Unemoto T, Hayashi M, Hayashi M
J Biochem. 1977 Nov;82(5):1389-95. doi: 10.1093/oxfordjournals.jbchem.a131826.
Membrane-bound NADH oxidase activities from slightly halophilic marine Vibrio alginolyticus and moderately halophilic V. costicolus required 0.3 and 0.5 M Na+, respectively, for maximum activity; other cations such as Li+,K+,Rb+,Cs+,Mg2+, and Ca2+ were relatively ineffective as replacements for Na+. The concentration of Na+ required to give half-maximum activity with the NADH oxidase from V. alginolyticus was 82 mN. This value was reduced to 6.4 and 13.8 mM in the presence of 400 mM K+ and 10 mM Mg2+, respectively, indicating that K+ and Mg2+ cooperated with Na+ for activation. The same pattern of cation dependence was observed with the NADH oxidase from V. costicolus. The NADH oxidase from nonhalophilic Escherichia coli, however, had no specific requirement for Na+. Thus, Na+-dependent activation of NADH oxidase appeared to be a characteristic feature of these halophilic bacteria. All NADH oxidases examined were influenced by the species of anion present and the order of activating effect followed the lyotropic series:SO4(2-), CH3COO- greater than Cl- greater than NO3- greater than SCN-. Chaotropic anions such as NO3- and SCN- were inhibitory to the NADH oxidases, irrespective of the halophilic nature of the bacterial source.
来自轻度嗜盐海洋溶藻弧菌和中度嗜盐肋生弧菌的膜结合NADH氧化酶活性，分别需要0.3 M和0.5 M的Na⁺才能达到最大活性；其他阳离子如Li⁺、K⁺、Rb⁺、Cs⁺、Mg²⁺和Ca²⁺作为Na⁺的替代物相对无效。溶藻弧菌的NADH氧化酶产生半最大活性所需的Na⁺浓度为82 mM。在400 mM K⁺和10 mM Mg²⁺存在的情况下，该值分别降至6.4 mM和13.8 mM，表明K⁺和Mg²⁺与Na⁺协同激活。肋生弧菌的NADH氧化酶也观察到相同的阳离子依赖性模式。然而，来自非嗜盐大肠杆菌的NADH氧化酶对Na⁺没有特殊要求。因此，NADH氧化酶的Na⁺依赖性激活似乎是这些嗜盐细菌的一个特征。所有检测的NADH氧化酶都受存在的阴离子种类影响，激活作用顺序遵循感胶离子序：SO₄²⁻、CH₃COO⁻＞Cl⁻＞NO₃⁻＞SCN⁻。离液序列高的阴离子如NO₃⁻和SCN⁻对NADH氧化酶有抑制作用，无论细菌来源的嗜盐性质如何。
