摘要
Development of specific probes to study the in vivo spatial distribution of microorganisms is essential to understand the ecology of human microbiota. Herein, we assess the possibility of using liposomes loaded with fluorescently labeled nucleic acid mimics (LipoNAMs) to image Gram-negative and Gram-positive bacteria. We proved that liposome fusion efficiencies were similar in both Gram-negative and Gram-positive bacteria but that the efficiency was highly dependent on the lipid concentration. Notably, LipoNAMs were significantly more effective for the internalization of oligonucleotides in bacteria than the fixation/permeabilization methods commonly used in vitro. Furthermore, a structural and morphological assessment of the changes on bacteria allowed us to observe that liposomes increased the permeability of the cell envelope especially in Gram-negative bacteria. Considering the delivery efficiency and permeabilization effect, lipid concentrations of approximately 5 mM should be selected to maximize the detection of bacteria without compromising the bacterial cellular structure.
摘要译文
开发研究微生物体内空间分布的特定探针对于了解人类微生物群的生态至关重要。在本文中，我们评估了使用脂质体加载的脂质体的可能性。我们证明了脂质体融合效率在革兰氏阴性菌和革兰氏阳性细菌中都是相似的，但是效率高度依赖于脂质浓度。值得注意的是，与在体外常用的固定/透化方法相比，Liponam对细菌中寡核苷酸的内在化的有效性更高。此外，对细菌变化的结构和形态评估使我们观察到脂质体增加了细胞膜的渗透性，尤其是在革兰氏阴性菌中。考虑到递送效率和透化效应，应选择约5 mM的脂质浓度以最大程度地检测细菌，而不会损害细菌细胞结构。
Luís Moreira[1];Nuno M. Guimarães[1];Sara Pereira[1];Rita S. Santos[1];Joana A. Loureiro[1];Maria C. Pereira[1];Nuno F. Azevedo[1]. Liposome Delivery of Nucleic Acids in Bacteria: Toward In Vivo Labeling of Human Microbiota[J]. ACS Infectious Diseases, 2022,8(7): 1218-1230