Anti-dengue virus activity of scytovirin and evaluation of point mutation effects by molecular dynamics and binding free energy calculations

Biochem Biophys Res Commun. 2017 Aug 26;490(3):1033-1038. doi: 10.1016/j.bbrc.2017.06.160. Epub 2017 Jun 27.

Abstract

The absence of a specific treatment against DENV has led to intensive research into developing strategies for curing the infection. One lectin with high antiviral activity is scytovirin, which was isolated from the cyanobacterium Scytonema varium and has proven activity against HIV and Zaire Ebola Virus. To achieve the results presented here, we tested the affinity of full-length scytovirin, SD1 and SD2 separately, and six SD1 mutants for DENV glycoprotein E carbohydrate by Molecular Dynamics (MD) simulations and binding free energy calculations. It was possible to identify the key residues for protein-ligand interaction such as Glu10, Ala11, Pro17, Ans18, Arg30, Thr41, Ser42 and Arg43, which also has importance action against HIV. All binding free energy calculations showed negative values to ΔGbind of protein-DENV carbohydrate complexation. Additionally, these results are similar to the values of scytovirin and HIV gp120 carbohydrate complexation (-32.20 kcal/mol). Furthermore, we found that SD1 individually has more affinity to the carbohydrate and the Asn9, Glu10, Asn18, Arg30 and Arg43 demonstrated an important role in this matter. We also found that mutant G48R has better affinity (-34.10 kcal/mol) for the DENV carbohydrate than the wild type protein (-27.15 kcal/mol).

Keywords: Antiviral activity; Binding free energy; Dengue virus; Molecular dynamics; Scytovirin.

MeSH terms

  • Antiviral Agents / chemistry
  • Antiviral Agents / metabolism
  • Antiviral Agents / pharmacology*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / pharmacology*
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics
  • Carrier Proteins / pharmacology*
  • Cyanobacteria / chemistry*
  • Cyanobacteria / genetics
  • Dengue / drug therapy*
  • Dengue / virology
  • Dengue Virus / chemistry
  • Dengue Virus / drug effects*
  • Dengue Virus / metabolism
  • Glycoproteins / chemistry
  • Glycoproteins / metabolism
  • Humans
  • Lectins / chemistry
  • Lectins / genetics
  • Lectins / pharmacology*
  • Membrane Proteins
  • Molecular Dynamics Simulation
  • Point Mutation
  • Protein Binding
  • Thermodynamics
  • Viral Envelope Proteins / chemistry
  • Viral Envelope Proteins / metabolism

Substances

  • Antiviral Agents
  • Bacterial Proteins
  • Carrier Proteins
  • Glycoproteins
  • Lectins
  • Membrane Proteins
  • Viral Envelope Proteins
  • scytovirin protein, S varium