Novobiocin is a natural antibiotic produced by a member of the genus Streptomyces. It belongs to the class of antibiotics called Aminocoumarins and is considered a narrow-spectrum antibiotic.
Its mode of action is disabling the bacterial DNA Gyrase enzyme. This is one of the topoisomerases that is responsible for changing the 3-D structure of DNA during its unpackaging for DNA replication and transcription and repackaging for distribution of the two daughter genomes into the two daughter cells during growth. Novobiocin inhibits bacterial DNA Gyrase by binding to the GyrB subunit, which harvests energy from ATP to drive gyrase activity. Without normal use of ATP possible, the gyrase does not function and cells division in halted – cells die.