Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, the Netherlands.
Environ Microbiol. 2013 Dec;15(12):3272-81. doi: 10.1111/1462-2920.12206. Epub 2013 Jul 30.
The shape of bacteria is maintained by the cell wall. The main component of the cell wall is peptidoglycan (PG) that is synthesized by penicillin binding proteins (PBPs). The correct positioning of PBPs is essential for the maintenance of cell shape. In the literature, two different models for localization of PBPs have been proposed - localization through interaction with a cytoskeletal structure or localization through the presence of substrate. Here, we show that the localization of PBPs critical for the rod shape of Bacillus subtilis is altered when the substrate LipidII is delocalized by treatment of the cells with nisin. Alteration of this localization is only seen in a LipidII-dependent manner and is not influenced by dissipation of the membrane potential, a secondary effect of nisin treatment. Our results strongly suggest that the localization of PG synthesis at the periphery of the cell is substrate-driven, even in bacteria that contain actin-like MreB cytoskeletal structures.
细菌的形状由细胞壁维持。细胞壁的主要成分是肽聚糖（PG），它由青霉素结合蛋白（PBP）合成。PBP 的正确定位对于维持细胞形状至关重要。在文献中，已经提出了两种不同的 PBP 定位模型 - 通过与细胞骨架结构相互作用的定位或通过存在底物的定位。在这里，我们表明，当用乳链菌肽处理细胞导致脂质 II 去定位时，对枯草芽孢杆菌杆状形状至关重要的 PBP 的定位会发生改变。这种定位的改变仅以脂质 II 依赖性的方式出现，并且不受乳链菌肽处理的膜电位耗散的影响，这是乳链菌肽处理的次要影响。我们的结果强烈表明，即使在含有肌动蛋白样 MreB 细胞骨架结构的细菌中，细胞周围 PG 合成的定位也是底物驱动的。
