title: Baicalein suppresses the SOS response system of Staphylococcus aureus induced by ciprofloxacin.
abstract: Numerous antibiotics can induce an SOS repair system in bacteria that leads to antibiotic-resistant mutation of the bacterium. Therefore, searching for drugs that can prevent the SOS response and thus improve the long-term viability of some antibiotics is important. In this study, we aimed to detect the suppressive effects of baicalein on the SOS system and rifampin-resistant mutation in Staphylococcus aureus. We determined the reactive oxygen species (ROS) formation and intracellular ATP level in S. aureus with baicalein treatment to investigate the mechanisms involved in its effects on the SOS system. The results showed that baicalein was a potent inhibitor of the expression of the SOS genes RecA, LexA and SACOL1400. The rifampin-resistant mutation rate of S. aureus induced by ciprofloxacin was significantly reduced after treatment with baicalein. Treatment with baicalein led to a significant decrease in intracellular reactive oxygen species (ROS) formation and ATP level. Our findings indicate that baicalein may be an SOS-response inhibitor in S. aureus through inhibiting ROS formation and ATP production and may be used to prevent excessive mutation induced by antibiotics.
authors.affiliation: Pharmacology Department, Shantou University Medical College, Shantou, Guangdong, RP China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Peng
authors.forename: Shuqin
authors.initials: S
authors.lastname: Zhou
authors.forename: Fen
authors.initials: F
authors.lastname: Yao
authors.forename: Bing
authors.initials: B
authors.lastname: Hou
authors.forename: Yuanchun
authors.initials: Y
authors.lastname: Huang
authors.forename: Dexing
authors.initials: D
authors.lastname: Hua
authors.forename: Yanshan
authors.initials: Y
authors.lastname: Zheng
authors.forename: Yuanshu
authors.initials: Y
authors.lastname: Qian
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000890:Anti-Infective Agents / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002939:Ciprofloxacin / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D044950:Flavanones / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D017382:Reactive Oxygen Species / Q000378:metabolism; D011938:Rec A Recombinases / Q000235:genetics / Q000378:metabolism; D013014:SOS Response, Genetics / Q000187:drug effects*; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000378:metabolism; D000099160:LexA Repressor Protein
chemical_list: D000255:Adenosine Triphosphate; D000890:Anti-Infective Agents; D000975:Antioxidants; D001426:Bacterial Proteins; D002939:Ciprofloxacin; D044950:Flavanones; D017382:Reactive Oxygen Species; D011938:Rec A Recombinases; D012697:Serine Endopeptidases; D000099160:LexA Repressor Protein; C006680:baicalein