Molecular Docking of SP40 Peptide towards Cellular Receptors for Enterovirus 71 (EV-A71)

Figures

• 

  Figure 1. Analysis of the predicted SP40 peptide. (A) Hydrophobic surface area. (B) Ability of SP40 peptide to passively penetrate across the lipid bilayer.

• 

  Figure 2. Generation of receptor SP40 peptide complex models resulting from global molecular docking via HEPEDOCK. The surface of the receptors and SP40 peptides are shown in wheat and blue colors, respectively. (A) Nucleolin, (B) Human cyclophilin, (C) Human galectin, (D) Fibronectin, (E) SCARB2, (F) DC-SIGN, (G) Annexin A2, (H) Human tryptophanyl-tRNA synthetase l, (I) Vimentin and (J) Human prohibitin.

• 

  Figure 3. Docking scores (Goldscore) of five top models of receptor-SP40 peptide complexes for each receptor generated by GOLD analysis.

• 

  Figure 4. Analysis of interactions between the SP40 peptide with nucleolin. (A) The binding pose of SP40 peptide on nucleolin receptor, with SP40 peptide being placed between the RNA binding (RBD) domains of nucleolin. (B) Residues in nucleolin involved in interactions with the SP40 peptide. Residues in the target receptors are shown as lines, while residues in the SP40 peptide are shown in sticks. Salt bridge and electrostatic interactions are in orange color, the conventional hydrogen bonds are shown in green dash line, carbon hydrogen bonds are in light green color, sulfur and hydrophobic interactions are in dark yellow and pink colors, respectively.

• 

  Figure 5. Analysis of interactions between SP40 peptide with annexin A2. (A) The binding pose of SP40 peptide on annexin A2 receptor. (B) Residues in annexin A2 involved in interactions with the SP40 peptide. Residues in the target receptors are shown as lines, while residues in the SP40 peptide are shown in sticks. Salt bridge and electrostatic interactions are in orange color, the conventional hydrogen bonds are shown in green dash line, carbon–hydrogen bonds are in light green color and hydrophobic interactions are in pink color.

• 

  Figure 6. Analysis of interactions between SP40 peptide with SCARB2. (A) The binding pose of SP40 peptide on SCARB2 receptor. (B) Residues in SCARB2 involved in interactions with the SP40 peptide. Residues in the target receptors are shown as lines, while residues in the SP40 peptide are shown in sticks. Salt bridge is in orange color, the conventional hydrogen bonds are shown in green dash line, carbon hydrogen bonds are in light green color, electrostatic interaction is in yellow and hydrophobic interaction is in purple color.

• 

  Figure 7. Analysis of interactions between SP40 peptide with human tryptophanyl-tRNA synthetase (hTrpRS). (A) The binding pose of SP40 peptide on hTrpRS receptor. (B) Residues in hTrpRS involved in interactions with the SP40 peptide. Residues in the target receptors are shown as lines, while residues in the SP40 peptide are shown in sticks. Electrostatic interactions are in orange color, the conventional hydrogen bonds are shown in green dash line, carbon hydrogen bonds are in light green color and hydrophobic interactions are in pink color.

• 

  Figure 8. Effects of L-SP40 peptide with specific anti-receptor antibodies on viral infectivity. RD cells were treated with antibodies targeting various receptors for 1 h followed by incubation with 100 µM L-SP40 peptide for 1 h. The L-SP40 peptide-treated cells were subsequently infected with EV-A71 (MOI = 0.1) for 1 h. Viral infectivity was determined by plaque assays. Error bars indicate the range of values obtained from three independent experiments (* p < 0.05, ** p < 0.01, ns = non-significant analyzed by t-test).