Cell-wall remodeling drives engulfment during Bacillus subtilis sporulation.
Cell-wall remodeling drives engulfment during Bacillus subtilis sporulation.
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DOI：
10.7554/elife.18657
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发表时间：
2016-11-17
期刊：
影响因子：
7.7
通讯作者：
Endres, Robert G
中科院分区：
文献类型：
--
作者：
Ojkic, Nikola;Lopez-Garrido, Javier;Endres, Robert G
当处于饥饿状态时，革兰氏阳性细菌枯草芽孢杆菌会形成耐用的芽孢以存活。芽孢形成始于不对称细胞分裂，产生一个大的母细胞和一个小的前芽孢。随后，母细胞膜在一个类似吞噬作用的过程中吞没前芽孢。然而，推动膜向前移动的力产生机制仍然未知。在此，我们表明膜迁移是由吞没膜前沿的细胞壁重塑驱动的，肽聚糖的合成与降解由前芽孢中的青霉素结合蛋白以及母细胞中的一个细胞壁降解蛋白复合物介导。我们提出一个简单的吞没模型，其中隔膜和侧壁细胞壁之间的连接通过一种类似于“模板模型”的机制围绕前芽孢移动。因此，我们基于细胞壁合成与降解之间的协同作用，确立了一种产生吞没力的生物物理机制。
When starved, the Gram-positive bacterium Bacillus subtilis forms durable spores for survival. Sporulation initiates with an asymmetric cell division, creating a large mother cell and a small forespore. Subsequently, the mother cell membrane engulfs the forespore in a phagocytosis-like process. However, the force generation mechanism for forward membrane movement remains unknown. Here, we show that membrane migration is driven by cell wall remodeling at the leading edge of the engulfing membrane, with peptidoglycan synthesis and degradation mediated by penicillin binding proteins in the forespore and a cell wall degradation protein complex in the mother cell. We propose a simple model for engulfment in which the junction between the septum and the lateral cell wall moves around the forespore by a mechanism resembling the 'template model'. Hence, we establish a biophysical mechanism for the creation of a force for engulfment based on the coordination between cell wall synthesis and degradation.