Biological role of outer membrane vesicle-associated small proteins of the phytopathogen Agrobacterium tumefaciens

植物病原体农杆菌外膜囊泡相关小蛋白的生物学作用

• 批准号: 379643560
• 负责人: Dr. Meriyem Aktas, Ph.D.
• 金额: --
• 依托单位: Lehrstuhl für Biologie der Mikroorganismen
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/379643560?language=en
• 关键词: Biological; role; outer; membrane; vesicle

Bacterial extracellular membrane vesicles are considered as novel players in various cell communication systems. Outer membrane vesicles (OMVs) are released from the outer membrane of many Gram-negative bacteria. The cargo of these extracellular nanostructures comprises distinct biomolecules such as small compounds, genetic material, proteins and peptides, which are involved in intra- and inter-species communication and pathogenicity.We have recently demonstrated that the phytopathogen Agrobacterium tumefaciens, the causative agent of crown gall disease, releases OMVs into the culture supernatant during growth. A proteome study of the OMV fractions obtained under different growth conditions identified about 60 proteins including the two conserved small proteins Atu2614 and Atu8019 with unknown functions. Both proteins contain a predicted N-terminal signal peptidase II sequence with a C-terminal consensus lipobox, a hallmark of lipoproteins. The mature form of Atu2614 is expected to contain 67 aa and comprises a highly hydrophobic domain with several extended glycine-zipper motifs commonly found in pore-forming membrane proteins. Atu8019 (mature size: 32 aa) shares sequence similarities to entericidin antidote/toxin peptides.In this proposal we aim at elucidating the biological roles of these two OMV-associated small proteins in Agrobacterium by combining genetic and biochemical approaches. With these studies we expect to obtain new valuable insights into the physiological relevance of OMV-associated small lipoproteins in bacteria.

细菌细胞外膜囊泡被认为是各种细胞通讯系统中的新型参与者。外膜囊泡（OMV）是从许多革兰氏阴性细菌的外膜释放出来的。这些细胞外纳米结构的货物包括不同的生物分子，如小的化合物，遗传物质，蛋白质和肽，这是在内部和物种间的通信和pathogenicity.We最近已经证明，植物病原体根癌农杆菌，冠瘿病的病原体，释放OMV到培养上清液在生长过程中。在不同的生长条件下获得的OMV组分的蛋白质组研究确定了约60个蛋白质，包括两个保守的小蛋白Atu 2614和Atu 8019与未知的功能。这两种蛋白质都含有一个预测的N-末端信号肽酶II序列，C-末端共有脂盒，脂蛋白的标志。预期Atu 2614的成熟形式含有67个氨基酸，并且包含具有通常在孔形成膜蛋白中发现的几个延伸的甘氨酸拉链基序的高度疏水结构域。Atu 8019（成熟长度：32 aa）与肠毒素解毒肽/毒素肽序列相似，本研究旨在通过遗传学和生物化学相结合的方法阐明这两个OMV相关小蛋白在农杆菌中的生物学作用。通过这些研究，我们期望获得新的有价值的见解OMV相关的小脂蛋白在细菌中的生理相关性。