Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, United States.
Departments of Medicine and Genetic Medicine, Weill Cornell Medicine, 10021, NY, USA.
J Proteomics. 2019 Mar 20;195:125-137. doi: 10.1016/j.jprot.2018.12.029. Epub 2019 Jan 8.
Fusobacterium nucleatum is a Gram-negative bacterium commonly found in the oral cavity and is often involved in periodontal diseases. Recent studies have shown increased F. nucleatum prevalence in colorectal cancer (CRC) tissues, and causal data has linked this bacterium to CRC tumorigenesis. Immune-based approaches to contain, reduce or eradicate its gut colonization may prevent CRC. Outer membrane vesicles (OMVs) are naturally produced by Gram-negative bacteria, typically contain multiple putative virulence factors and may elicit protective immune responses if used as vaccines. Here, OMVs were isolated from F. nucleatum cultures and purified using gradient centrifugation. Proteins contained within the OMVs were identified by nano LC/MS/MS analysis. Of 98 proteins consistently identified from duplicate analyses, 60 were predicted to localize to the outer membrane or periplasm via signal peptide driven translocation. Of these, six autotransporter proteins, which constitute the majority of protein mass of OMVs, were associated with Type V secretion system. In addition, other putative virulence factor proteins with functional domains, including FadA, MORN2 and YadA-like domain, were identified with multiple exposed epitope sites as determined by in silico analysis. Altogether, the non-replicative OMVs of F. nucleatum contain multiple antigenic virulence factors that may play important roles in the design and development of vaccines against F. nucleatum. SIGNIFICANCE: Fusobacterium nulceatum has been proved playing significant role in colorectal carcinogenesis. Outer membrane vesicles are nanoparticles that naturally secreted by Gram-negative bacterial containing various antigenic components, which provides new insight in vaccine development. Understanding the constituents of F. nucleatum OMVs will provide fundamental information and potential strategies for OMV-based F. nucleatum vaccines design. Based on our knowledge this is the first proteomic study of OMVs from F. nucleatum.
具核梭杆菌是一种常见于口腔的革兰氏阴性菌，常与牙周病有关。最近的研究表明，具核梭杆菌在结直肠癌（CRC）组织中的患病率增加，因果数据将这种细菌与 CRC 肿瘤发生联系起来。基于免疫的方法来控制、减少或消除其肠道定植可能预防 CRC。外膜囊泡（OMVs）是革兰氏阴性菌自然产生的，通常包含多个潜在的毒力因子，如果用作疫苗，可能会引发保护性免疫反应。在这里，OMVs 是从具核梭杆菌培养物中分离出来的，并通过梯度离心进行纯化。通过纳升 LC/MS/MS 分析鉴定 OMVs 中包含的蛋白质。在重复分析中一致鉴定的 98 种蛋白质中，有 60 种被预测通过信号肽驱动的易位定位于外膜或周质。在这些蛋白质中，六个自动转运蛋白构成了 OMVs 的大部分蛋白质质量，与类型 V 分泌系统有关。此外，还鉴定到其他具有功能结构域的潜在毒力因子蛋白，包括 FadA、MORN2 和 YadA 样结构域，通过计算机分析确定它们具有多个暴露的抗原表位位点。总之，具核梭杆菌的非复制性 OMVs 包含多个抗原性毒力因子，这些因子可能在具核梭杆菌疫苗的设计和开发中发挥重要作用。意义：具核梭杆菌已被证明在结直肠癌的发生中起着重要作用。外膜囊泡是由革兰氏阴性细菌自然分泌的纳米颗粒，含有各种抗原成分，为疫苗开发提供了新的见解。了解具核梭杆菌 OMVs 的成分将为基于 OMV 的具核梭杆菌疫苗设计提供基础信息和潜在策略。根据我们的知识，这是具核梭杆菌 OMVs 的首次蛋白质组学研究。
