title: Growth of a marine Vibrio alginolyticus and moderately halophilic V. costicola becomes uncoupler resistant when the respiration-dependent Na+ pump functions.
abstract: The growth of Vibrio alginolyticus and V. costicola, which possess respiration-dependent Na+ pumps, was highly resistant to the proton conductor carbonyl cyanide-m-chlorophenyl hydrazone (CCCP), in alkaline growth media, even though the membrane was rendered permeable to H+. The pH dependence of CCCP-resistant growth was similar to that of the Na+ pump. In contrast, Escherichia coli ML308-225 showed neither Na+ pump activity nor CCCP-resistant growth, even when grown in alkaline, Na+-rich media. These results suggest that certain bacteria possess the Na+ pump and are thus able to grow under the conditions where H+ circulation across the membrane does not take place. Moreover, V. alginolyticus growing in the presence of CCCP maintains normal levels of internal K+, Na+, and H+. The Na+ pump, therefore, makes the growth of these organisms resistant to CCCP by maintaining the intracellular cation environments.
mesh_terms: D001693:Biological Transport, Active / Q000187:drug effects; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D007473:Ion Channels / Q000378:metabolism*; D007700:Kinetics; D009154:Mutation; D009570:Nitriles / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects*; D012623:Seawater; D012964:Sodium / Q000378:metabolism*; D013696:Temperature; D014733:Vibrio / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*
chemical_list: D007473:Ion Channels; D009570:Nitriles; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D012964:Sodium