Referenced in: none

Automatically associated channels: Kv2.1

Title: Motility and chemotaxis in alkaliphilic Bacillus species.

Authors: Shun Fujinami, Naoya Terahara, Terry Ann Krulwich, Masahiro Ito

Journal, date & volume: Future Microbiol, 2009 Nov , 4, 1137-49

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/19895217

Abstract
Alkaliphilic Bacillus species grow at pH values up to approximately 11. Motile alkaliphilic Bacillus use electrochemical gradients of Na(+) (sodium-motive force) to power ion-coupled, flagella-mediated motility as opposed to the electrochemical gradients of H(+) (proton-motive force) used by most neutralophilic bacteria. Membrane-embedded stators of bacterial flagella contain ion channels through which either H(+) or Na(+) flow to energize flagellar rotation. Stators of the major H(+)-coupled type, MotAB, are distinguishable from Na(+)-coupled stators, PomAB of marine bacteria and MotPS of alkaliphilic Bacillus. Dual ion-coupling capacity is found in neutralophilic Bacillus strains with both MotAB and MotPS. There is also a MotAB variant that uses both coupling ions, switching as a function of pH. Chemotaxis of alkaliphilic Bacillus depends upon flagellar motility but also requires a distinct voltage-gated NaChBac-type channel. The two alkaliphile Na(+) channels provide new vistas on the diverse adaptations of sensory responses in bacteria.