National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)
75N93022C00035
米国
引用
ジャーナル: bioRxiv / 年: 2024 タイトル: Structural architecture of TolQ-TolR inner membrane protein complex from opportunistic pathogen . 著者: Elina Karimullina / Yirui Guo / Hanif M Khan / Tabitha Emde / Bradley Quade / Rosa Di Leo / Zbyszek Otwinowski / D Tieleman Peter / Dominika Borek / Alexei Savchenko 要旨: Gram-negative bacteria harness the proton motive force (PMF) within their inner membrane (IM) to uphold the integrity of their cell envelope, an indispensable aspect for both division and survival. ...Gram-negative bacteria harness the proton motive force (PMF) within their inner membrane (IM) to uphold the integrity of their cell envelope, an indispensable aspect for both division and survival. The IM TolQ-TolR complex is the essential part of the Tol-Pal system, serving as a conduit for PMF energy transfer to the outer membrane. Here we present cryo-EM reconstructions of TolQ in apo and TolR- bound forms at atomic resolution. The apo TolQ configuration manifests as a symmetric pentameric pore, featuring a trans-membrane funnel leading towards a cytoplasmic chamber. In contrast, the TolQ-TolR complex assumes a proton non-permeable stance, characterized by the TolQ pentamer's flexure to accommodate the TolR dimer, where two protomers undergo a translation-based relationship. Our structure-guided analysis and simulations support the rotor-stator mechanism of action, wherein the rotation of the TolQ pentamer harmonizes with the TolR protomers' interplay. These findings broaden our mechanistic comprehension of molecular stator units empowering critical functions within the Gram-negative bacterial cell envelope. TEASER: Apo TolQ and TolQ-TolR structures depict structural rearrangements required for cell envelope organization in bacterial cell division.
凍結剤: PROPANE / チャンバー内湿度: 100 % / チャンバー内温度: 277 K / 装置: FEI VITROBOT MARK IV
詳細
50mM Tris pH 8.0; 150mM NaCl; 0.5 mM TCEP
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電子顕微鏡法
顕微鏡
FEI TITAN KRIOS
撮影
フィルム・検出器のモデル: GATAN K3 (6k x 4k) / 実像数: 2718 / 平均露光時間: 4.4 sec. / 平均電子線量: 100.0 e/Å2 詳細: Images were collected as movies, with each movie containing 125 frames. The beam-image shift method, utilizing a 3x3 pattern, was used, with one image per grid hole.
Patch motion and patch CTF correction with binning to 0.833 A/pixel.
粒子像選択
選択した数: 472724 詳細: Manual picking to generate templates. Template based autopicking to get 472724 particles. Iterative 2D classification to get 246741 particles.
初期モデル
モデルのタイプ: INSILICO MODEL
最終 再構成
使用したクラス数: 4 / 想定した対称性 - 点群: C5 (5回回転対称) / 解像度のタイプ: BY AUTHOR / 解像度: 3.02 Å / 解像度の算出法: FSC 0.143 CUT-OFF / ソフトウェア - 名称: cryoSPARC 詳細: Map was post processed using DeepEMHancer to guide refinement. The deposited maps are pre-DeepEMHancer 使用した粒子像数: 215170
初期 角度割当
タイプ: MAXIMUM LIKELIHOOD
最終 角度割当
タイプ: MAXIMUM LIKELIHOOD
最終 3次元分類
クラス数: 1
FSC曲線 (解像度の算出)
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原子モデル構築 1
初期モデル
Chain - Source name: SwissModel / Chain - Initial model type: in silico model
得られたモデル
PDB-9avi: TolQ inner membrane protein from Acinetobacter baumannii