Bacterial Na+ energetics

FEBS Letters

Skulachev, Vladimir P.¹ 

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

关键词: Na+ energetics;    ATPase;    Terminal oxidase;    Methanogen;    Decarboxylase;    Δµ̃H and Δµ̃Na;    electrochemical potential differences of H+ and Na+;    respectively;    ΔpH and ΔpNa;    concentration differences of H+ and Na+;    Δψ;    electric potential difference;    DCCD;    N;    N′-dicyclohexylcarbodiimide;   

DOI  :  10.1016/0014-5793(89)80693-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Novel observations related to the Na⁺-linked energy transduction in bacterial membranes are considered. It is concluded that, besides the well-known systems based on the circulation of protons, there are those based on the circulation of Na⁺. In some cases, H⁺ and Na⁺ cycles co-exist in one and the same membrane. Representatives of the ‘sodium world’, i.e. cells possessing primary Na⁺ pumps (ΔΔµ̃Na generators and consumers) are found in many genera of bacteria. Among the ΔΔµ̃Na generators, one should mention Na⁺-NADH-quinone reductase and Na⁺-terminal oxidase of the respiratory chain, Na⁺-decarboxylases and Na⁺-ATPases. For Δµ̃Na consumers, there are Na⁺-ATP-synthases, Na⁺-metabolite symporters and Na⁺ motors. Sometimes, one and the same enzyme can transport H⁺ or, alternatively, Na⁺. For instance, an Na⁺-ATP-synthase of the F₀F₁ type translocates H⁺ when Na⁺ is absent. Employment of the Na⁺ cycle, apart from or instead of the H⁺ cycle, increases the resistance of bacteria to alkaline or protonophore-containing media and, apparently, to some other unfavourable conditions.

【 授权许可】

Unknown