Inhibitors of DNA polymerases of murine leukemia viruses: activity of ethidium bromide.

Ethidium bromide, compared on a molar basis, was a more effective inhibitor of the DNA polymerases of the Rauscher and Moloney murine leukemia viruses than either 4-N-demethylrifampicin or 4-N-benzyldemethylrifampicin. Daunomycin inhibited the polymerases weakly, and chromomycin A(3) inhibited almost not at all. 4-N-Benzyldemethylrifampicin was a more active inhibitor than the 4-N-demethyl congener.