Respiration-dependent primary Na+ pump in halophilic marine bacterium, Alcaligenes strain 201

AbstractThe inverted membrane vesicles of marine bacterium Alcaligenes strain 201 generated inside positive membrane potential and accumulated Na+ on the energization with NADH. Both the generation of membrane potential and the accumulation of Na+ were resistant to a proton conductor, carbonyl cyanide m-chlorophenylhydrazone. Collapse of the membrane potential by valinomycin resulted in the stimulation of Na+ accumulation. It was concluded that Alcaligenes strain 201 possesses a respiratory Na+ pump which is analogous to that of Vibrio alginolyticus.Inverted vesicle; Na+ pump; Marine bacteria; Respiratory chai