The voltage-gated Na+ channel NaVBP has a role in motility, chemotaxis, and pH homeostasis of an alkaliphilic Bacillus.

ABSTRACT: The prokaryotic voltage-gated Na(+) channel, NaChBac, is one of a growing channel superfamily of unknown function. Here we show that Na(V)BP, the NaChBac homologue encoded by ncbA in alkaliphilic Bacillus pseudofirmus OF4, is a voltage-gated Na(+) channel potentiated by alkaline pH. Na(V)BP has roles in motility, chemotaxis, and pH homeostasis at high pH. Reduced motility of bacteria lacking functional Na(V)BP was reversed by restoration of the native channel but not by a mutant Na(V)BP engineered to be Ca(2+)-selective. Motile ncbA mutant cells and wild-type cells treated with a channel inhibitor exhibited behavior opposite to the wild type in response to chemoeffectors. Mutants lacking functional Na(V)BP were also defective in pH homeostasis in response to a sudden alkaline shift in exte

SUBMITTER: Ito M 

PROVIDER: S-EPMC490023 | biostudies-literature | 2004 Jul

REPOSITORIES: biostudies-literature