Approved FOM programme
|Title||The thylakoid membrane - a dynamic switch (TM)|
|Executive organisational unit||BUW|
|Programme management||Prof.dr. R. van Grondelle|
|Cost estimate||M€ 2.6|
The aim of the programme is to study the structure and dynamics of thylakoid membranes and its constituent pigment proteins under varying conditions. The main objectives are:
- Study the switching thylakoid membrane at nm-mm length scale and at fs-sec timescale.
- Develop quantitative models to understand the dynamic function, structure and organization of this biological switch at nm-mm length scale and at fs-sec timescale.
- Manipulate the switching thylakoid at atomic, molecular, supra-molecular and cellular level.
Background, relevance and implementation
Photosynthesis is the biological process performed by plants, algae and photosynthetic bacteria to convert the energy of sunlight into a form that can be used by the organism to grow, maintain, multiply. The ultimate efficiency of photosynthesis relies heavily on the ability of the photosynthetic apparatus to respond to extreme 'stress' conditions: intense light, drought, cold. The photosynthetic thylakoid membrane (TM) that contains all the essential components reacts strongly to stress conditions by switching rapidly between 'photosynthetic' and 'photo-protective' states by reorganizing the TM. Understanding the photosynthetic process thus requires exploring the dynamics of the system and especially the functional and structural flexibility of the TM and its constituting pigment-proteins. The elucidation of the molecular biophysical feed-back mechanism(s), which relate the sensing of photosynthetic activity to the re-organization of the membrane architecture, is a major contribution to understanding the efficiency of photosynthesis in oxygenic organisms in general. It is essential for understanding abiotic stress tolerance, which is relevant for developing strategies to optimize agriculture and biofuel production.
A set of 8 projects has been defined covering all aspects of this problem from the molecular level to the intact chloroplast. (1) biochemistry to produce photosynthetic complexes, membrane fragments and (reconstituted) membranes of increasing complexity and intactness combined with genetics to produce selectively and intelligently genetically engineered materials; (2) EM and EM-tomography to identify single complexes/membrane fragments and their organization in the membrane; (3) single molecule emission spectroscopy to identify the switching capacity of photosynthetic complexes of increasing complexity; (4,5) fluorescence lifetime imaging (4) and non-linear (5) microscopy on photosynthetic membranes in vitro and in vivo to identify the functional organization at high resolution; (6) solid state NMR to study the dynamics of proteins and lipids in the TM; (7) in vivo NMR to understand the role of transport phenomena and membrane phase changes and (8) molecular dynamics simulations to make a quantitative model of the TM that relates the dynamic structure of supercomplexes/ membrane fragments/-membranes to the physical-chemical properties of the pigment proteins, lipid composition and functionality.
The final evaluation of this programme will consist of a self-evaluation initiated by the programme leader and is foreseen for 2016.
Please find a research highlight that was achieved in 2013 within this FOM programme here.