National Institutes of Health/National Institute of Environmental Health Sciences (NIH/NIEHS)
1ZIAES102906
米国
National Institutes of Health/National Institute of Environmental Health Sciences (NIH/NIEHS)
1ZICES103326
米国
National Institutes of Health/National Institute of Environmental Health Sciences (NIH/NIEHS)
1ZIAES101905
米国
引用
ジャーナル: Proc Natl Acad Sci U S A / 年: 2022 タイトル: Mechanism by which T7 bacteriophage protein Gp1.2 inhibits dGTPase. 著者: Bradley P Klemm / Deepa Singh / Cassandra E Smith / Allen L Hsu / Lucas B Dillard / Juno M Krahn / Robert E London / Geoffrey A Mueller / Mario J Borgnia / Roel M Schaaper / 要旨: Levels of the cellular dNTPs, the direct precursors for DNA synthesis, are important for DNA replication fidelity, cell cycle control, and resistance against viruses. encodes a dGTPase (2'- ...Levels of the cellular dNTPs, the direct precursors for DNA synthesis, are important for DNA replication fidelity, cell cycle control, and resistance against viruses. encodes a dGTPase (2'-deoxyguanosine-5'-triphosphate [dGTP] triphosphohydrolase [dGTPase]; gene, Dgt) that establishes the normal dGTP level required for accurate DNA replication but also plays a role in protecting against bacteriophage T7 infection by limiting the dGTP required for viral DNA replication. T7 counteracts Dgt using an inhibitor, the gene product (Gp1.2). This interaction is a useful model system for studying the ongoing evolutionary virus/host "arms race." We determined the structure of Gp1.2 by NMR spectroscopy and solved high-resolution cryo-electron microscopy structures of the Dgt-Gp1.2 complex also including either dGTP substrate or GTP coinhibitor bound in the active site. These structures reveal the mechanism by which Gp1.2 inhibits Dgt and indicate that Gp1.2 preferentially binds the GTP-bound form of Dgt. Biochemical assays reveal that the two inhibitors use different modes of inhibition and bind to Dgt in combination to yield enhanced inhibition. We thus propose an in vivo inhibition model wherein the Dgt-Gp1.2 complex equilibrates with GTP to fully inactivate Dgt, limiting dGTP hydrolysis and preserving the dGTP pool for viral DNA replication.
名称: Inhibitor of dGTPase / タイプ: protein_or_peptide / ID: 2 詳細: The additional N-terminal sequence is retained after cleavage of the expression tag with TEV protease. コピー数: 6 / 光学異性体: LEVO
source_name: PDB, initial_model_type: experimental model
詳細
E. coli dGTPase crystal structure (PDB ID: 4XDS) and T7 bacteriophage NMR structure (PDB ID: 2MDP) models were fit into the EM map using Chimera for subsequent building. After an initial round of real-space refinement, the Gp1.2 N-terminus was re-built into the density using Coot.
精密化
空間: REAL / プロトコル: RIGID BODY FIT
得られたモデル
PDB-7u65: Structure of E. coli dGTPase bound to T7 bacteriophage protein Gp1.2