ST-246 is a key antiviral to inhibit the viral F13L phospholipase, one of the essential proteins for orthopoxvirus wrapping. 2015

Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
Rega Institute, Laboratory of Virology and Chemotherapy, KU Leuven, Leuven, Belgium sophie.duraffour@rega.kuleuven.be.

OBJECTIVE ST-246 is one of the key antivirals being developed to fight orthopoxvirus (OPV) infections. Its exact mode of action is not completely understood, but it has been reported to interfere with the wrapping of infectious virions, for which F13L (peripheral membrane protein) and B5R (type I glycoprotein) are required. Here we monitored the appearance of ST-246 resistance to identify its molecular target. METHODS Vaccinia virus (VACV), cowpox virus (CPXV) and camelpox virus (CMLV) with reduced susceptibility to ST-246 were selected in cell culture and further characterized by antiviral assays and immunofluorescence. A panel of recombinant OPVs was engineered and a putative 3D model of F13L coupled with molecular docking was used to visualize drug-target interaction. The F13L gene of 65 CPXVs was sequenced to investigate F13L amino acid heterogeneity. RESULTS Amino acid substitutions or insertions were found in the F13L gene of six drug-resistant OPVs and production of four F13L-recombinant viruses confirmed their role(s) in the occurrence of ST-246 resistance. F13L, but not B5R, knockout OPVs showed resistance to ST-246. ST-246 treatment of WT OPVs delocalized F13L- and B5R-encoded proteins and blocked virus wrapping. Putative modelling of F13L and ST-246 revealed a probable pocket into which ST-246 penetrates. None of the identified amino acid changes occurred naturally among newly sequenced or NCBI-derived OPV F13L sequences. CONCLUSIONS Besides demonstrating that F13L is a direct target of ST-246, we also identified novel F13L residues involved in the interaction with ST-246. These findings are important for ST-246 use in the clinic and crucial for future drug-resistance surveillance programmes.

UI MeSH Term Description Entries
D008826 Microbial Sensitivity Tests Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses). Bacterial Sensitivity Tests,Drug Sensitivity Assay, Microbial,Minimum Inhibitory Concentration,Antibacterial Susceptibility Breakpoint Determination,Antibiogram,Antimicrobial Susceptibility Breakpoint Determination,Bacterial Sensitivity Test,Breakpoint Determination, Antibacterial Susceptibility,Breakpoint Determination, Antimicrobial Susceptibility,Fungal Drug Sensitivity Tests,Fungus Drug Sensitivity Tests,Sensitivity Test, Bacterial,Sensitivity Tests, Bacterial,Test, Bacterial Sensitivity,Tests, Bacterial Sensitivity,Viral Drug Sensitivity Tests,Virus Drug Sensitivity Tests,Antibiograms,Concentration, Minimum Inhibitory,Concentrations, Minimum Inhibitory,Inhibitory Concentration, Minimum,Inhibitory Concentrations, Minimum,Microbial Sensitivity Test,Minimum Inhibitory Concentrations,Sensitivity Test, Microbial,Sensitivity Tests, Microbial,Test, Microbial Sensitivity,Tests, Microbial Sensitivity
D008958 Models, Molecular Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures. Molecular Models,Model, Molecular,Molecular Model
D009154 Mutation Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations. Mutations
D010740 Phospholipases A class of enzymes that catalyze the hydrolysis of phosphoglycerides or glycerophosphatidates. EC 3.1.-. Lecithinases,Lecithinase,Phospholipase
D010948 Viral Plaque Assay Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE. Bacteriophage Plaque Assay,Assay, Bacteriophage Plaque,Assay, Viral Plaque,Assays, Bacteriophage Plaque,Assays, Viral Plaque,Bacteriophage Plaque Assays,Plaque Assay, Bacteriophage,Plaque Assay, Viral,Plaque Assays, Bacteriophage,Plaque Assays, Viral,Viral Plaque Assays
D011485 Protein Binding The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments. Plasma Protein Binding Capacity,Binding, Protein
D011487 Protein Conformation The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain). Conformation, Protein,Conformations, Protein,Protein Conformations
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D000998 Antiviral Agents Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly. Antiviral,Antiviral Agent,Antiviral Drug,Antivirals,Antiviral Drugs,Agent, Antiviral,Agents, Antiviral,Drug, Antiviral,Drugs, Antiviral

Related Publications

Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
January 2008, Antiviral therapy,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
January 2013, PloS one,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
April 2007, The American journal of tropical medicine and hygiene,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
September 2011, Journal of virology,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
May 2008, Antimicrobial agents and chemotherapy,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
May 2011, Future virology,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
March 2013, Antiviral research,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
February 2007, Antimicrobial agents and chemotherapy,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
November 2004, Journal of virology,
Sophie Duraffour, and María M Lorenzo, and Gudrun Zöller, and Dimitri Topalis, and Doug Grosenbach, and Dennis E Hruby, and Graciela Andrei, and Rafael Blasco, and Hermann Meyer, and Robert Snoeck
September 2012, Antimicrobial agents and chemotherapy,
Copied contents to your clipboard!