aminocoumarin antibiotic novobiocin cathomycin PubChem:54675769 streptonivicin ARO:3000111 CAS:303-81-1 antibiotic_resistance ChEMBL:CHEMBL36506 ChEBI:28368 Novobiocin is an aminocoumarin antibiotic produced by Streptomyces spheroides and Streptomyces niveus, and binds DNA gyrase subunit B inhibiting ATP-dependent DNA supercoiling.