The Effect Of Antioxidant On Pseudomonas Aeruginosa Pathogenic

Pseudomonas aeruginosa (PA), as a kind of nosocomial pathogen, the generation of oxidative stress is one of the reasons that result the deaths of infected patients. As the aerobic bacthria, when NO3-、NO2- as the bacterial terminal electron acceptor, P. aeruginosa can survive in the hypoxic environment such as biofilm and airway musus, which can protect its from killing of antibiotics, so the difficulty of healing the infectious disease is increasing. In this experiment, we studied the effect of antioxidant on P. aeruginosa pathogenicity, as well as the changed of its tolerance to drug under the condition of low oxygen.Glutathione (GSH), N-acetyl-L-Cysteine (NAC) and so on, as the important antioxidants of cells, serve as an important role in the body antioxidant defense system. By building a Glutathione systhetase gene (Glutathione systhetase, gshB) mutant PAO1(△gshB), we found that the production of PCN and biofilm (BF) of mutant was decreased, swimming, swarming, toxity and infection ability of its were also reduced. When GSH or NAC existing, there was an obvious decrease of them. It’s seems that there was a contradictory between intracellular GSH lacked and plused GSH, we speculate that under the both conditions the regulation of GSH in different ways, or there is a change of GSH form when its entering cells, nevertheless, comparing the effect of them to P.aeruginosa toxity, the additional GSH could reduce the infection ability of the bacteria, and has a protection to A549 cells.For the drug resistance of P. aeruginosa, under the condition of oxygen, the sensitivity of its to gentamicin, erythromycin, Kanamycin and Streptomycin sulphate could be reduced, and the sensitivity to Chloramphenicol, Ampicilin and Tetracycline could be increased when the GHS or NAC were plused. While under the condition of hypoxia, the MIC of gentamicin, Streptomycin sulphate and Azithromycin were increased 8,2, and 3-fold, and the MIC of Chloramphenicol, Ampicilin and Tetracycline with 5,2,8 and 4-fold decreased, respectively.Based on the existing experimental results and analysis, we hope to provide more important theoretical basis for clinical treatment of antioxidants, and expect to make it possible in the field of new drugs, so we can provide beneficial exploration to solve clinical infection.