Structure of the far-red light utilizing photosystem I of Acaryochloris marina
Acaryochloris marina is one of the cyanobacteria that can use far-red light to drive photochemical reactions for oxygenic photosynthesis. Here, we report the structure of the photosystem I reaction center of A. marina determined by cryo-electron microscopy at 2.5 Å resolution. The structure reveals an arrangement of electron carriers and light-harvesting pigments different from other type I reaction centers. The paired chlorophyll, so-called special pair, of P740 is a dimer of chlorophyll d/d′ and the primary electron acceptor is pheophytin a, a metal-less chlorin different from the chlorophyll a common to all other type I reaction centers. Here we show the architecture of the photosystem I reaction center is composed of 11 subunits and identify key components that help explain how the low energy yield from far-red light is efficiently utilized for driving oxygenic photosynthesis.
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Supplementary Information
Posted 21 Jan, 2021
Structure of the far-red light utilizing photosystem I of Acaryochloris marina
Posted 21 Jan, 2021
Acaryochloris marina is one of the cyanobacteria that can use far-red light to drive photochemical reactions for oxygenic photosynthesis. Here, we report the structure of the photosystem I reaction center of A. marina determined by cryo-electron microscopy at 2.5 Å resolution. The structure reveals an arrangement of electron carriers and light-harvesting pigments different from other type I reaction centers. The paired chlorophyll, so-called special pair, of P740 is a dimer of chlorophyll d/d′ and the primary electron acceptor is pheophytin a, a metal-less chlorin different from the chlorophyll a common to all other type I reaction centers. Here we show the architecture of the photosystem I reaction center is composed of 11 subunits and identify key components that help explain how the low energy yield from far-red light is efficiently utilized for driving oxygenic photosynthesis.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5