title: Antivirus agent, Ro 09-0410, binds to rhinovirus specifically and stabilizes the virus conformation.
abstract: The antiviral mechanisms of Ro 09-0410 (4'-ethoxy-2'-hydroxy-4,6'-dimethoxychalcone), which inactivates rhinovirus exclusively, have been investigated. It was suggested that Ro 09-0410 bound to human rhinovirus type 2 (HRV-2) and made it inactive, since the reduced infectivity was completely restored to original levels by extraction of the agent with chloroform [H. Ishitsuka, Y. Ninomiya, C. Ohsawa, M. Fujiu, and Y. Suhara (1982) Antimicrob. Agents Chemother. 22, 617-621]. This was confirmed using radioactively labeled Ro 09-0410 and HRV-2. HRV-2 was inactive while bound to the agent, whereas a subline of HRV-2 resistant to the agent had no binding site for the agent. Ro 09-0410 appeared to bind to some specific site(s) on the virion of susceptible virus strains. Treatment of rhinovirus at pH 5 or 56 degrees caused a change of the virion size and greatly reduced its infectivity. Ro 09-0410 could no longer bind to HRV-2 after such treatment. On the other hand, when the virion bound with Ro 09-0410 was treated at pH 5 or 56 degrees, the Ro 09-0410 remained bound and the conformational alteration of the virion did not take place. Furthermore, Ro 09-0410 protected HRV-2 from the reduction of infectivity caused by mild acid or heat treatment, as revealed by infectivity measurements after extraction of the agent with chloroform. These results suggest that Ro 09-0410 binds to the HRV-2 virion and prevents viral replication in the cell.
mesh_terms: D000998:Antiviral Agents / Q000378:metabolism* / Q000494:pharmacology; D001665:Binding Sites; D002213:Capsid / Q000378:metabolism; D002599:Chalcone / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D047188:Chalcones; D006367:HeLa Cells; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011427:Propiophenones / Q000378:metabolism*; D012229:Rhinovirus / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000998:Antiviral Agents; D047188:Chalcones; D011427:Propiophenones; D002599:Chalcone; C036425:Ro 09-0410