Iwańska Olga, Latoch Przemysław, Kovalenko Mariia, Lichocka Małgorzata, Hołówka Joanna, Serwa Remigiusz, Grzybowska Agata, Zakrzewska-Czerwińska Jolanta, Starosta Agata L
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
Department of Molecular Microbiology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland.
Nat Commun. 2025 Jan 3;16(1):354. doi: 10.1038/s41467-024-55196-9.
In the spore-forming bacterium Bacillus subtilis transcription and translation are uncoupled and the translational machinery is located at the cell poles. During sporulation, the cell undergoes morphological changes including asymmetric division and chromosome translocation into the forespore. However, the fate of translational machinery during sporulation has not been described. Here, using microscopy and mass spectrometry, we show the localisation of ribosomes during sporulation in wild type and mutant Bacillus subtilis. We demonstrate that ribosomes are associated with the asymmetric septum, a functionally important organelle in the cell's developmental control, and that SpoIIDMP-driven peptidoglycan rearrangement is crucial for ribosomes packing into the forespore. We also show that the SpoIIIA-SpoIIQ 'feeding-tube' channel is not required for ribosome translocation. Our results demonstrate that translation and translational machinery are temporally and spatially organised in B. subtilis during sporulation and that the forespore 'inherits' ribosomes from the mother cell. We propose that the movement of ribosomes in the cell may be mediated by the bacterial homologs of cytoskeletal proteins and that the cues for asymmetric division localisation may be translation-dependent. We anticipate our findings to elicit more sophisticated structural and mechanistic studies of ribosome organisation during bacterial cell development.
在形成芽孢的细菌枯草芽孢杆菌中，转录和翻译是解偶联的，翻译机制位于细胞两极。在芽孢形成过程中，细胞会经历形态变化，包括不对称分裂和染色体向芽孢的转位。然而，芽孢形成过程中翻译机制的命运尚未得到描述。在这里，我们使用显微镜和质谱技术，展示了野生型和突变型枯草芽孢杆菌在芽孢形成过程中核糖体的定位。我们证明核糖体与不对称隔膜相关，不对称隔膜是细胞发育控制中一个功能重要的细胞器，并且SpoIIDMP驱动的肽聚糖重排对于核糖体包装到芽孢中至关重要。我们还表明，SpoIIIA - SpoIIQ“进料管”通道对于核糖体转位不是必需的。我们的结果表明，在枯草芽孢杆菌芽孢形成过程中，翻译和翻译机制在时间和空间上是有组织的，并且芽孢从母细胞“继承”了核糖体。我们提出细胞中核糖体的移动可能由细胞骨架蛋白的细菌同源物介导，并且不对称分裂定位的线索可能是翻译依赖性的。我们预计我们的发现将引发对细菌细胞发育过程中核糖体组织更复杂的结构和机制研究。
