Cross-species computational analysis of the PMF and its key characteristics

PMF 及其关键特征的跨物种计算分析

• 批准号: 524784919
• 负责人: Professorin Dr. Anna Matuszynska
• 金额: --
• 依托单位: Juniorprofessur für Computational Life Science
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/524784919?language=en
• 关键词: Cross; species; computational; analysis; PMF

Photosynthetic proton motive force (PMF) across the thylakoid membrane plays a pivotal role in the regulation of organisms’ energy metabolism. The number of interdependent processes and possible cross-talks between reactions that generate, modulate and depend on PMF are astonishing and their combined effect on the cell’s bioenergetics leads to a nonlinear complexity. Hence, a rigorous framework that allows for a systematic disentangling of its complexity is necessary to develop concepts on how the PMF is achieved and regulated across photosynthetic species. Computational, mechanistic models of the photosynthetic electron transport chain offer a quantitative framework that enables comparative studies. Numerous models of photosynthesis describe PMF, but many of them focus solely on its pH-dependent component (ΔpH), mainly due to its link to the important photoprotective mechanism named non-photochemical quenching. Energy-dependent quenching releases excess light energy as heat, to protect photosystem II against damage. Yet, the importance of the membrane potential (ΔΨ) in the generation of PMF, and photoprotection, should not be ignored, as the photosynthetic electron transport is highly sensitive to the concentration of ions (e.g., H+, K+, Mg2+ and Cl−). Ion transport proteins in the thylakoid membrane, such as KEA3, allow for an out-flux of H+ with a counter-in-flux of cations into the membrane, affecting the contribution of proton-based or potential-driven components of PMF. By dynamic fine-tuning of the two PMF components, photosynthetic organisms can dynamically adapt to environmental changes and balance their energy production to meet their energy demand. In this project, we aim to construct a unifying theoretical framework describing the dynamics of PMF for numerous classes of photosynthetic organisms studied by the GoPMF partners, ranging from cyanobacteria to green microalgae to higher plants. Building on the previously constructed mathematical models of the photosynthetic electron transport chain, we will fully explore the modular design of our models to create a blueprint for PMF regulation. Within this framework, we will be able to systematically investigate the effect of PMF partitioning on the photosynthetic dynamics and perform cross-species comparisons to generate novel hypotheses regarding PMF regulation. Combined with the collected experimental work, our model will guide the experiment in the light-driven production of hydrogen in cyanobacteria. Our ambition is to construct a platform where Aims 1,2,4, and 5 of the GoPMF can be further explored.

通过类囊体膜的光合质子动力（PMF）在调节生物体能量代谢中起着关键作用。产生、调节和依赖PMF的反应之间相互依赖的过程和可能的交叉对话的数量是惊人的，它们对细胞生物能量学的综合影响导致了非线性的复杂性。因此，有必要建立一个严格的框架，允许系统地解开其复杂性，以发展关于PMF如何在光合作用物种中实现和调节的概念。光合作用电子传递链的计算机制模型为比较研究提供了定量框架。许多光合作用模型描述了PMF，但其中许多只关注其ph依赖性成分（ΔpH），主要是因为它与重要的光保护机制非光化学猝灭有关。能量依赖猝灭释放多余的光能作为热，以保护光系统II免受损害。然而，膜电位（ΔΨ）在PMF生成和光保护中的重要性不应被忽视，因为光合电子传递对离子（如H+， K+， Mg2+和Cl−）的浓度高度敏感。类囊体膜中的离子转运蛋白，如KEA3，允许H+的流出和阳离子的反向流入膜中，影响质子基或电位驱动的PMF组分的贡献。通过对两个PMF组分的动态微调，光合生物可以动态适应环境变化，平衡其能量生产以满足其能量需求。在这个项目中，我们的目标是构建一个统一的理论框架，描述由GoPMF合作伙伴研究的许多类别的光合生物的PMF动力学，从蓝藻到绿色微藻再到高等植物。在之前构建的光合电子传递链数学模型的基础上，我们将充分探索模型的模块化设计，为PMF调控创建蓝图。在这个框架内，我们将能够系统地研究PMF分配对光合动力学的影响，并进行跨物种比较，以产生关于PMF调节的新假设。结合收集到的实验工作，我们的模型将指导蓝藻光驱动产氢实验。我们的目标是建立一个平台，进一步探索GoPMF的目标1、2、4和5。