Potassium/proton antiport system of Escherichia coli.

  title={Potassium/proton antiport system of Escherichia coli.},
  author={Martha V. Radchenko and Kimihiro Tanaka and Rungaroon Waditee and Sawako Oshimi and Yasutomo Matsuzaki and Masahiro Fukuhara and Hiroshi Kobayashi and Teruhiro Takabe and Tatsunosuke Nakamura},
  journal={The Journal of biological chemistry},
  volume={281 29},
The intracellular level of potassium (K(+)) in Escherichia coli is regulated through multiple K(+) transport systems. Recent data indicate that not all K(+) extrusion system(s) have been identified (15). Here we report that the E. coli Na(+) (Ca(2+))/H(+) antiporter ChaA functions as a K(+) extrusion system. Cells expressing ChaA mediated K(+) efflux against a K(+) concentration gradient. E. coli strains lacking the chaA gene were unable to extrude K(+) under conditions in which wild-type cells… CONTINUE READING