Institute of Molecular Biology, University Hospital Essen, University Duisburg-Essen, 45259 Essen, Germany.
Department of Thoracic and Cardiovascular Surgery, Thoracic Transplantation, University Hospital Essen, University Duisburg-Essen, West German Heart and Vascular Center, 45259 Essen, Germany.
Pathog Dis. 2024 Feb 7;82. doi: 10.1093/femspd/ftae016.
Sphingosine has been previously shown to kill many strains of pathogenic bacteria including Pseudomonas aeruginosa, Staphyloccus aureus, Acinetobacter, and atypical mycobacteria. However, these studies were performed on isolated or extracellular bacteria and it is unknown whether sphingosine also targets intracellular bacteria. Here, we demonstrate that exogenously-added sphingosine directly binds to extracellular P. aeruginosa and S. aureus, but also targets and binds to intracellular bacteria. Intracellular sphingosine and bacteria were identified by sequential immunostainings. We further show that exogenously-added sphingosine also kills intracellular P. aeruginosa and S. aureus using modified gentamycin assays. Intracellular killing of P. aeruginosa and S. aureus by sphingosine is not mediated by improved phagosomal-lysosomal fusion. In summary, our data indicate that sphingosine binds to and most likely also directly kills extra- and intracellular P. aeruginosa and S. aureus.
鞘氨醇先前已被证明可杀死包括绿脓假单胞菌、金黄色葡萄球菌、不动杆菌和非典型分枝杆菌在内的多种致病菌。然而，这些研究是在分离或细胞外细菌上进行的，尚不清楚鞘氨醇是否也针对细胞内细菌。在这里，我们证明了外源性添加的鞘氨醇直接与细胞外的绿脓假单胞菌和金黄色葡萄球菌结合，但也针对并结合了细胞内细菌。通过连续免疫染色鉴定细胞内的鞘氨醇和细菌。我们还进一步表明，使用改良的庆大霉素测定法，外源性添加的鞘氨醇也可杀死细胞内的绿脓假单胞菌和金黄色葡萄球菌。鞘氨醇对绿脓假单胞菌和金黄色葡萄球菌的细胞内杀伤不是通过改善吞噬溶酶体融合介导的。总之，我们的数据表明鞘氨醇与外源性和细胞内的绿脓假单胞菌和金黄色葡萄球菌结合，并可能直接杀死它们。
