HIV-1 reverse transcriptase variants: molecular modeling of Y181C, V106A, L100I, and K103N mutations with nonnucleoside inhibitors using Monte Carlo simulations in combination with a linear response method

The small-molecule 3G11 inhibits HIV-1 reverse transcription

The small-molecule 6-(tert-butyl)-4-phenyl-4-(trifluoromethyl)-1H,3H-1,3,5-triazin-2-one (3G11) inhibits HIV-1 replication in the human T cell line MT-2. Here, we showed that 3G11 specifically and potently blocks HIV-1 infection. By contrast, 3G11 did not block other retroviruses such as HIV-2, simian immunodeficiency virus (SIV_mac ), bovine immunodeficiency virus, feline immunodeficiency virus, equine infectious anemia virus, N-tropic murine leukemia virus, B-tropic murine leukemia virus, and Moloney murine leukemia virus. Analysis of DNA metabolism by real-time PCR revealed that 3G11 blocks the formation of HIV-1 late reverse transcripts during infection prior to the first-strand transfer step. In agreement, an in vitro assay revealed that 3G11 blocks the enzymatic activity of HIV-1 reverse transcriptase as strong as nevirapine. Docking of 3G11 to the HIV-1 reverse transcriptase enzyme suggested a direct interaction between residue L100 and 3G11. In agreement, an HIV-1 virus bearing the reverse transcriptase change L100I renders HIV-1 resistant to 3G11, which suggested that the reverse transcriptase enzyme is the viral determinant for HIV-1 sensitivity to 3G11. Although NMR experiments revealed that 3G11 binds to the HIV-1 capsid, functional experiments suggested that capsid is not the viral determinant for sensitivity to 3G11. Overall, we described a novel non-nucleoside reverse transcription inhibitor that blocks HIV-1 infection.

High potency of indolyl aryl sulfone nonnucleoside inhibitors towards drug-resistant human immunodeficiency virus type 1 reverse transcriptase mutants is due to selective targeting of different mechanistic forms of the enzyme

Indolyl aryl sulfone (IAS) nonnucleoside inhibitors have been shown to potently inhibit the growth of wild-type and drug-resistant human immunodeficiency virus type 1 (HIV-1), but their exact mechanism of action has not been elucidated yet. Here, we describe the mechanism of inhibition of HIV-1 reverse transcriptase (RT) by selected IAS derivatives. Our results showed that, depending on the substitutions introduced in the IAS common pharmacophore, these compounds can be made selective for different enzyme-substrate complexes. Moreover, we showed that the molecular basis for this selectivity was a different association rate of the drug to a particular enzymatic form along the reaction pathway. By comparing the activities of the different compounds against wild-type RT and the nonnucleoside reverse transcriptase inhibitor-resistant mutant Lys103Asn, it was possible to hypothesize, on the basis of their mechanism of action, a rationale for the design of drugs which could overcome the steric barrier imposed by the Lys103Asn mutation.