeSH Prohlížeč
- peptidové fragmenty MeSH
HIV protease (PR) represents a prime target for rational drug design, and protease inhibitors (PI) are powerful antiviral drugs. Most of the current PIs are pseudopeptide compounds with limited bioavailability and stability, and their use is compromised by high costs, side effects, and development of resistant strains. In our search for novel PI structures, we have identified a group of inorganic compounds, icosahedral metallacarboranes, as candidates for a novel class of nonpeptidic PIs. Here, we report the potent, specific, and selective competitive inhibition of HIV PR by substituted metallacarboranes. The most active compound, sodium hydrogen butylimino bis-8,8-[5-(3-oxa-pentoxy)-3-cobalt bis(1,2-dicarbollide)]di-ate, exhibited a K(i) value of 2.2 nM and a submicromolar EC(50) in antiviral tests, showed no toxicity in tissue culture, weakly inhibited human cathepsin D and pepsin, and was inactive against trypsin, papain, and amylase. The structure of the parent cobalt bis(1,2-dicarbollide) in complex with HIV PR was determined at 2.15 A resolution by protein crystallography and represents the first carborane-protein complex structure determined. It shows the following mode of PR inhibition: two molecules of the parent compound bind to the hydrophobic pockets in the flap-proximal region of the S3 and S3' subsites of PR. We suggest, therefore, that these compounds block flap closure in addition to filling the corresponding binding pockets as conventional PIs. This type of binding and inhibition, chemical and biological stability, low toxicity, and the possibility to introduce various modifications make boron clusters attractive pharmacophores for potent and specific enzyme inhibition.
- MeSH
- aspartátové endopeptidasy chemie MeSH
- borany chemická syntéza chemie farmakologie MeSH
- HIV-proteasa chemie MeSH
- inhibitory HIV-proteasy chemická syntéza chemie farmakologie MeSH
- krystalografie rentgenová MeSH
- racionální návrh léčiv * MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- aspartátové endopeptidasy MeSH
- borany MeSH
- HIV-proteasa MeSH
- inhibitory HIV-proteasy MeSH
- p16 protease, Human immunodeficiency virus 2 MeSH Prohlížeč