Identification of Zika Virus Inhibitors Using Homology Modeling and Similarity-Based Screening to Target Glycoprotein E

Biochemistry. 2020 Oct 6;59(39):3709-3724. doi: 10.1021/acs.biochem.0c00458. Epub 2020 Sep 17.

Abstract

The World Health Organization has designated Zika virus (ZIKV) as a dangerous, mosquito-borne pathogen that can cause severe developmental defects. The primary goal of this work was identification of small molecules as potential ZIKV inhibitors that target the viral envelope glycoprotein (ZIKV E) involved in membrane fusion and viral entry. A homology model of ZIKV E containing the small molecule β-octyl glucoside (BOG) was constructed, on the basis of an analogous X-ray structure from dengue virus, and >4 million commercially available compounds were computationally screened using the program DOCK6. A key feature of the screen involved the use of similarity-based scoring to identify inhibitor candidates that make similar interaction energy patterns (molecular footprints) as the BOG reference. Fifty-three prioritized compounds underwent experimental testing using cytotoxicity, cell viability, and tissue culture infectious dose 50% (TCID50) assays. Encouragingly, relative to a known control (NITD008), six compounds were active in both the cell viability assay and the TCID50 infectivity assay, and they showed activity in a third caspase activity assay. In particular, compounds 8 and 15 (tested at 25 μM) and compound 43 (tested at 10 μM) appeared to provide significant protection to infected cells, indicative of anti-ZIKV activity. Overall, the study highlights how similarity-based scoring can be leveraged to computationally identify potential ZIKV E inhibitors that mimic a known reference (in this case BOG), and the experimentally verified hits provide a strong starting point for further refinement and optimization efforts.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antiviral Agents / chemistry*
  • Antiviral Agents / pharmacology*
  • Chlorocebus aethiops
  • Drug Discovery
  • Humans
  • Molecular Docking Simulation
  • Small Molecule Libraries / chemistry*
  • Small Molecule Libraries / pharmacology*
  • Vero Cells
  • Viral Envelope Proteins / antagonists & inhibitors*
  • Viral Envelope Proteins / metabolism
  • Virus Internalization / drug effects
  • Zika Virus / drug effects*
  • Zika Virus / physiology
  • Zika Virus Infection / drug therapy
  • Zika Virus Infection / metabolism
  • Zika Virus Infection / virology

Substances

  • Antiviral Agents
  • Small Molecule Libraries
  • Viral Envelope Proteins