Ionic selectivity and thermal adaptations within the voltage-gated sodium channel family of alkaliphilic Bacillus

Paul G. DeCaen, Yuka Takahashi, Terry A. Krulwich, Masahiro Ito, David E. Clapham*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

24 Scopus citations

Abstract

Entry and extrusion of cations are essential processes in living cells. In alkaliphilic prokaryotes, high external pH activates voltage-gated sodium channels (Nav), which allows Na+ to enter and be used as substrate for cation/proton antiporters responsible for cytoplasmic pH homeostasis. Here, we describe a new member of the prokaryotic voltage-gated Na+ channel family (NsvBa; Non-selective voltage-gated, Bacillus alcalophilus) that is nonselective among Na+, Ca2+ and K+ ions. Mutations in NsvBa can convert the nonselective filter into one that discriminates for Na+ or divalent cations. Gain-of-function experiments demonstrate the portability of ion selectivity with filter mutations to other Bacillus Nav channels. Increasing pH and temperature shifts their activation threshold towards their native resting membrane potential. Furthermore, we find drugs that target Bacillus Nav channels also block the growth of the bacteria. This work identifies some of the adaptations to achieve ion discrimination and gating in Bacillus Nav channels.

Original languageEnglish (US)
Article numbere04387
Pages (from-to)1-15
Number of pages15
JournaleLife
Volume3
Issue numberNovember
DOIs
StatePublished - Nov 11 2014

ASJC Scopus subject areas

  • Neuroscience(all)
  • Immunology and Microbiology(all)
  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'Ionic selectivity and thermal adaptations within the voltage-gated sodium channel family of alkaliphilic Bacillus'. Together they form a unique fingerprint.

Cite this