9HD7

Cryo-EM structure of photosystem II C2S2M2L2 supercomplex from the green alga Chlorella ohadii

これはPDB形式変換不可エントリーです。

9HD7 の概要

• エントリーDOI: 10.2210/pdb9hd7/pdb
• EMDBエントリー: 52056
• 分子名称: Chlorophyll a-b binding protein Lhcbm-I, Cytochrome b559 subunit alpha, Cytochrome b559 subunit beta, ... (50 entities in total)
• 機能のキーワード: supercomplex, photosynthesis, chlorophyll, algae, membrane protein
• 由来する生物種: Chlorella ohadii; 詳細
• タンパク質・核酸の鎖数: 66
• 化学式量合計: 2098239.03

構造登録者

Kopecny, D.,Kouril, R.,Ardhad, R.,Skalidis, I.,Kastritis, P. (登録日: 2024-11-11, 公開日: 2025-11-12, 最終更新日: 2026-01-21)

主引用文献

Arshad, R.,Skalidis, I.,Kopecny, D.,Brabencova, S.,Opatikova, M.,Ilik, P.,Pospisil, P.,Hamdi, F.,Cavar Zeljkovic, S.,Kopecna, M.,Roudnicky, P.,Lazar, D.,Elias, E.,Croce, R.,Kastritis, P.L.,Kouril, R.
Cryo-EM structure of photosystem II supercomplex from a green microalga with extreme phototolerance.
Nat Commun, 17:341-341, 2026

PubMed Abstract: Photosystem II (PSII) is essential for energy conversion during oxygenic photosynthesis in plants and algae. Chlorella ohadii, one of the fastest multiplying green algae, thrives under the harsh desert sun but lacks the standard PSII photoprotective mechanisms involving LhcSR/PsbS proteins or protein phosphorylation. Here, we present the cryo-EM structure of the PSII supercomplex from C. ohadii at 2.9 Å resolution, which is used to determine whether the exceptional resistance to desert conditions has a structural basis in PSII. The structure reveals a distinct PsbO isoform and additional subunits, PsbR and PsbY, which enhance core complex stability through extensive interactions. Furthermore, the trimeric light-harvesting complexes (LHCII) are bound to the PSII core by specific light-harvesting proteins whose down-regulation in response to high-light conditions implies a reduction in the number of bound LHCII trimers. These structural modifications, together with the high accumulation of specific polyamines in the thylakoid membrane, play a key role in maintaining PSII stability and photoprotection, allowing C. ohadii to survive in extreme conditions.

PubMed: 41513636
DOI: 10.1038/s41467-025-65861-2

実験手法

ELECTRON MICROSCOPY (2.95 Å)