chloroplast thylakoid lumen / photosystem I reaction center / photosystem I / photosynthetic electron transport in photosystem I / photosystem I / chlorophyll binding / chloroplast thylakoid membrane / photosynthesis / 4 iron, 4 sulfur cluster binding / electron transfer activity ...chloroplast thylakoid lumen / photosystem I reaction center / photosystem I / photosynthetic electron transport in photosystem I / photosystem I / chlorophyll binding / chloroplast thylakoid membrane / photosynthesis / 4 iron, 4 sulfur cluster binding / electron transfer activity / oxidoreductase activity / iron ion binding / heme binding / magnesium ion binding / metal ion binding 類似検索 - 分子機能
Cytochrome c6 / Cytochrome c, class IC / Cytochrome C oxidase, cbb3-type, subunit III / Photosystem I PsaL, reaction centre subunit XI / Photosystem I, reaction centre subunit XI / Photosystem I PsaL, reaction centre subunit XI superfamily / Photosystem I reaction centre subunit XI / Photosystem I reaction centre subunit VIII / Photosystem I reaction centre subunit VIII / Photosystem I reaction centre subunit VIII superfamily ...Cytochrome c6 / Cytochrome c, class IC / Cytochrome C oxidase, cbb3-type, subunit III / Photosystem I PsaL, reaction centre subunit XI / Photosystem I, reaction centre subunit XI / Photosystem I PsaL, reaction centre subunit XI superfamily / Photosystem I reaction centre subunit XI / Photosystem I reaction centre subunit VIII / Photosystem I reaction centre subunit VIII / Photosystem I reaction centre subunit VIII superfamily / Photosystem I PsaF, reaction centre subunit III / Photosystem I PsaF, reaction centre subunit III superfamily / Photosystem I reaction centre subunit III / Photosystem I PsaD / Photosystem I, reaction centre subunit PsaD superfamily / PsaD / Photosystem I PsaE, reaction centre subunit IV / Photosystem I reaction centre subunit IV / PsaE / Photosystem I PsaJ, reaction centre subunit IX superfamily / Photosystem I PsaJ, reaction centre subunit IX / Photosystem I reaction centre subunit IX / PsaJ / Photosystem I PsaA / Photosystem I protein PsaC / Photosystem I PsaB / Photosystem I PsaA/PsaB, conserved site / Photosystem I psaA and psaB proteins signature. / : / Photosystem I PsaA/PsaB / Photosystem I PsaA/PsaB superfamily / Photosystem I psaA/psaB protein / Electron transport accessory-like domain superfamily / 4Fe-4S dicluster domain / Cytochrome c family profile. / Cytochrome c-like domain / Cytochrome c-like domain superfamily / 4Fe-4S ferredoxin, iron-sulphur binding, conserved site / 4Fe-4S ferredoxin-type iron-sulfur binding region signature. / 4Fe-4S ferredoxin-type iron-sulfur binding domain profile. / 4Fe-4S ferredoxin-type, iron-sulphur binding domain 類似検索 - ドメイン・相同性
Photosystem I reaction center subunit VIII / Photosystem I reaction center subunit XI, chloroplastic / Cytochrome c6, chloroplastic / Photosystem I P700 chlorophyll a apoprotein A2 / Photosystem I P700 chlorophyll a apoprotein A1 / Photosystem I reaction center subunit IV, chloroplastic / Photosystem I reaction center subunit III, chloroplastic / Photosystem I reaction center subunit IX / Photosystem I iron-sulfur center / Photosystem I reaction center subunit II, chloroplastic 類似検索 - 構成要素
ジャーナル: Nat Commun / 年: 2026 タイトル: Cryo-EM structure of Chlamydomonas reinhardtii Photosystem I complexed with cytochrome c. 著者: Yu Ogawa / Gyana Prakash Mahapatra / Yuval Milrad / Michelle Schimpf / Genji Kurisu / Michael Hippler / Jan Michael Schuller / 要旨: Photosynthetic electron transfer relies on small soluble carriers that shuttle electrons between the cytochrome b₆f complex and Photosystem I (PSI). While copper-containing plastocyanin (Pc) serves ...Photosynthetic electron transfer relies on small soluble carriers that shuttle electrons between the cytochrome b₆f complex and Photosystem I (PSI). While copper-containing plastocyanin (Pc) serves this role in plants, the heme protein cytochrome c₆ (Cyt c₆) is also employed in algae and cyanobacteria. Here, we present a cryo-electron microscopy structure of a Cyt c₆:PSI complex from Chlamydomonas reinhardtii. We observe that the heme group of Cyt c₆ is positioned ~11 Å away from P700, stabilized by extensive contacts involving a N-terminal helix-loop-helix motif of PSAF, characteristic of eukaryotic PSI. Notably, the algal Cyt c₆ also retains an arginine residue (R66) which is crucial for cyanobacterial donor:PSI reactions. Our structure reveals the previously uncharacterized interactions involving this residue; it can form a putative electrostatic contact with PsaB-D623 while also contributing to a tri-planar π(cation)-π interactions with adjacent residues. Our findings provide a structural framework for understanding the mechanism and evolution of donor:PSI interactions.