Lamrabet Otmane, Munoz-Ruiz Raphael, Ayadi Imen, Bourbon Alixia, Pain Erwann, Oddy Joseph, Cosson Pierre
Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Department of Applied Biology, College of Sciences, University of Sharjah, University City, Sharjah, UAE.
Mol Microbiol. 2025 Jul;124(1):54-65. doi: 10.1111/mmi.15367. Epub 2025 May 4.
Phagocytic cells ingest bacteria and kill them in phagosomes. A variety of molecular mechanisms allow the killing and destruction of bacteria in phagosomes, but their complete list and relative importance remain poorly defined. Here we have used Dictyostelium discoideum amoebae as model phagocytic cells. Our results reveal that PldX, a luminal phospholipase D, plays an important role in the phagosomal destruction of ingested bacteria. Analysis of bacterial destruction in wild-type and pldX KO living cells suggests that PldX participates in the permeabilization of the bacterial membrane. The bacteriolytic activity of D. discoideum extracts was also measured in vitro: extracts from pldX KO cells exhibit significantly less bacteriolytic activity than wild-type cells, confirming the role of PldX in the lysis of bacterial membranes. These results identify luminal phospholipase D as a major player in the permeabilization of bacterial membranes in phagosomes.
吞噬细胞摄取细菌并在吞噬体中将其杀死。多种分子机制可实现吞噬体内细菌的杀灭和破坏，但其完整清单及相对重要性仍不清楚。在这里，我们使用盘基网柄菌变形虫作为模型吞噬细胞。我们的结果表明，腔内磷脂酶D（PldX）在吞噬体中摄取细菌的破坏过程中起重要作用。对野生型和pldX基因敲除活细胞中细菌破坏情况的分析表明，PldX参与细菌膜的通透化过程。还在体外测量了盘基网柄菌提取物的溶菌活性：pldX基因敲除细胞的提取物显示出比野生型细胞明显更低的溶菌活性，证实了PldX在细菌膜裂解中的作用。这些结果确定腔内磷脂酶D是吞噬体中细菌膜通透化的主要参与者。
