title: A primary sodium pump gene of the moderate halophile Halobacillus dabanensis exhibits secondary antiporter properties.
abstract: The primary sodium pump has been proved to be involved in Na(+) extrusion of bacteria. In our present study, a novel gene encoding a putative primary sodium pump was cloned from chromosomal DNA of moderate halophile Halobacillus dabanensis D-8 by functional complementation, which expression resulted in the growth of antiporter-deficient Escherichia coli strain KNabc in the presence of 0.2 M NaCl. The gene was sequenced and designated nap. The deduced amino acid sequence of Nap has 56% identity to NADH dehydrogenase of Bacillus cereus and 55% to NADH oxidase of Bacillus halodurans C-125. E. coli KNabc carrying nap exhibited resistance to uncoupler CCCP (carbonyl-cyanide m-chlorophenylhydrazone). Everted membrane vesicles prepared from E. coli KNabc carrying nap exhibited secondary Na(+)/H(+) antiporter activity, and nap also supported the growth of respiratory-deficient E. coli ANN0222 lacking NADH dehydrogenase. Based on these results, we proposed that Nap possessed both characteristics of secondary Na(+)/H(+) antiporter and primary sodium pump.
authors.affiliation: Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Key Laboratory of Agro-Microbial Resource and Application of Ministry of Agriculture, Beijing.
authors.forename: Lifu
authors.initials: L
authors.lastname: Yang
authors.forename: Juquan
authors.initials: J
authors.lastname: Jiang
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Baisuo
authors.initials: B
authors.lastname: Zhao
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Su Sheng
authors.initials: SS
authors.lastname: Yang
mesh_terms: D000595:Amino Acid Sequence; D017920:Antiporters / Q000235:genetics / Q000502:physiology*; D001406:Bacillaceae / Q000201:enzymology*; D001407:Bacillus / Q000201:enzymology / Q000235:genetics; D001483:Base Sequence; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D002462:Cell Membrane / Q000201:enzymology; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000502:physiology; D009245:NADH Dehydrogenase / Q000502:physiology; D009247:NADH, NADPH Oxidoreductases / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000235:genetics / Q000502:physiology*; D014475:Uncoupling Agents / Q000494:pharmacology
chemical_list: D017920:Antiporters; D004269:DNA, Bacterial; D009097:Multienzyme Complexes; D014475:Uncoupling Agents; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D009245:NADH Dehydrogenase; D000254:Sodium-Potassium-Exchanging ATPase