ジャーナル: Structure / 年: 2026 タイトル: Cryo-EM structure of YfdQ reveals a widespread family of bacteriophage-associated proteins with shell-like assemblies. 著者: Davi Gabriel Salustiano Merighi / Guilherme Camargo Pompeu / Gabriel Guarany de Araujo / Anacleto Silva de Souza / Germán Gustavo Sgro / Chuck Shaker Farah / Cristiane Rodrigues Guzzo / 要旨: Bacteriophages are key players in microbial ecosystems with strong biotechnological potential, yet many phage-encoded proteins remain uncharacterized. We present the structure of the YfdQ complex ...Bacteriophages are key players in microbial ecosystems with strong biotechnological potential, yet many phage-encoded proteins remain uncharacterized. We present the structure of the YfdQ complex from the Xanthomonas citri ΦXacm4-11 phage, a conserved DUF2303 protein encoded by double-stranded DNA bacteriophages of the Caudoviricetes class. Using cryo-electron microscopy, we report that native YfdQ assembles into a shell-like structure with D18 symmetry forming a ∼1.1 MegaDalton complex, a hollow interior and a unique equatorial β strand stitching oligomerization interface that holds together the two hemispheres. YfdQ homologs are widely distributed among phages infecting diverse bacterial hosts, suggesting a conserved biological role. YfdQ are found in prophages and cryptic phages. Our results suggest that heterologous expression of YfdQ in X. citri and in Escherichia coli allows the obtention of structurally heterogeneous YfdQ complexes, suggesting that its proper assembly into the shell-like structure may depend on still unidentified viral factors.
履歴
登録
2025年4月15日
登録サイト: RCSB / 処理サイト: RCSB
改定 1.0
2026年7月8日
Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: EM metadata / Data content type: EM metadata / Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: FSC / Data content type: FSC / Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: Half map / Part number: 1 / Data content type: Half map / Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: Half map / Part number: 2 / Data content type: Half map / Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: Image / Data content type: Image / Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: Mask / Part number: 1 / Data content type: Mask / Provider: repository / タイプ: Initial release
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2026年7月8日
Data content type: Primary map / Data content type: Primary map / Provider: repository / タイプ: Initial release
C: YfdQ Protein D: YfdQ Protein E: YfdQ Protein F: YfdQ Protein G: YfdQ Protein H: YfdQ Protein I: YfdQ Protein J: YfdQ Protein K: YfdQ Protein L: YfdQ Protein M: YfdQ Protein N: YfdQ Protein O: YfdQ Protein P: YfdQ Protein Q: YfdQ Protein R: YfdQ Protein S: YfdQ Protein T: YfdQ Protein U: YfdQ Protein V: YfdQ Protein W: YfdQ Protein X: YfdQ Protein Y: YfdQ Protein Z: YfdQ Protein a: YfdQ Protein b: YfdQ Protein c: YfdQ Protein d: YfdQ Protein e: YfdQ Protein f: YfdQ Protein g: YfdQ Protein h: YfdQ Protein i: YfdQ Protein j: YfdQ Protein k: YfdQ Protein l: YfdQ Protein
中空か: NO / エンベロープを持つか: NO / 単離: OTHER / タイプ: VIRION
天然宿主
生物種: Xanthomonas citri pv. citri str. 306 / 株: 306
緩衝液
pH: 7.5 詳細: 50 mM Tris-HCl, 100 mM NaCl, 10 mM MgSO47(H2O), pH 7.5
試料
包埋: NO / シャドウイング: NO / 染色: NO / 凍結: YES 詳細: native particles produced during phiXacm4-11 infection
急速凍結
凍結剤: ETHANE / 湿度: 100 % / 凍結前の試料温度: 295 K 詳細: A purified YfdQ proteins were pipetted over Glow-Discharged Quantifoil CU-R2/2 400 Mesh grids with a 2 nm ultrathin carbon layer and vitrified by plunge-freezing using a Vitrobot (Thermo ...詳細: A purified YfdQ proteins were pipetted over Glow-Discharged Quantifoil CU-R2/2 400 Mesh grids with a 2 nm ultrathin carbon layer and vitrified by plunge-freezing using a Vitrobot (Thermo Fisher Scientific). The sample was drained by 3.5 s blot and 0 force, and 4.5 s and 0 force programs.
電子線照射量: 44.89 e/Å2 / 検出モード: COUNTING フィルム・検出器のモデル: FEI FALCON III (4k x 4k) 詳細: Data were acquired using a Titan Krios G3i cryo-electron microscope, 300 kV (Thermo Fisher Scientific), at the LNNano facility, CNPEM, Campinas, Brazil. The microscope was equipped with a 4k- ...詳細: Data were acquired using a Titan Krios G3i cryo-electron microscope, 300 kV (Thermo Fisher Scientific), at the LNNano facility, CNPEM, Campinas, Brazil. The microscope was equipped with a 4k-4k CMOS camera, phase plate, spherical aberration corrector, and Falcon 3 detector without energy filter or a K3 detector with energy filter. For the native YfdQ dataset, data collection utilized the Falcon 3 detector in counting mode.
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解析
EMソフトウェア
ID
名称
カテゴリ
2
EPU
画像取得
4
cryoSPARC
CTF補正
7
UCSF ChimeraX
モデルフィッティング
9
Coot
モデル精密化
画像処理
詳細: Using CryoSPARC, patch motion correction and patch CTF estimation jobs were run before using a combination of Blob Picker and Template Picker in micrograph subsets to obtain a stack of ...詳細: Using CryoSPARC, patch motion correction and patch CTF estimation jobs were run before using a combination of Blob Picker and Template Picker in micrograph subsets to obtain a stack of 369,017 particles after extraction in 460-460 pixel boxes. Rounds of 2D classification were used to select the particles that contributed to the best resolved classes. The chosen 249,600 particles were used to reconstruct an ab Initio model using D18 symmetry inferred from the 2D classes (C1 did not produce shell-like models). Homogeneous refinement using this volume as input and maintaining the symmetry yielded an interpretable model at 3.85 A resolution. To assess possible heterogeneities, a 3D classification job was run (C1 symmetry, 10 classes), but no other shell configurations could be observed. A non-uniform refinement with applied D18 symmetry of the 237,960 particles from the largest class yielded the final 3.44 A resolution map.
CTF補正
タイプ: PHASE FLIPPING AND AMPLITUDE CORRECTION
対称性
点対称性: D18 (2回x18回 2面回転対称)
3次元再構成
解像度: 3.9 Å / 解像度の算出法: FSC 0.143 CUT-OFF / 粒子像の数: 237960 / 対称性のタイプ: POINT
原子モデル構築
プロトコル: RIGID BODY FIT / 空間: REAL
精密化
最高解像度: 3.9 Å 立体化学のターゲット値: REAL-SPACE (WEIGHTED MAP SUM AT ATOM CENTERS)