Interactions in the bacterial pathobiome associated with crown gall disease: coexistence or competition?

与冠瘿病相关的细菌病原体组的相互作用：共存还是竞争？

• 批准号: 429677233
• 负责人: Dr. Nemanja Kuzmanovic
• 金额: --
• 依托单位: Institut für Epidemiologie und Pathogendiagnostik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/429677233?language=en
• 关键词: Interactions; bacterial; pathobiome; associated; crown

Crown gall caused by tumorigenic Rhizobiaceae species (agrobacteria) is a widespread and economically important plant disease affecting numerous agricultural crops. Agrobacteria carry a tumor-inducing (Ti) plasmid that is essential for pathogenicity, but also confer utilization of tumor-specific metabolites called opines.We have recently resolved etiology of the crown gall disease of rhododendron. In this respect, a novel group of tumorigenic Rhizobium sp. that seems to harbor a new type of Ti plasmid was discovered. Crown gall tumors on rhododendron were also inhabited by nontumorigenic Agrobacterium spp. carrying a specific opine-catabolic (OC) plasmid. This project aims to further decipher the bacterial pathobiome of crown gall tumors of rhododendron and to elucidate the genome- and plasmid-encoded diversity and functions of the dominant bacterial populations by using both cultivation-dependent and -independent methods.Crown gall disease of rhododendron will be also used as a model to study the ecology and dynamics of interspecies interactions in tumors. For this purpose, greenhouse experiments with tomato (test plant) and rhododendron (original host plant) will be performed. Plants will be inoculated with either tumorigenic Rhizobium sp. or nonpathogenic Agrobacterium sp., as well as with both of these bacteria mixed in different ratios. Inoculant strains will be monitored at different time points by using nucleic acid-based and microscopy methods. In this way, the hypothesis that tumorigenic Rhizobium sp. or nonpathogenic Agrobacterium sp. systemically colonize inoculated plants and are intimately co-localized in tumor tissue will be tested. It is further hypothesized that they stably coexist within the pathobiome of crown gall tumors. Consequently, it is assumed that the population of the pathogen is maintained in the multispecies community and not outcompeted by nonpathogenic opine-catabolizing bacteria. Moreover, the objective of this project is to investigate the effects of the interspecies interactions on disease development.The project combines different advanced approaches from plant pathology and microbial ecology and will contribute to the better mechanistic understanding of the composition, succession and colonization of the pathobiome of crown gall tumors. Moreover, it will also provide an essential basis for the improvement of existing and the exploration of new approaches for management of crown gall disease.

由根瘤科致癌菌种(农杆菌)引起的冠瘤是一种广泛存在的、具有重要经济意义的植物病害，影响着多种农作物。农杆菌携带一种肿瘤诱导(Ti)质粒，它对致病性是必不可少的，但也提供了对肿瘤特异性代谢物Opins的利用。我们最近解决了杜鹃冠瘤病的病原学。在这方面，发现了一株新的致瘤根瘤菌。似乎含有一种新型的钛质粒被发现。杜鹃上的冠瘤也被非致瘤性的农杆菌种寄生。携带一种特定的视神经分解代谢(OC)质粒。本项目旨在进一步破译杜鹃冠瘤的细菌病原体，并利用依赖培养和独立培养的方法阐明优势细菌种群的基因组和质粒编码的多样性和功能。还将以杜鹃冠瘤为模型来研究肿瘤中物种间相互作用的生态学和动力学。为此，将进行番茄(试验植物)和杜鹃(原始寄主植物)的温室试验。植物将接种致瘤根瘤菌。或非致病农杆菌，以及与这两种细菌以不同的比例混合。将使用核酸和显微镜方法在不同的时间点监测接种菌株。由此，提出了致瘤根瘤菌的假说。或非致病农杆菌属。系统地对接种的植物进行定植，并密切共存于肿瘤组织将进行测试。这进一步假设，它们稳定地共存于冠胆肿瘤的病原体中。因此，假设病原体的种群维持在多物种群落中，而不是被非致病性的视神经分解代谢细菌所竞争。此外，该项目的目的是研究物种间的相互作用对疾病发展的影响。该项目结合了植物病理学和微生物生态学的不同先进方法，将有助于从机制上更好地了解冠胆肿瘤病原菌的组成、演替和定植。此外，还将为改进现有的冠胆疾病的治疗方法和探索新的治疗方法提供必要的依据。