A Central Role for Magnesium Homeostasis during Adaptation to Osmotic Stress.
A Central Role for Magnesium Homeostasis during Adaptation to Osmotic Stress.
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DOI：
10.1128/mbio.00092-22
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发表时间：
2022-02-22
期刊：
影响因子：
6.4
通讯作者：
Helmann JD
中科院分区：
文献类型：
--
作者：
Wendel BM;Pi H;Krüger L;Herzberg C;Stülke J;Helmann JD
渗透压是自由生活细胞的一个重要物理挑战。来自所有三个生命领域的细胞在渗透胁迫期间通过严格调节主要的细胞渗压剂钾（K+）和通过输入或合成相容性溶质来维持活力。已经广泛确定的是，响应于高盐胁迫，许多细菌瞬时积累高水平的K+，导致抑菌作用，只有当相容性溶质积累并且K+水平恢复到生物相容性水平时才恢复生长。使用枯草芽孢杆菌作为模型系统，我们提供的证据表明，K+通量扰动Mg 2+稳态：进口K+渗透上移后与Mg 2+外流，Mg 2+再进口是至关重要的适应。高渗胁迫引起的短暂生长抑制与Mg ~（2+）的丢失和蛋白质翻译的减少一致。相反，Mg 2+的再输入是恢复生长期间的限制因素。此外，我们表明，必要的信号二核苷酸环二AMP动态波动与Mg 2+和K+水平的协调，一致的建议，环二AMP编排细胞对渗透胁迫的反应。
Osmotic stress is a significant physical challenge for free-living cells. Cells from all three domains of life maintain viability during osmotic stress by tightly regulating the major cellular osmolyte potassium (K+) and by import or synthesis of compatible solutes. It has been widely established that in response to high salt stress, many bacteria transiently accumulate high levels of K+, leading to bacteriostasis, with growth resuming only when compatible solutes accumulate and K+ levels are restored to biocompatible levels. Using Bacillus subtilis as a model system, we provide evidence that K+ fluxes perturb Mg2+ homeostasis: import of K+ upon osmotic upshift is correlated with Mg2+ efflux, and Mg2+ reimport is critical for adaptation. The transient growth inhibition resulting from hyperosmotic stress is coincident with loss of Mg2+ and a decrease in protein translation. Conversely, the reimport of Mg2+ is a limiting factor during resumption of growth. Furthermore, we show the essential signaling dinucleotide cyclic di-AMP fluctuates dynamically in coordination with Mg2+ and K+ levels, consistent with the proposal that cyclic di-AMP orchestrates the cellular response to osmotic stress.