K+ influx by Kup in Escherichia coli is accompanied by a decrease in H+ efflux.

E Zakharyan; A Trchounian

doi:10.1111/j.1574-6968.2001.tb10863.x

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K+ influx by Kup in Escherichia coli is accompanied by a decrease in H+ efflux.

E Zakharyan·A Trchounian

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Abstract

Escherichia coli accumulates K+ by means of multiple uptake systems of which Kup is the major transport system at acidic pH. In cells grown under fermentative conditions at pH 5.5, K+ influx by a wild-type strain upon hyper-osmotic stress at pH 5.5 was accompanied by a marked decrease in H+ efflux, with a 1:1 ratio of K+ to H+ fluxes. This was observed with cells treated with N,N'-dicyclohexylcarbodiimide. Similar results with a mutant defective in Kdp and TrkA but with a functional Kup system but not in a mutant defective in Kdp and Kup but having an active TrkA system suggest that Kup operates as a H+ -K+ -symporter.

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Adenosine Triphosphatases Carrier Proteins Escherichia coli Hydrogen Hydrogen-Ion Concentration Ion Transport Membrane Proteins Osmotic Pressure Potassium Proton-Motive Force Journal Article Research Support, Non-U.S. Gov't

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E Zakharyan, A Trchounian. 2001-10-16. K+ influx by Kup in Escherichia coli is accompanied by a decrease in H+ efflux.. https://doi.org/10.1111/j.1574-6968.2001.tb10863.x

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