Enhancing plant productivity using engineered microbes

利用工程微生物提高植物生产力

• 批准号: 2462758
• 金额: --
• 依托单位: Newcastle University
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2462758
• 关键词: Enhancing; plant; productivity; using; engineered

The productivity and resilience of agricultural systems face multiple challenges including climate change, increasing demand and the need for more sustainable sources of fertilizers. The biotechnological potential of microbe-plant interactions have been purposed in the agronomic area. Endophytes, microbes that inhabit internal tissues of plants without causing disease, are able to modulate plant development, increase plant stress tolerance and disease resistance, suppress virulence in pathogens and development of competitor plant species and carry nutrients from the soil into plants. As a result, there is a growing interest in using plant growth-promoting bacteria (PGPB) as an alternative to reduce fertilizers, fungicides, insecticides and herbicides.The objective of this project is to engineer plant endophytic relationships without genetically manipulating the host plant but developing a bacterial synthetic biology model organism. For that purpose, the interactions between a gram negative rhizospheric bacteria (Pseudomonas sp. CT364) and the plant Arabidopsis Thaliana will be studied and engineered. This strain was isolated recently by one of the supervisors and the ability to colonize and stimulate A. thaliana growth was confirmed as well as other PGP features like phosphorous solubilization and plant hormone and siderophore synthesis and release. The project has three different objectives which will be completed in different laboratory rotations. The first objective is to study the strain bacterial genomics in order to define which genomic features are related or involved in the endophytic lifestyle and plant growth enhancement. From the sequencing reads of the strain the genome has been annotated revealing the main traits of the strain. After that, a phylogenetic study, genome mining and a comparative analysis have been performed unravelling a high number of potential PGP traits. Moreover, similarities and divergences between other endophyte and pathogen Pseudomonas strains were outlined to highlight the unique set of genes that may possibly account for specificity in niche occupation. The second objective is based into develop a molecular toolkit of the strain in order to optimize culture conditions, bacterial transformation, bacterial genome engineering, bacterial characterization, plant inoculation procedures as well as characterizing safety potential risks as inoculant, reporter genes, origins of replication and selectable markers required for reproducible bioengineering. At the end of this stage, the future and definitive research and engineering method will be stablished depending on the in vivo/vitro confirmed strain features and the potentially modifiable traits in order to create a benefit in plants. The third objective is to examine the plant (A. thaliana) responses and signalling to strain colonization (P. sp. CT364) and the changes created by the engineered strains. For that, short-term signalling and long-term developmental physiological and morphological changes will be characterized. As a result, a model plant/endophyte relationship will be readily and rapidly engineered to introduce new functionality to the plant host and to probe the molecular relationships between plants and their microbiome.Overall, the Pseudomonas sp. CT364 genome provides information to deeper understand the molecular, physiological and biochemical characteristics of plant growth promotion and protection. A combination of transcriptomics, metabolomics, mutagenesis and genome engineering will allow assigning new functions to putative genes and pathways, assess the metabolic potential of the strain and enhance and create bacterial traits that promote a benefit to the plant. These findings can develop strategies to profit from the use of endophytic bacteria to improve plant health and biomass applicable in agriculture in sustainable way.

农业系统的生产力和复原力面临多重挑战，包括气候变化、需求增加以及对更可持续的肥料来源的需求。微生物-植物相互作用的生物技术潜力已被应用于农业领域。内生菌是指存在于植物内部组织而不引起疾病的微生物，能够调节植物发育，提高植物的胁迫耐受性和抗病性，抑制病原体的毒力和竞争植物物种的发育，并将营养物质从土壤中携带到植物中。因此，利用植物生长促进细菌（plant growth promoting bacteria，PGPB）作为减少化肥、杀菌剂、杀虫剂和除草剂用量的替代品越来越受到人们的关注。本项目的目标是在不对宿主植物进行遗传操作的情况下，构建一种细菌合成生物学模式生物。为此，将研究和工程化革兰氏阴性根际细菌（假单胞菌CT 364）和植物拟南芥之间的相互作用。该菌株是最近由一位监管人员分离的，其定殖和刺激A。证实了拟南芥生长以及其它PGP特征，如磷溶解和植物激素和铁载体的合成和释放。该项目有三个不同的目标，将在不同的实验室轮换中完成。第一个目标是研究菌株细菌基因组学，以确定哪些基因组特征与内生生活方式和植物生长增强相关或参与其中。根据菌株的测序读数，基因组已被注释，揭示了菌株的主要性状。之后，进行了系统发育研究、基因组挖掘和比较分析，揭示了大量潜在的PGP性状。此外，其他内生菌和病原体假单胞菌菌株之间的相似性和分歧进行了概述，以突出独特的一组基因，可能占在生态位占领的特异性。第二个目标是开发菌株的分子工具包，以优化培养条件，细菌转化，细菌基因组工程，细菌表征，植物接种程序以及表征可再生生物工程所需的接种物，报告基因，复制起点和选择标记的安全潜在风险。在该阶段结束时，将根据体内/体外确认的菌株特征和潜在的可修饰性状建立未来和确定的研究和工程方法，以便在植物中产生益处。第三个目标是检查植物（A。拟南芥）对菌株定殖（P.sp.CT364）的响应和信号传导以及由工程菌株产生的变化。为此，将表征短期信号传导和长期发育生理和形态变化。因此，植物/内生菌关系的模型将被容易且快速地工程化，以向植物宿主引入新的功能，并探测植物与其微生物组之间的分子关系。总体而言，假单胞菌CT 364基因组提供了信息，以更深入地理解植物生长促进和保护的分子、生理和生化特征。转录组学、代谢组学、诱变和基因组工程的组合将允许为推定的基因和途径分配新的功能，评估菌株的代谢潜力，并增强和创造促进植物益处的细菌性状。这些发现可以制定策略，从使用内生细菌中获益，以可持续的方式改善植物健康和农业生物量。