Extracellular pyruvate: sensing, uptake, and significance for gamma-proteobacteria

细胞外丙酮酸：γ-变形菌的传感、摄取和意义

• 批准号: 432402323
• 负责人: Professorin Dr. Kirsten Jung
• 金额: --
• 依托单位: Abteilung Mikrobiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/432402323?language=en
• 关键词: Extracellular; pyruvate; sensing; uptake; significance

Pyruvate, a central metabolite, is excreted by many bacteria into the environment as a result of overflow metabolism. In previous studies we identified a network of pyruvate sensors and transporters, which is activated in Escherichia coli and other gamma-proteobacteria under nutrient limitation to reuptake this metabolite. The first part of the project is dedicated to the detailed elucidation of the structure and function of key components of this network in E. coli. The studies shall focus (1.) on the investigation of the unusual phosphorylation-independent signal transduction within the pyruvate-sensing histidine kinase/response regulator systems BtsS/BtsR and YdpA/YpdB of E. coli and their structural analysis. (2.) The 3D structures of the two pyruvate transporters BstT and CstA of E. coli shall be resolved. Both transporters belong to the poorly investigated CstA transporter family. CstA, the name-giving protein of the family, will be biochemically characterized with respect to substrate specificity, kinetics and energization for the first time. Although the pyruvate sensory network is widespread in gamma-proteobacteria, there are significant differences in design and functionality among genera. For example, bacteria of the genus Vibrio excrete significantly more pyruvate than Escherichia, but have a very simple system for pyruvate sensing and uptake. Therefore, in the second part of the project, the studies will be extended to Vibrio campbellii (previously V. harveyi), a model bacterium for quorum sensing. The work shall focus (3.) on the clarification of the biological significance of pyruvate sensing and transport in V. campbellii. Furthermore, (4.) V. campbellii will be used as a model organism to investigate the relevance of extracellular pyruvate for microbial interactions. We will address the question whether bacteria compete for pyruvate as a nutrient or use the compound to attract and kill other species. Work on this project is expected to contribute to a better understanding of sensing and uptake of the primary metabolite pyruvate and its significance for microbial interactions.

丙酮酸是一种中心代谢产物，许多细菌通过溢流代谢将丙酮酸排泄到环境中。在以前的研究中，我们确定了丙酮酸传感器和转运蛋白的网络，这是激活大肠杆菌和其他γ-变形菌在营养限制下再摄取这种代谢产物。第一部分详细阐述了E.杆菌研究重点是（1.）研究了大肠杆菌组氨酸敏感的组氨酸激酶/反应调节系统BtsS/BtsR和YdpA/YpdB中不寻常的磷酸化非依赖性信号转导。大肠杆菌中进行结构分析。（2.）对大肠杆菌丙酮酸转运蛋白BstT和CstA的三维结构进行了研究。大肠杆菌应解决。这两种转运蛋白都属于研究不足的CstA转运蛋白家族。CstA，该家族的命名蛋白，将首次在底物特异性，动力学和生物化学方面进行表征。虽然丙酮酸感觉网络在γ-变形菌中广泛存在，但在设计和功能上存在显着差异。例如，弧菌属的细菌比埃希氏菌分泌显著更多的丙酮酸，但具有非常简单的丙酮酸感测和摄取系统。因此，在该项目的第二部分，研究将扩展到Vibrio campbellii（以前的V. harveyi），一种群体感应的模式细菌。工作重点（三）关于澄清V. campbellii中丙酮酸传感和运输的生物学意义。此外，（4.）坎氏弧菌将被用作模式生物，以研究胞外丙酮酸与微生物相互作用的相关性。我们将讨论细菌是否竞争丙酮酸作为营养物质或使用该化合物来吸引和杀死其他物种的问题。预计该项目的工作将有助于更好地了解初级代谢产物丙酮酸的感测和摄取及其对微生物相互作用的意义。