Potassium ions and changes in bacterial DNA supercoiling under osmotic stress.
Escherichia coli transiently increases both the [ATP]/[ADP] ratio and the negative supercoiling of plasmid DNA when it is shifted to high osmolarity. Here we report that a mutant lacking all saturable K+ transport systems increases the negative supercoiling of the plasmid DNA under upshock but cannot further relax DNA. The mutant dnaK756 behaves like the K+ transport mutant.
Meury
J
J
Institut Jacques Monod, Paris, France.
Kohiyama
M
M
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism*; D004278:DNA, Superhelical / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D017136:Ion Transport / Q000235:genetics; D009154:Mutation; D009997:Osmotic Pressure; D010957:Plasmids; D011188:Potassium / Q000378:metabolism*
D004269:DNA, Bacterial; D004278:DNA, Superhelical; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D011188:Potassium