Neothramycin’s mode of action is widely known to be through the inhibition of DNA-dependent RNA and DNA polymerase.[1] The antibiotic activity of neothramycin was determined to be directly binding DNA by UV-Vis absorption measurements with differing concentrations of DNA and neothramycin.[8] The first studies of neothramycin began thinking that DNA was the chemoreceptor due to the inhibition of DNA and RNA polymerase that they observed when neothramycin was added.[9] The antibiotic activity, since these first studies, has been determined to be due to its direct binding of DNA.