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The Na + ‐motive respiration in Escherichia coli
Author(s) -
Avetisyan A.V.,
Dibrov P.A.,
Skulachev V.P.,
Sokolov M.V.
Publication year - 1989
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(89)81000-2
Subject(s) - protonophore , monensin , chemistry , antiporter , cyanide , escherichia coli , antimycin a , oligomycin , incubation , medicinal chemistry , vesicle , membrane potential , nuclear chemistry , biochemistry , membrane , inorganic chemistry , atpase , electron transport chain , enzyme , gene
The protonophorous uncoupler carbonyl cyanide m ‐chlorophenylhydrazone was found to inhibit the growth rate of E. coli and maintenance of the membrane potential (Δψ) in intact bacterial cells. Both inhibitory effects of the protonophore were strongly decreased by Na + . A favourable action of Na + could be observed only when cells were grown under conditions of low Δµ̃H, i.e. at alkaline pH (8.6) or in the presence of the photonophore in growth medium. It was abolished by addition of ΔpH‐dissipating agents, i.e. the penetrating weak base diethylamine and the Na + /H + antiporter monensin, to the incubation medium. In inside‐out subcellular vesicles isolated from cells grown at alkaline pH, NADH oxidation was shown to be coupled to Na + uptake which was markedly stimulated by protonophore and inhibited by cyanide and HQNO. It is concluded that the growth of E. coli at alkaline pH or in the presence of protonophore gives rise to the induction of a primary respiratory Na + pump(s).