Department of Crystallography and Structural Biology, Instituto de Química-Física "Rocasolano," Consejo Superior de Investigaciones Científicas, Madrid, Spain.
Molecular Microbiology and Structural Biochemistry, UMR 5086, Université de Lyon, CNRS, Lyon, France.
Cell Rep. 2023 Jul 25;42(7):112756. doi: 10.1016/j.celrep.2023.112756. Epub 2023 Jul 6.
Bacterial cell-wall hydrolases must be tightly regulated during bacterial cell division to prevent aberrant cell lysis and to allow final separation of viable daughter cells. In a multidisciplinary work, we disclose the molecular dialogue between the cell-wall hydrolase LytB, wall teichoic acids, and the eukaryotic-like protein kinase StkP in Streptococcus pneumoniae. After characterizing the peptidoglycan recognition mode by the catalytic domain of LytB, we further demonstrate that LytB possesses a modular organization allowing the specific binding to wall teichoic acids and to the protein kinase StkP. Structural and cellular studies notably reveal that the temporal and spatial localization of LytB is governed by the interaction between specific modules of LytB and the final PASTA domain of StkP. Our data collectively provide a comprehensive understanding of how LytB performs final separation of daughter cells and highlights the regulatory role of eukaryotic-like kinases on lytic machineries in the last step of cell division in streptococci.
在细菌细胞分裂过程中，细菌细胞壁水解酶必须受到严格的调控，以防止异常的细胞裂解，并允许有活力的子细胞最终分离。在一项多学科的工作中，我们揭示了肺炎链球菌细胞壁水解酶 LytB、细胞壁磷壁酸和类真核蛋白激酶 StkP 之间的分子对话。在对 LytB 的催化结构域的肽聚糖识别模式进行了表征之后，我们进一步证明 LytB 具有模块化组织，允许其特异性结合细胞壁磷壁酸和蛋白激酶 StkP。结构和细胞研究特别揭示了 LytB 的时空定位受 LytB 的特定模块与 StkP 的最终 PASTA 结构域之间的相互作用控制。我们的数据综合提供了一个全面的了解，即 LytB 如何执行子细胞的最终分离，并强调了类真核蛋白激酶在链球菌细胞分裂最后一步中裂解机制上的调控作用。
