Gow J A, MacLeod R A
Can J Microbiol. 1981 Mar;27(3):358-63. doi: 10.1139/m81-054.
Cells of a histidine-auxotrophic, streptomycin-resistant mutant of marine bacterium Alteromonas haloplanktis 214 were grown at or near the lowest concentration of Na+ permitting growth (30-33 mM Na+). When suspended in solutions containing 10 mMKCl and either 30, 100, or 300 mM NaCl, the intracellular to extracellular K+ ratios were similar to those obtained with cells of the parent organism grown at more nearly optimum Na+ concentrations, whereas the Na+ ratios were somewhat larger. Cells of the parent organism grown at 32 mM Na+ transported alpha-aminoisobutyric acid (AIB) at only one-third the rate and to less than one-quarter of the extent of cells grown at 130 mM Na+ even when the NaCl concentration during transport was raised to optimum levels. The Km for uptake of AIB by cells grown at 32 and 130 mM Na+ was the same but the Vmax was higher for cells grown at 130 mM. The Vmax for cells grown at both concentrations of Na+ increased as the Na+ concentration in the uptake medium increased. It was concluded that none of the observations made could account for the fact that both parent and mutant of A. haloplanktis grow at 30-32 mM Na+ only after a very long lag period, and then grow at near normal rates once logarithmic growth begins despite the fact that the osmotic pressure of the medium is very low.
海洋细菌嗜盐浮游交替单胞菌214的组氨酸营养缺陷型、链霉素抗性突变体的细胞，在允许生长的最低Na⁺浓度（30 - 33 mM Na⁺）或接近该浓度的条件下培养。当悬浮于含有10 mM KCl以及30、100或300 mM NaCl的溶液中时，细胞内与细胞外的K⁺比率与在更接近最佳Na⁺浓度下生长的亲代生物体的细胞所获得的比率相似，而Na⁺比率则略高。在32 mM Na⁺条件下生长的亲代生物体的细胞，即使在运输过程中将NaCl浓度提高到最佳水平，其转运α-氨基异丁酸（AIB）的速率也仅为在130 mM Na⁺条件下生长的细胞的三分之一，转运程度不到其四分之一。在32 mM和130 mM Na⁺条件下生长的细胞摄取AIB的Km相同，但130 mM条件下生长的细胞的Vmax更高。在两种Na⁺浓度条件下生长的细胞的Vmax均随着摄取培养基中Na⁺浓度的增加而增加。得出的结论是，所做的任何观察都无法解释嗜盐浮游交替单胞菌的亲代和突变体仅在非常长的延迟期后才在30 - 32 mM Na⁺条件下生长，然后一旦对数生长开始就以接近正常的速率生长这一事实，尽管培养基的渗透压非常低。
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