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1.  Solid-state NMR applied to photosynthetic light-harvesting complexes 
Photosynthesis Research  2011;111(1-2):219-226.
This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment–protein and pigment–pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the light-harvesting oligomers induces mutual conformational stress. The protein scaffold produces deformation and electrostatic polarization of the BChl macrocycles and leads to a partial electronic charge transfer between the BChls and their coordinating histidines, which can tune the light-harvesting function. In chlorosome antennae assemblies, the NMR template structure reveals how the chromophores can direct their self-assembly into higher macrostructures which, in turn, tune the light-harvesting properties of the individual molecules by controlling their disorder, structural deformation, and electronic polarization without the need for a protein scaffold. These results pave the way for addressing the next challenge, which is to resolve the functional conformational dynamics of the lhc antennae of oxygenic species that allows them to switch between light-emitting and light-energy dissipating states.
PMCID: PMC3295999  PMID: 21842288
Conformational strain; Electronic structures; Chlorosome; Nonphotochemical quenching
2.  Observation of the solid-state photo-CIDNP effect in entire cells of cyanobacteria Synechocystis 
Photosynthesis Research  2010;104(2-3):275-282.
Cyanobacteria are widely used as model organism of oxygenic photosynthesis due to being the simplest photosynthetic organisms containing both photosystem I and II (PSI and PSII). Photochemically induced dynamic nuclear polarization (photo-CIDNP) 13C magic-angle spinning (MAS) NMR is a powerful tool in understanding the photosynthesis machinery down to atomic level. Combined with selective isotope enrichment this technique has now opened the door to study primary charge separation in whole living cells. Here, we present the first photo-CIDNP observed in whole cells of the cyanobacterium Synechocystis.
PMCID: PMC2882559  PMID: 20094793
Plant photosystems; Photo-CIDNP; Electron transfer; Solid-state NMR
3.  Integration of Catalysis with Storage for the Design of Multi-Electron Photochemistry Devices for Solar Fuel 
Applied Magnetic Resonance  2009;37(1-4):497-503.
Decarbonization of the transport system and a transition to a new diversified energy system that is scalable and sustainable, requires a widespread implementation of carbon-neutral fuels. In biomimetic supramolecular nanoreactors for solar-to-fuel conversion, water-splitting catalysts can be coupled to photochemical units to form complex electrochemical nanostructures, based on a systems integration approach and guided by magnetic resonance knowledge of the operating principles of biological photosynthesis, to bridge between long-distance energy transfer on the short time scale of fluorescence, ~10−9 s, and short-distance proton-coupled electron transfer and storage on the much longer time scale of catalysis, ~10−3 s. A modular approach allows for the design of nanostructured optimized topologies with a tunneling bridge for the integration of storage with catalysis and optimization of proton chemical potentials, to mimic proton-coupled electron transfer processes in photosystem II and hydrogenase.
PMCID: PMC2784072  PMID: 19960066
4.  Magic angle spinning (MAS) NMR: a new tool to study the spatial and electronic structure of photosynthetic complexes 
Photosynthesis Research  2009;102(2-3):415-425.
In the last two decades, Magic Angle Spinning (MAS) NMR has created its own niche in studies involving photosynthetic membrane protein complexes, owing to its ability to provide structural and functional information at atomic resolution of membrane proteins when in the membrane, in the natural environment. The light-harvesting two (LH2) transmembrane complex from Rhodopseudomonas acidophila is used to illustrate the procedure of the technique applicable in photosynthesis research. One- and two-dimensional solid-state NMR experiments involving 13C- and 15N-labeled LH2 complexes allow to make a sequence-specific assignment of NMR signals, which forms the basis for resolving structural details and the assessment of charge transfer, electronic delocalization effects, and functional strain in the ground state.
PMCID: PMC2777226  PMID: 19669927
Magic angle spinning NMR; LH2 complex; Electronic structure; Membrane protein; Isotope labeling

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