Growth Inhibition by External Potassium of Escherichia coli Lacking PtsN (EIIANtr) Is Caused by Potassium Limitation Mediated by YcgO.

ABSTRACT:

Unlabelled

The absence of PtsN, the terminal phosphoacceptor of the phosphotransferase system comprising PtsP-PtsO-PtsN, in Escherichia coli confers a potassium-sensitive (K(s)) phenotype as the external K(+) concentration ([K(+)]e) is increased above 5 mM. A growth-inhibitory increase in intracellular K(+) content, resulting from hyperactivated Trk-mediated K(+) uptake, is thought to cause this K(s) We provide evidence that the K(s) of the ΔptsN mutant is associated with K(+) limitation. Accordingly, the moderate K(s) displayed by the ΔptsN mutant was exacerbated in the absence of the Trk and Kup K(+) uptake transporters and was associated with reduced cellular K(+) content. Conversely, overproduction of multiple K(+) uptake proteins suppressed the K(s) Expression of PtsN variants

SUBMITTER: Sharma R 

PROVIDER: S-EPMC4907114 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature