Analyses of a Bacillus subtilis homologue of the Na+/H+ antiporter gene which is important for pH homeostasis of alkaliphilic Bacillus sp. C-125.
Bacillus subtilis was revealed to have a homologous region to the DNA fragment responsible for alkaliphily of alkaliphilic Bacillus sp. C-125 on the genome, as reported previously [1]. The yufT gene on the B. subtilis genome showed a significant similarity with ORF1 of Bacillus sp. C-125, which is related to membrane potential (DeltaPsi)-driven Na+/H+ antiport activity and is important for pH homeostasis in an alkaline condition. Disruption of the yufT gene resulted in the decrease of Na+/H+ antiport activity, and the growth of the yufT disrupted strain was impaired with an increase in the external Na+ concentration. We conclude that the yufT gene encodes a Na+/H+ antiporter, which has a dominant role in the extrusion of cytotoxic Na+.
Kosono
S
S
Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. kosono@postman.riken.go.jp
Morotomi
S
S
Kitada
M
M
Kudo
T
T
D001412:Bacillus subtilis / Q000235:genetics* / Q000502:physiology; D006706:Homeostasis; D006863:Hydrogen-Ion Concentration; D005810:Multigene Family; D016296:Mutagenesis; D017923:Sodium-Hydrogen Exchangers / Q000235:genetics*
D017923:Sodium-Hydrogen Exchangers