title: Curing bacteria of antibiotic resistance: reverse antibiotics, a novel class of antibiotics in nature.
abstract: By screening cultures of soil bacteria, we re-discovered an old antibiotic (nybomycin) as an antibiotic with a novel feature. Nybomycin is active against quinolone-resistant Staphylococcus aureus strains with mutated gyrA genes but not against those with intact gyrA genes against which quinolone antibiotics are effective. Nybomycin-resistant mutant strains were generated from a quinolone-resistant, nybomycin-susceptible, vancomycin-intermediate S. aureus (VISA) strain Mu 50. The mutants, occurring at an extremely low rate (<1 × 10(-11)/generation), were found to have their gyrA genes back-mutated and to have lost quinolone resistance. Here we describe nybomycin as the first member of a novel class of antibiotics designated 'reverse antibiotics'.
authors.affiliation: Department of Bacteriology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. khiram06@juntendo.ac.jp
authors.forename: Keiichi
authors.initials: K
authors.lastname: Hiramatsu
authors.forename: Masayuki
authors.initials: M
authors.lastname: Igarashi
authors.forename: Yuh
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Tadashi
authors.initials: T
authors.lastname: Baba
authors.forename: Maya
authors.initials: M
authors.lastname: Umekita
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Akamatsu
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D027081:DNA Gyrase / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000187:drug effects*; D006801:Humans; D008712:Methicillin / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000235:genetics; D008826:Microbial Sensitivity Tests; D009154:Mutation; D015363:Quinolones / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics; D014640:Vancomycin / Q000494:pharmacology; D020713:Vancomycin Resistance / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D015363:Quinolones; D014640:Vancomycin; D027081:DNA Gyrase; C005316:nybomycin; D008712:Methicillin