Download MendeleyCryo-EM structure of the NDH-PSI-LHCI supercomplex from Spinacia oleracea.
Introini, B., Hahn, A., Kuhlbrandt, W.(2025) Nat Struct Mol Biol
- PubMed: 39856350
- DOI: https://doi.org/10.1038/s41594-024-01478-1
- Primary Citation of Related Structures:
9GRX - PubMed Abstract:
The nicotinamide adenine dinucleotide phosphate (NADPH) dehydrogenase (NDH) complex is crucial for photosynthetic cyclic electron flow and respiration, transferring electrons from ferredoxin to plastoquinone while transporting H + across the chloroplast membrane. This process boosts adenosine triphosphate production, regardless of NADPH levels. In flowering plants, NDH forms a supercomplex with photosystem I, enhancing its stability under high light. We report the cryo-electron microscopy structure of the NDH supercomplex in Spinacia oleracea at a resolution of 3.0-3.3 Å. The supercomplex consists of 41 protein subunits, 154 chlorophylls and 38 carotenoids. Subunit interactions are reinforced by 46 distinct lipids. The structure of NDH resembles that of mitochondrial complex I closely, including the quinol-binding site and an extensive internal aqueous passage for proton translocation. A well-resolved catalytic plastoquinone (PQ) occupies the PQ channel. The pronounced structural similarity to complex I sheds light on electron transfer and proton translocation within the NDH supercomplex.
Organizational Affiliation:
Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
