Project Details
Projekt
Coordination Funds
Applicant
Professor Dr. Michael Hippler
Subject Area
Plant Biochemistry and Biophysics
Term
since 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 507704013
The proton motive force (PMF) is at the heart of energy metabolism and fuels most cellular functions. It is universal as the genetic code and has been shaping evolution. The PMF is an electrochemical gradient across a membrane, usually generated by the concerted activity of multiple membrane protein complexes. It separates energy transformation from molecular identities and stochiometric constraints and freely connects and integrates otherwise unrelated cellular processes. This feature has been key for the success of the PMF. While being particularly flexible, the PMF must also be strictly reliable to fuel biochemical reactions and to maintain the cell. To guarantee energy supply, environmental and physiological stimuli must be integrated into PMF regulation. Even though the PMF has been studied intensely, regulatory strategies remain insufficiently understood. Recently, functional imaging and biosensing techniques have uncovered novel, fundamental features of the mitochondrial PMF. While those insights have started to shift the paradigms of our understanding of bioenergetic dynamics, similar insights are lacking for oxygenic photosynthesis. Yet, studying PMF in the context of photosynthesis is particularly well suited as an approach to understand the principles underpinning PMF dynamics, because it is particularly prone to rapid external changes due to fluctuating light in natural habitats. This Research Group (GoPMF) will develop concepts of how the generation and modulation of the PMF is regulated to optimize photosynthetic output in changeable natural environments. Driven by recent discoveries and enabling methodological developments by members of this initiative, we will assess photosynthetic bioenergetics within its context of subcellular organization and physiology. We will make use of cyanobacteria and chloroplasts as in vivo models to dissect mechanisms of rapid PMF adjustment at the posttranslational and physiological level. These insights will be linked with mechanistic and structural analyses of the molecular machines that generate and modulate the PMF. Combining state-of-the-art imaging techniques, with the development of in situ biosensing techniques to monitor bioenergetic characteristics of the PMF live in individual cells, organelles and thylakoids will take our understanding of PMF management into a novel cell biological context. Mechanistic molecular detail into the mechanisms driving PMF dynamics will be gained through fast time-resolved spectroscopy, mass spectrometry and structural biology including cryo-EM and cryo-ET. Extensive genetic engineering will take advantage of the mechanistic conservation and diversity in PMF regulation by cyanobacteria, algae and plants. These functional studies will be flanked by mathematical modeling of the PMF. We expect to establish an understanding of the PMF as a dynamic, responsive and integrated hub that shapes photosynthesis and its adjustment to rapid external changes.
DFG Programme
Research Units
