Expression data from QdNOs treated Escherichia coli

Cyadox(CYA), as a new species of Quinoxaline 1, 4-dioxides and olaquindox(OLA) both showed higher antibacterial activity under anaerobic incubation. Microarray was used for global gene expression studies, which were further confirmed by real-time PCR. Cyadox and olaquindox mainly stimulated the expression of DNA repair genes as a response to the DNA damage. The induced gene sbmC was found to provide partial protection against the antibiotics of gyrase inhibitors like the quinolones and the ruvAB helped remove the topoisomerase IV-DNA cleavage complex caused by some type IIA topoisomerase poison antibiotics. It was inferred that the radical intermediate of cyadox reduction under anaerobic condition was responsible for the poison effect of IIA topoisomerases, which brought about DNA double stand breaks and other DNA damages in E. coli. We applied subinhibitory concentrations (concentrations that cause little growth inhibition) of two drus with the goal of observing antibiotic-specific primary expression profiles, and higher concentrations of drugs had been shown to cause a broader effect on cellular processes, thereby giving more complex response patterns and dose-specific effects could be examined.To the end, drugs were added to a final concentration of 0.5MIC(2) and MBC(3) for cyadox, and MIC(4) and MBC(5) for olaquindox, respectively. Control with 1% (vol/vol) DMSO(1) was grown in parallel.