Cyclic electron flow around photosystem I is essential for photosynthesis

@article{Munekage2004CyclicEF,
  title={Cyclic electron flow around photosystem I is essential for photosynthesis},
  author={Y. Munekage and Mihoko Hashimoto and C. Miyake and K. Tomizawa and T. Endo and M. Tasaka and T. Shikanai},
  journal={Nature},
  year={2004},
  volume={429},
  pages={579-582}
}
Photosynthesis provides at least two routes through which light energy can be used to generate a proton gradient across the thylakoid membrane of chloroplasts, which is subsequently used to synthesize ATP. In the first route, electrons released from water in photosystem II (PSII) are eventually transferred to NADP+ by way of photosystem I (PSI). This linear electron flow is driven by two photochemical reactions that function in series. The cytochrome b6f complex mediates electron transport… Expand
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