Light‐dependent Δ̄smNa‐generation and utilization in the marine cyanobacterium Oscillatoria brevis

FEBS Letters

Brown, I.I.¹  Fadeyev, S.I.¹  Kirik, I.I.¹  Severina, I.I.²  Skulachev, V.P.² 

[1] Department of Biology, Odessa State University, Odessa 270057, USSR;A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, Moscow State University, Moscow 119899, USSR

关键词: Na+ energetics;    Cyanobacteria;    Oscillatoria brevis;    Δ̄smH and Δ̄smNa;    transmembrane electrochemical H+ and Na+ potential differences;    respectively;    Δψ transmembrane electric potential difference;    ΔpH and ΔpNa;    transmembrane H+ and Na+ concentration differences;    respectively;    CCCP;    carbonyl cyanide-m-chlorophenyl hydrazone;    [Na+]in;    intracellular Na+ concentration;    TPP+ tetraphenylphosphonium;   

DOI  :  10.1016/0014-5793(90)81268-S

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Light-dependent Na⁺ and H⁺ transports, membrane potential (Δψ) and motility have been studied in the cells of the marine cyanobacterium Oscillatoria brevis. In the presence of a protonophorous uncoupler, carbonyl cyanide-m-chlorophenylhydrazone, the intracellular Na⁺ level is shown to increase in the dark and decrease in the light. The Na⁺/H⁺ antiporter, monensin, stimulates the dark CCCP-dependent [Na⁺]_in increase and abolishes the light-dependent [Na⁺]_in decrease. Na⁺ ions are necessary for the fast light-induced Δψ generation and H⁺ uptake by the cells. This uptake is inhibited by monensin being resistant to CCCP. Monensin sensitizes the Δψ level and the motility rate to low CCCP concentrations. The obtained data are consistent with the assumption that O. brevis possesses a primary Na⁺ pump which utilizes (directly or indirectly) the light energy.

【 授权许可】

Unknown