A small compound targeting the interaction between nonstructural proteins 2B and 3 inhibits dengue virus replication.
The non-structural protein NS2B/NS3 serine-protease complex of the dengue virus (DENV) is required for the maturation of the viral polyprotein. Dissociation of the NS2B cofactor from NS3 diminishes the enzymatic activity of the complex. In this study, we identified a small molecule inhibitor that interferes with the interaction between NS2B and NS3 using structure-based screening and a cell-based viral replication assay. A library containing 661,417 small compounds derived from the Molecular Operating Environment lead-like database was docked to the NS2B/NS3 structural model. Thirty-nine compounds with high scores were tested in a secondary screening using a cell-based viral replication assay. SK-12 was found to inhibit replication of all DENV serotypes (EC50=0.74-4.92 μM). In silico studies predicted that SK-12 pre-occupies the NS2B-binding site of NS3. Steady-state kinetics using a fluorogenic short peptide substrate demonstrated that SK-12 is a noncompetitive inhibitor against the NS2B/NS3 protease. Inhibition to Japanese encephalitis virus by SK-12 was relatively weak (EC50=29.81 μM), and this lower sensitivity was due to difference in amino acid at position 27 of NS3. SK-12 is the promising small-molecule inhibitor that targets the interaction between NS2B and NS3.
Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
Sabar
S
Pambudi
Norihito
N
Kawashita
Supranee
S
Phanthanawiboon
Magot Diata
MD
Omokoko
Promsin
P
Masrinoul
Akifumi
A
Yamashita
Kriengsak
K
Limkittikul
Teruo
T
Yasunaga
Tatsuya
T
Takagi
Kazuyoshi
K
Ikuta
Takeshi
T
Kurosu
D000998:Antiviral Agents / Q000494:pharmacology*; D003198:Computer Simulation; D003715:Dengue / Q000188:drug therapy* / Q000201:enzymology; D006801:Humans; D008956:Models, Chemical; D009284:Naphthols / Q000494:pharmacology*; D011487:Protein Conformation; D057057:Serine Proteases / Q000737:chemistry*; D054852:Small Molecule Libraries / Q000494:pharmacology*; D013449:Sulfonamides / Q000494:pharmacology*; D017361:Viral Nonstructural Proteins / Q000737:chemistry*; D014779:Virus Replication / Q000187:drug effects*
C588036:2-((1-hydroxy-4-(4-methyl-3-nitrobenzenesulfonamido)naphthalen-2-yl)sulfanyl)acetic acid; D000998:Antiviral Agents; D009284:Naphthols; D054852:Small Molecule Libraries; D013449:Sulfonamides; D017361:Viral Nonstructural Proteins; D057057:Serine Proteases
Antiviral; Dengue virus; Infectious diseases; NS2B/NS3 protease; Re-emerging infection