Lomofungin, an inhibitor of deoxyribonucleic acid-dependent ribonucleic acid polymerases.

Lomofungin, an antibiotic active against fungi, yeasts, and bacteria, was found to be a potent inhibitor of purified Escherichia coli deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase. It prevents RNA synthesis by a direct interaction with the polymerase and not with the template or substrate; chain elongation is halted promptly. Three DNA-dependent RNA polymerases isolated from Saccharomyces strain 1016 were also sensitive to the antibiotic. Lomofungin does not appear to react generally with proteins, as bovine serum albumin did not prevent the inhibitory effect and numerous other enzymes were not affected by lomofungin.