The Ktr potassium transport system in Staphylococcus aureus and its role in cell physiology, antimicrobial resistance and pathogenesis.
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ABSTRACT:
SUBMITTER: Gries CM
PROVIDER: S-EPMC3754831 | biostudies-literature | 2013 Aug
REPOSITORIES: biostudies-literature
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The Ktr potassium transport system in Staphylococcus aureus and its role in cell physiology, antimicrobial resistance and pathogenesis.
Gries Casey M CM Bose Jeffrey L JL Nuxoll Austin S AS Fey Paul D PD Bayles Kenneth W KW
Molecular microbiology 20130717 4
Potassium (K(+) ) plays a vital role in bacterial physiology, including regulation of cytoplasmic pH, turgor pressure and transmembrane electrical potential. Here, we examine the Staphylococcus aureus Ktr system uniquely comprised of two ion-conducting proteins (KtrB and KtrD) and only one regulator (KtrA). Growth of Ktr system mutants was severely inhibited under K(+) limitation, yet detectable after an extended lag phase, indicating the presence of a secondary K(+) transporter. Disruption of b ...[more]
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