National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)
R03 AI135767
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01 GM098621
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01 GM116942
米国
引用
ジャーナル: Cell Rep / 年: 2021 タイトル: The structural basis of Salmonella AB toxin neutralization by antibodies targeting the glycan-receptor binding subunits. 著者: Tri Nguyen / Angelene F Richards / Durga P Neupane / J Ryan Feathers / Yi-An Yang / Ji Hyun Sim / Haewon Byun / Sohyoung Lee / Changhwan Ahn / Greta Van Slyke / J Christopher Fromme / ...著者: Tri Nguyen / Angelene F Richards / Durga P Neupane / J Ryan Feathers / Yi-An Yang / Ji Hyun Sim / Haewon Byun / Sohyoung Lee / Changhwan Ahn / Greta Van Slyke / J Christopher Fromme / Nicholas J Mantis / Jeongmin Song / 要旨: Many bacterial pathogens secrete AB toxins comprising two functionally distinct yet complementary "A" and "B" subunits to benefit the pathogens during infection. The lectin-like pentameric B subunits ...Many bacterial pathogens secrete AB toxins comprising two functionally distinct yet complementary "A" and "B" subunits to benefit the pathogens during infection. The lectin-like pentameric B subunits recognize specific sets of host glycans to deliver the toxin into target host cells. Here, we offer the molecular mechanism by which neutralizing antibodies, which have the potential to bind to all glycan-receptor binding sites and thus completely inhibit toxin binding to host cells, are inhibited from exerting this action. Cryogenic electron microscopy (cryo-EM)-based analyses indicate that the skewed positioning of the toxin A subunit(s) toward one side of the toxin B pentamer inhibited neutralizing antibody binding to the laterally located epitopes, rendering some glycan-receptor binding sites that remained available for the toxin binding and endocytosis process, which is strikingly different from the counterpart antibodies recognizing the far side-located epitopes. These results highlight additional features of the toxin-antibody interactions and offer important insights into anti-toxin strategies.
濃度: 0.2 mg/ml / 包埋: NO / シャドウイング: NO / 染色: NO / 凍結: YES 詳細: Freshly prepared size-exclusion-chromatography purified complex between Fab fragment of TyTx4 and Typhoid toxin wild-type
モード: BRIGHT FIELD / 倍率(公称値): 49000 X / 最大 デフォーカス(公称値): 1500 nm / 最小 デフォーカス(公称値): 800 nm / Cs: 2.7 mm / C2レンズ絞り径: 50 µm
試料ホルダ
凍結剤: NITROGEN
撮影
電子線照射量: 51.5 e/Å2 / フィルム・検出器のモデル: GATAN K3 (6k x 4k)
電子光学装置
エネルギーフィルター名称: GIF Bioquantum / エネルギーフィルタースリット幅: 20 eV
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解析
EMソフトウェア
ID
名称
バージョン
カテゴリ
1
RELION
3
粒子像選択
2
SerialEM
画像取得
4
Gctf
CTF補正
7
Coot
0.8.9.1
モデルフィッティング
9
PHENIX
1.16-3549
モデル精密化
13
RELION
3.1
3次元再構成
CTF補正
タイプ: PHASE FLIPPING AND AMPLITUDE CORRECTION
対称性
点対称性: C5 (5回回転対称)
3次元再構成
解像度: 3.13 Å / 解像度の算出法: FSC 0.143 CUT-OFF / 粒子像の数: 97594 / 対称性のタイプ: POINT
原子モデル構築
詳細: Initial local fitting was done using Chimera and then Coot was used for rebuilding Fab variable domains into correct sequences. Refinement was performed using Real Space Refine in PHENIX and ...詳細: Initial local fitting was done using Chimera and then Coot was used for rebuilding Fab variable domains into correct sequences. Refinement was performed using Real Space Refine in PHENIX and was iterated with manual building in Coot.