钾离子与渗透胁迫下细菌DNA超螺旋结构的变化

Potassium ions and changes in bacterial DNA supercoiling under osmotic stress.

作者信息

Meury J, Kohiyama M

机构信息

Institut Jacques Monod, Paris, France.

出版信息

FEMS Microbiol Lett. 1992 Dec 1;78(2-3):159-64. doi: 10.1016/0378-1097(92)90018-j.

DOI:10.1016/0378-1097(92)90018-j

PMID:1490596

Abstract

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.

摘要

当大肠杆菌转移至高渗环境时，它会瞬时提高[ATP]/[ADP]比值以及质粒DNA的负超螺旋水平。在此我们报告，一个缺失所有可饱和钾离子转运系统的突变体在受到渗透压上升冲击时会增加质粒DNA的负超螺旋，但无法进一步使DNA松弛。突变体dnaK756的表现与钾离子转运突变体相似。