title: Phytoestrogen genistein as an anti-staphylococcal agent.
abstract: The soybean-derived isoflavone genistein has been shown to exert beneficial effects on many disorders, including cancer and cardiovascular diseases. The effects of genistein on mammalian cells are mediated by its abilities to inhibit topoisomerase II and protein tyrosine kinase. In order to examine the potential antibacterial activities of genistein, we incubated the bacteria with various concentrations of this compound for different periods of time and assessed the viable counts. Exposure to genistein exhibited an inhibitory effect on all staphylococcal strains tested, including methicillin-resistant strains. Furthermore, the growth of Streptococcus pasteurianus, Bacillus cereus, and Helicobacter pylori was clearly inhibited by genistein, whereas Escherichia coli growth was not suppressed. Daidzein, which is structurally similar to genistein, but deficient in topoisomerase II inhibitory activity, also inhibited the growth of Staphylococcus aureus, albeit with lower potency than genistein. Our results indicate that genistein exerts potent antibacterial properties in vitro, which are possibly mediated by the stabilization of the covalent topoisomerase II-DNA cleavage complex.
authors.affiliation: Department of Rheumatology and Inflammation Research, University of Göteborg, Guldhedsgatan 10A, 413 46, Gothenburg, Sweden. margareta.verdrengh@rheuma.gu.se
authors.forename: Margareta
authors.initials: M
authors.lastname: Verdrengh
authors.forename: L Vincent
authors.initials: LV
authors.lastname: Collins
authors.forename: Philip
authors.initials: P
authors.lastname: Bergin
authors.forename: Andrej
authors.initials: A
authors.lastname: Tarkowski
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology; D005260:Female; D019833:Genistein / Q000494:pharmacology*; D007529:Isoflavones / Q000494:pharmacology; D008712:Methicillin / Q000494:pharmacology; D016106:Methicillin Resistance; D051379:Mice; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D004968:Estrogens, Non-Steroidal; D007529:Isoflavones; C004742:daidzein; D019833:Genistein; D008712:Methicillin