Background: Reverse Transcriptase (RT) of immunodeficiency virus type-1 (HIV-1)
remains an essential target for new antiretroviral therapies. Non-nucleoside reverse transcriptase
inhibitors (or NNRTIs) constitute a major class of RT inhibitors whose characterization is essential.
Introduction: Several biochemical, biological, and biophysical methods have been previously used
to analyze the biological effects of NNRTIs. We explored here the use of surface plasmonic resonance
to characterize the affinity of RT towards selected NNRTIs and compared the results with
those obtained with in vitro and in cellulo assays.
Methods: The solubility and stability in buffers of the tested NNRTIs were assessed by spectrophotometry
and fluorescence. Surface plasmonic resonance experiments to study direct NNRTIs binding
to immobilized RT and intramolecular quenching of RT tryptophan fluorescence were used to determine
the KA association constants (= 1/KD) between RT and the inhibitors. The in vitro inhibition
constants of RT were determined using kinetics and the effects on three other potential targets (proteasome,
HIV-1 integrase, and HIV-1 protease) were analyzed.
Results: The results obtained with two typical molecules belonging to our previous N-hydroxyureido
acylnucleoside derivatives series using the above biophysical assays matched those obtained in in
vitro and previous in cellulo assays.
Conclusion: Surface plasmonic resonance provides reliable thermodynamic information on the interaction
of RT with NNRTIs and appears as a useful method for understanding their inhibitory