[The role of putrescine and the energy state of Escherichia coli in regulation of DNA topology during adaptation to oxidative stress].
An exponential-phase culture of E. coli responded to the addition of H2O2 by a decrease in DNA supercoiling induced by the lowering of the energy status of cells, potassium leakage, and breaking of polynucleotide chains. Extending the time of exposure of E. coli cells to hydrogen peroxide led to an increase in the intracellular pools of putrescine and potassium, promotion of cellular energy status, and the restoration of DNA supercoiling to values much in excess of the prestress level. The subsequent stabilization of the intracellular putrescine pool was accompanied by a release of this polyamine from the cell. Based on these results and those available in the literature, a mechanism of E. coli adaptation to oxidative stress is suggested that assigns roles to putrescine, potassium, and cellular energy status.
Tkachenko
A G
AG
Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Perm, Russia.
Pshenichnov
M R
MR
Salakhetdinova
O Ia
OIa
Nesterova
L Iu
LIu
D004261:DNA Replication; D004269:DNA, Bacterial / Q000235:genetics*; D004734:Energy Metabolism; D004926:Escherichia coli / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000633:toxicity; D016877:Oxidants / Q000633:toxicity; D018384:Oxidative Stress; D011188:Potassium / Q000502:physiology; D011700:Putrescine / Q000502:physiology*
D004269:DNA, Bacterial; D016877:Oxidants; D006861:Hydrogen Peroxide; D011188:Potassium; D011700:Putrescine
Rol' putresysina i énergeticheskogo sostoianiia Escherichia coli v re guliatsii topologii DNK pri adaptatsii k okislitel'nomu stressu.