Investigation of oxidative stress related genes in Escherichia coli metal resistance

The purpose of this work is to determine the roles of the oxidative stres genes in the survival of Escherichia coli under the effect of some metals that cause stress.Escherichia coli has to cope with the stress factor in nature. Oxidative stress is a common stres factor that microorganisms often encounter in nature and related to their aerobic metabolisms. They have various enzymatic and nonenzymatic protection mechanisms to overcome this stress. In this study, to research of the roles of sodA, sodB, sodC, katE, katG, ahpC, zwf, btuE enzymes and oxyR, soxR, soxS regulation genes on the protection of Escherichia coli again oxidative stres the relation with metals, mutant bacteria were used. The mutant genes of Escherichia coli BW25113 obtained from Japan National Genetic Center were transfered with P1 transduction Escherichia coli W3110 bacteria, and E. coli W3110 that have a mutant gene were obtained. Plazmits that obtained from Japan were transfered to these mutants for complementation tests. For the analyses of metal resistance of these genes, Minimal Inhibitory Concentration tests in microplates of Cu, Zn, Ni, Co, Mn, Al, Pb, Cd, As, Cr, Mo, Hg metals, the viable experiments in metal existence with the half of Minimal Inhibitory Concentration values in phosphate buffer, the reproduction tests are carried out with various amount of bacteria in nutrient agar with the concentration of different metals. At the end of the studies, the same tests are repeated with the mutants that have the plazmit transformation genes for the accuracy of the genes that play an important roles. At the end of the study, the role of the oxidative stress genes relation with the metal stress, and what genes play roles on the metal resistance under different conditions were determined. It is aimed to contribute global mechanisms to protect againts metal stress in literature with the help of this project. Keywords: Escherichia coli, metal stress, reactive oxygen radicals