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Structure of the far-red light utilizing photosystem I of Acaryochloris marina.

ABSTRACT: Acaryochloris marina is one of the cyanobacterial species that can use far-red light to drive photochemical reactions for oxygenic photosynthesis. Here, we report the structure of A. marina photosystem I (PSI) reaction center, determined by cryo-electron microscopy at 2.58 Å resolution. The structure reveals an arrangement of electron carriers and light-harvesting pigments distinct from other type I reaction centers. The paired chlorophyll, or special pair (also referred to as P740 in this case), is a dimer of chlorophyll d and its epimer chlorophyll d'. The primary electron acceptor is pheophytin a, a metal-less chlorin. We show the architecture of this PSI reaction center is composed of 11 subunits and we identify key components that help explain how the low energy yield from far-red light is efficiently utilized for driving oxygenic photosynthesis.

SUBMITTER: Hamaguchi T

PROVIDER: S-EPMC8058080 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Structure of the far-red light utilizing photosystem I of Acaryochloris marina.

Hamaguchi Tasuku T Kawakami Keisuke K Shinzawa-Itoh Kyoko K Inoue-Kashino Natsuko N Itoh Shigeru S Ifuku Kentaro K Yamashita Eiki E Maeda Kou K Yonekura Koji K Kashino Yasuhiro Y

Nature communications 20210420 1

Acaryochloris marina is one of the cyanobacterial species that can use far-red light to drive photochemical reactions for oxygenic photosynthesis. Here, we report the structure of A. marina photosystem I (PSI) reaction center, determined by cryo-electron microscopy at 2.58 Å resolution. The structure reveals an arrangement of electron carriers and light-harvesting pigments distinct from other type I reaction centers. The paired chlorophyll, or special pair (also referred to as P740 in this case) ...[more]

PMID: 33879791

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