Submicromolar Ag+ increases passive Na+ permeability and inhibits the respiration-supported formation of Na+ gradient in Bacillus FTU vesicles.
In: FEBS letters, Jg. 269 (1990-08-20), Heft 1, S. 69-72
academicJournal
Zugriff:
The effect of Ag+ on Na+ pumping by Na(+)-motive NADH-quinone reductase and terminal oxidase has been studied in Bacillus FTU inside-out vesicles. Very low concentrations of Ag+ (C1/2 = 1 x 10(-8) M or 2 x 10(-12) g ion.mg protein-1) are shown to inhibit the uphill Na+ uptake coupled to the oxidation of NADH by fumarate or of ascorbate + TMPD by oxygen but exert no effect on the H+ uptake by the H(+)-motive respiratory chain. Low Ag+ also induces a specific increase in the Na+ permeability of the vesicles. HQNO, added before and not after Ag+, prevents the Ag(+)-induced permeability increase, with effective HQNO concentrations being similar to those inhibiting the uphill Na(+)-uptake coupled to the NADH-fumarate oxidoreduction. Reduction of terminal oxidase by ascorbate + TMPD in the presence of cyanide sensitizes the Na+ permeability to Ag+. It is suggested that low [Ag+], known as a specific inhibitor of electron transport by the Na(+)-motive NADH-quinone reductase, uncouples the electron and Na+ transports so that the Ag(+)-modified NADH-quinone reductase operates as an Na+ channel rather than an Na+ pump. This effect is discussed in connection with the antibacterial action of Ag+.
Titel: |
Submicromolar Ag+ increases passive Na+ permeability and inhibits the respiration-supported formation of Na+ gradient in Bacillus FTU vesicles.
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Autor/in / Beteiligte Person: | Semeykina, AL ; Skulachev, VP |
Zeitschrift: | FEBS letters, Jg. 269 (1990-08-20), Heft 1, S. 69-72 |
Veröffentlichung: | Jan. 2016- : West Sussex : John Wiley & Sons Ltd. ; <i>Original Publication</i>: Amsterdam, North-Holland on behalf of the Federation of European Biochemical Societies., 1990 |
Medientyp: | academicJournal |
ISSN: | 0014-5793 (print) |
DOI: | 10.1016/0014-5793(90)81120-d |
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