Molecular modeling study on the allosteric inhibition mechanism of HIV-1 integrase by LEDGF/p75 binding site inhibitors

PLoS One. 2014 Mar 5;9(3):e90799. doi: 10.1371/journal.pone.0090799. eCollection 2014.

Abstract

HIV-1 integrase (IN) is essential for the integration of viral DNA into the host genome and an attractive therapeutic target for developing antiretroviral inhibitors. LEDGINs are a class of allosteric inhibitors targeting LEDGF/p75 binding site of HIV-1 IN. Yet, the detailed binding mode and allosteric inhibition mechanism of LEDGINs to HIV-1 IN is only partially understood, which hinders the structure-based design of more potent anti-HIV agents. A molecular modeling study combining molecular docking, molecular dynamics simulation, and binding free energy calculation were performed to investigate the interaction details of HIV-1 IN catalytic core domain (CCD) with two recently discovered LEDGINs BI-1001 and CX14442, as well as the LEDGF/p75 protein. Simulation results demonstrated the hydrophobic domain of BI-1001 and CX14442 engages one subunit of HIV-1 IN CCD dimer through hydrophobic interactions, and the hydrophilic group forms hydrogen bonds with HIV-1 IN CCD residues from other subunit. CX14442 has a larger tert-butyl group than the methyl of BI-1001, and forms better interactions with the highly hydrophobic binding pocket of HIV-1 IN CCD dimer interface, which can explain the stronger affinity of CX14442 than BI-1001. Analysis of the binding mode of LEDGF/p75 with HIV-1 IN CCD reveals that the LEDGF/p75 integrase binding domain residues Ile365, Asp366, Phe406 and Val408 have significant contributions to the binding of the LEDGF/p75 to HIV1-IN. Remarkably, we found that binding of BI-1001 and CX14442 to HIV-1 IN CCD induced the structural rearrangements of the 140 s loop and oration displacements of the side chains of the three conserved catalytic residues Asp64, Asp116, and Glu152 located at the active site. These results we obtained will be valuable not only for understanding the allosteric inhibition mechanism of LEDGINs but also for the rational design of allosteric inhibitors of HIV-1 IN targeting LEDGF/p75 binding site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allosteric Regulation / drug effects
  • Amino Acid Motifs
  • Binding Sites
  • Catalytic Domain
  • HIV Integrase / chemistry*
  • HIV Integrase Inhibitors / chemistry
  • HIV Integrase Inhibitors / pharmacology*
  • Intercellular Signaling Peptides and Proteins / chemistry*
  • Ligands
  • Models, Molecular*
  • Molecular Docking Simulation
  • Molecular Dynamics Simulation
  • Protein Binding / drug effects
  • Protein Multimerization / drug effects
  • Static Electricity
  • Thermodynamics

Substances

  • HIV Integrase Inhibitors
  • Intercellular Signaling Peptides and Proteins
  • Ligands
  • lens epithelium-derived growth factor
  • HIV Integrase
  • p31 integrase protein, Human immunodeficiency virus 1

Grants and funding

This work was supported by the National Natural Science Foundation of China (Grant No 21175063) and the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT: IRT1137). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.