8ACA

SDBC DR_0644 subunit, only-Cu Superoxide Dismutase

8ACA の概要

• エントリーDOI: 10.2210/pdb8aca/pdb
• EMDBエントリー: 14715
• 分子名称: DR_0644, only-Cu Superoxide Dismutase, COPPER (II) ION (2 entities in total)
• 機能のキーワード: superoxide dismutase, s-layer deinoxanthin-binding complex, deinococcus radiodurans, cell envelop, s-layer, metal binding protein
• 由来する生物種: Deinococcus radiodurans R1
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 62857.49

構造登録者

Farci, D.,Piano, D. (登録日: 2022-07-05, 公開日: 2023-04-12, 最終更新日: 2024-07-24)

主引用文献

Farci, D.,Graca, A.T.,Iesu, L.,de Sanctis, D.,Piano, D.
The SDBC is active in quenching oxidative conditions and bridges the cell envelope layers in Deinococcus radiodurans.
J.Biol.Chem., 299:102784-102784, 2023

PubMed Abstract: Deinococcus radiodurans is known for its remarkable ability to withstand harsh stressful conditions. The outermost layer of its cell envelope is a proteinaceous coat, the S-layer, essential for resistance to and interactions with the environment. The S-layer Deinoxanthin-binding complex (SDBC), one of the main units of the characteristic multilayered cell envelope of this bacterium, protects against environmental stressors and allows exchanges with the environment. So far, specific regions of this complex, the collar and the stalk, remained unassigned. Here, these regions are resolved by cryo-EM and locally refined. The resulting 3D map shows that the collar region of this multiprotein complex is a trimer of the protein DR_0644, a Cu-only superoxide dismutase (SOD) identified here to be efficient in quenching reactive oxygen species. The same data also showed that the stalk region consists of a coiled coil that extends into the cell envelope for ∼280 Å, reaching the inner membrane. Finally, the orientation and localization of the complex are defined by in situ cryo-electron crystallography. The structural organization of the SDBC couples fundamental UV antenna properties with the presence of a Cu-only SOD, showing here coexisting photoprotective and chemoprotective functions. These features suggests how the SDBC and similar protein complexes, might have played a primary role as evolutive templates for the origin of photoautotrophic processes by combining primary protective needs with more independent energetic strategies.

PubMed: 36502921
DOI: 10.1016/j.jbc.2022.102784

実験手法

ELECTRON MICROSCOPY (2.54 Å)