哺乳动物细胞和组织中复制能力环状DNA分子的发现与使人衰弱的疾病有关,如多发性硬化症(MS),牛海绵状脑病(BSE),结直肠癌(CRC)。这些环状DNA分子,也被称为牛肉和牛奶因子(BMMF)和缓慢进展的可变(X)潜伏期(SPHINX)隐藏感染,与鲍曼不动杆菌菌株的质粒具有显著(80%)的序列相似性。纳米结构,例如细菌外膜囊泡(OMV)用作运输生物分子货物的载体,并且具有促进DNA的王国间横向迀移的潜力。加强提出的假设,这项研究表明,来自鲍曼不动杆菌DS002的OMV携带四个质粒和噬菌体基因组(pTS236),AbDs1,成功到达身体的不同部位,包括中枢神经系统,在将异硫氰酸荧光素(FITC)标记的OMV注射到实验小鼠中之后。在四个OMV相关质粒中,三个(pTS4586,pTS9900和pTS134338)在管腔内被识别,在OMV表面发现了第四个(pTS11291)。除了土著质粒,噬菌体编码的蛋白质,Orf96,通过与OMV相关的孔蛋白建立强烈的相互作用,锚定在OMV的表面上,OmpA.有趣的是,标记OMV的子集,当与Neuro2A细胞孵育时,跨膜转运并到达细胞的细胞质空间。总的来说,本文提供的实验证据强调了OMV作为将含有质粒和噬菌体基因组的分子货物递送至不同哺乳动物组织和细胞的载体的有希望的潜力。
目的:一些独立的研究已经证明在哺乳动物细胞和组织中存在细菌和病毒来源的具有复制能力的环状DNA分子。然而,关于它们的起源和向哺乳动物细胞的横向移动性的研究很少。我们的工作描述了环状DNA的存在,类似于哺乳动物细胞中鉴定的DNA分子,来自鲍曼不动杆菌DS002的土壤分离物的OMV。此外,这项工作还提供了视觉证据,表明在将OMV静脉注射给实验小鼠后数小时内,标记的OMV通过实验小鼠的不同器官。一些标记的OMV甚至穿过了Neuro2A的膜,表明细菌和哺乳动物之间存在王国之间的水平移动性。
The discovery of Replication Competent Circular DNA molecules in mammalian cells and tissues is being linked to debilitating diseases, such as multiple sclerosis (MS), bovine spongiform encephalopathy (BSE), and colorectal cancer (CRC). These circular DNA molecules, otherwise known as bovine meat and milk factors (BMMFs) and Slow Progressive Hidden INfections of variable (X) latency (SPHINX), bear significant (80%) sequence similarity with the plasmids of Acinetobacter baumannii strains. Nanostructures, such as bacterial outer membrane vesicles (OMVs) serve as vehicles for transporting biomolecular cargo and have the potential to facilitate interkingdom lateral mobility of DNA. Strengthening the proposed hypothesis, this study demonstrates that OMVs derived from A. baumannii DS002 carrying four plasmids and genome (pTS236) of phage, AbDs1, successfully reached different parts of the body, including the central nervous system, following the injection of fluorescein isothiocyanate (FITC)-labeled OMVs into experimental mice. Out of the four OMV-associated plasmids, three (pTS4586, pTS9900, and pTS134338) were identified within the lumen, and the fourth one (pTS11291) was found on the surface of OMVs. In addition to the indigenous plasmids, the phage-encoded protein, Orf96, anchored on the surface of the OMVs by establishing a strong interaction with the OMV-associated porin, OmpA. Intriguingly, a subset of labeled OMVs, when incubated with Neuro2A cells, translocated across the membrane and reached to the cytoplasmic space of the cells. Collectively, the experimental evidence presented herein underscores the promising potential of OMVs as vehicles for delivering molecular cargo containing plasmids and phage genomes to diverse mammalian tissues and cells.
OBJECTIVE: Several independent studies have demonstrated the existence of replication competent circular DNA molecules of bacterial and viral origin in mammalian cells and tissues. However, studies about their origin and lateral mobility to mammalian cells are scarce. Our work describes the existence of circular DNA, similar to that of DNA molecules identified in mammalian cells, OMVs derived from soil isolate of A. baumannii DS002. Furthermore, the work also provides visual evidence that demonstrates the passage of labeled OMVs to different organs of experimental mice within hours after intravenously administering OMVs into experimental mice. Some of the labeled OMVs have even crossed the membrane of Neuro2A, suggesting the existence of interkingdom horizontal mobility between bacteria and mammals.