Effect of Zinc and Other Chemical Agents on Foot-and-Mouth Disease Virus Replication

Chemical agents reported to inhibit the growth of various ribonucleic acid and deoxyribonucleic acid viruses were tested against foot-and-mouth disease virus in cell culture. These included Zn2+ , aurintricarboxylic acid, polyribocytidylic acid, polyriboinosinic acid, phosphonoacetic acid, and the viral contact inactivatorN -methyl isatin β-thiosemicarbazone alone and with CuSO4 . The most effective agent, Zn2+ , inhibited foot-and-mouth disease virus production in primary calf kidney cells by 1 log unit at 0.05 mM Zn2+ and completely at 0.50 mM. Zinc was inhibitory even when added late in infection and was nontoxic to uninfected cells as measured by protein and nucleic acid syntheses. Polyacrylamide gel patterns of [35 S]methionine-labeled, virus-specific proteins showed increasing amounts of higher-molecular-weight material, in accord with reports that Zn2+ inhibits post-translational cleavages of other picornavirus precursor polypeptides.