4CKB

Vaccinia virus capping enzyme complexed with GTP and SAH

4CKB の概要

• エントリーDOI: 10.2210/pdb4ckb/pdb
• 関連するPDBエントリー: 4CKC 4CKE
• 分子名称: MRNA-CAPPING ENZYME CATALYTIC SUBUNIT, MRNA-CAPPING ENZYME REGULATORY SUBUNIT, S-ADENOSYL-L-HOMOCYSTEINE, ... (5 entities in total)
• 機能のキーワード: transferase-hydrolase complex, trifunctional vaccinia virus mrna capping enzyme, transferase/hydrolase
• 由来する生物種: VACCINIA VIRUS; 詳細
• 細胞内の位置: Virion (Probable): P04298 P04318
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 261798.67

構造登録者

Kyrieleis, O.J.P.,Chang, J.,de la Pena, M.,Shuman, S.,Cusack, S. (登録日: 2014-01-02, 公開日: 2014-03-19, 最終更新日: 2025-12-10)

主引用文献

Kyrieleis, O.J.P.,Chang, J.,De La Pena, M.,Shuman, S.,Cusack, S.
Crystal Structure of Vaccinia Virus Mrna Capping Enzyme Provides Insights Into the Mechanism and Evolution of the Capping Apparatus.
Structure, 22:452-, 2014

PubMed Abstract: Vaccinia virus capping enzyme is a heterodimer of D1 (844 aa) and D12 (287 aa) polypeptides that executes all three steps in m(7)GpppRNA synthesis. The D1 subunit comprises an N-terminal RNA triphosphatase (TPase)-guanylyltransferase (GTase) module and a C-terminal guanine-N7-methyltransferase (MTase) module. The D12 subunit binds and allosterically stimulates the MTase module. Crystal structures of the complete D1⋅D12 heterodimer disclose the TPase and GTase as members of the triphosphate tunnel metalloenzyme and covalent nucleotidyltransferase superfamilies, respectively, albeit with distinctive active site features. An extensive TPase-GTase interface clamps the GTase nucleotidyltransferase and OB-fold domains in a closed conformation around GTP. Mutagenesis confirms the importance of the TPase-GTase interface for GTase activity. The D1⋅D12 structure complements and rationalizes four decades of biochemical studies of this enzyme, which was the first capping enzyme to be purified and characterized, and provides new insights into the origins of the capping systems of other large DNA viruses.

PubMed: 24607143
DOI: 10.1016/J.STR.2013.12.014

実験手法

X-RAY DIFFRACTION (2.8 Å)