論文 - 詳細
| RRC ID | 30402 |
|---|---|
| 著者 | Krupnik T, Kotabová E, van Bezouwen LS, Mazur R, Garstka M, Nixon PJ, Barber J, Kaňa R, Boekema EJ, Kargul J. |
| タイトル | A reaction center-dependent photoprotection mechanism in a highly robust photosystem II from an extremophilic red alga, Cyanidioschyzon merolae. |
| ジャーナル | J Biol Chem |
| Abstract |
Members of the rhodophytan order Cyanidiales are unique among phototrophs in their ability to live in extremely low pH levels and moderately high temperatures. The photosynthetic apparatus of the red alga Cyanidioschyzon merolae represents an intermediate type between cyanobacteria and higher plants, suggesting that this alga may provide the evolutionary link between prokaryotic and eukaryotic phototrophs. Although we now have a detailed structural model of photosystem II (PSII) from cyanobacteria at an atomic resolution, no corresponding structure of the eukaryotic PSII complex has been published to date. Here we report the isolation and characterization of a highly active and robust dimeric PSII complex from C. merolae. We show that this complex is highly stable across a range of extreme light, temperature, and pH conditions. By measuring fluorescence quenching properties of the isolated C. merolae PSII complex, we provide the first direct evidence of pH-dependent non-photochemical quenching in the red algal PSII reaction center. This type of quenching, together with high zeaxanthin content, appears to underlie photoprotection mechanisms that are efficiently employed by this robust natural water-splitting complex under excess irradiance. In order to provide structural details of this eukaryotic form of PSII, we have employed electron microscopy and single particle analyses to obtain a 17 Å map of the C. merolae PSII dimer in which we locate the position of the protein mass corresponding to the additional extrinsic protein stabilizing the oxygen-evolving complex, PsbQ'. We conclude that this lumenal subunit is present in the vicinity of the CP43 protein, close to the membrane plane. |
| 巻・号 | 288(32) |
| ページ | 23529-42 |
| 公開日 | 2013-8-9 |
| DOI | 10.1074/jbc.M113.484659 |
| PII | S0021-9258(20)45376-1 |
| PMID | 23775073 |
| PMC | PMC5395030 |
| MeSH | Enzyme Stability Hot Temperature Hydrogen-Ion Concentration Light Peptide Mapping Photosystem II Protein Complex / chemistry* Photosystem II Protein Complex / metabolism Rhodophyta / enzymology* |
| IF | 4.238 |
| 引用数 | 35 |
| WOS 分野 | BIOCHEMISTRY & MOLECULAR BIOLOGY |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 最多言及媒体 | Wikipedia |
| 各媒体での言及数の合計 | 4 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 藻類 | NIES-1332 |