[Topological changes in DNA as a reflection of adaptation of Escherichia coli to oxidative stress under glucose starvation and transition to growth].
Changes in the topological state of DNA occur in a starving Escherichia coli culture under oxidative stress caused by the addition of hydrogen peroxide. The addition of a carbon and energy source to this culture results in a second stress reaction. This supports previous data indicating that different mechanisms are responsible for the cell defense against oxidative stress in exponential and starving E. coli cultures. Polyamine synthesis is involved in the cell adaptation to the stress. Putrescine binding to DNA and its dissociation seem to modulate the DNA topological state, which regulates the expression of the adaptive genes. An increase in the activity of the polyamine-synthesizing system in response to oxidative stress leads to a putrescine flux across the cytoplasmic membrane, due to which the antioxidant activity of putrescine protects the membrane phospholipids and contributes to the restoration of the cell energy-generating function.
Salakhetdinova
O Ia
OIa
Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Perm, Russia.
Pshenichnov
M R
MR
Nesterova
L Iu
LIu
Dracheva
N A
NA
Tkachenko
A G
AG
D000222:Adaptation, Physiological; D003470:Culture Media; D004269:DNA, Bacterial / Q000737:chemistry* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D005947:Glucose / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism; D009690:Nucleic Acid Conformation; D018384:Oxidative Stress; D011700:Putrescine / Q000378:metabolism
D003470:Culture Media; D004269:DNA, Bacterial; D008563:Membrane Lipids; D005947:Glucose; D011700:Putrescine