EMDB/PDB/SASBDBから引用されている文献のデータベース

キーワード
構造解析手法	All X線回折 NMR 電子顕微鏡小角散乱中性子線回折線維回折粉末回折赤外分光 EPR FRET 理論モデルハイブリッド
著者・登録者
ジャーナル
IF	>30 >20 >10 >5 all

タイトル	In situ structures of the Dot/Icm T4SS identify the DotA-IcmX complex as the gatekeeper for effector translocation.
ジャーナル・号・ページ	Proc Natl Acad Sci U S A, Vol. 122, Issue 39, Page e2516300122, Year 2025
掲載日	2025年9月30日
著者	Jian Yue / Samira Heydari / Donghyun Park / David Chetrit / Shoichi Tachiyama / Wangbiao Guo / Jack M Botting / Shenping Wu / Craig R Roy / Jun Liu /
PubMed 要旨	The Dot/Icm machine of is among the most versatile type IV secretion systems (T4SSs), capable of translocating more than 330 distinct effector proteins across the bacterial envelope into host cells. ...The Dot/Icm machine of is among the most versatile type IV secretion systems (T4SSs), capable of translocating more than 330 distinct effector proteins across the bacterial envelope into host cells. Assembly and function of the system require at least 27 Dot and Icm proteins, yet its architecture and activation mechanism remain poorly understood at the molecular level. Here, we deploy in situ single-particle cryoelectron microscopy to determine near-atomic structures of the Dot/Icm machine and its intimate association with three distinct outer membrane porins in intact bacteria. Notably, two essential yet enigmatic components, DotA and IcmX, form a pentameric protochannel in an inactive state at the central axis of the Dot/Icm machine. Upon Dot/Icm activation with host lysate, this protochannel undergoes extensive rearrangements to generate an extended transenvelope conduit, as visualized by cryoelectron tomography (cryo-ET) and subtomogram averaging. Furthermore, a combination of cryo-ET and cryo-FIB milling of macrophages infected with reveals tethering of the Dot/Icm machine to the host membrane, suggesting direct translocation of effector proteins from the bacterial cytoplasm into the host. Together, our studies identify the DotA-IcmX complex as a gatekeeper for effector translocation and provide a molecular framework for understanding the assembly and activation of the elaborate Dot/Icm T4SS.
リンク	Proc Natl Acad Sci U S A / PubMed:40986344 / PubMed Central
手法	EM (単粒子)
解像度	2.96 - 4.63 Å
構造データ	49393 9ngu EMDB-49393: In-situ cryo-EM structure of outer membrane cap (OMC) of the Dot/Icm machine PDB-9ngu: In situ cryo-EM structure of outer membrane cap (OMC) of the Legionella Dot/Icm T4SS machine 手法: EM (単粒子) / 解像度: 2.96 Å 49394 9ngv EMDB-49394: In-situ cryo-EM structure of periplasmic ring (PR) of the Dot/Icm machine PDB-9ngv: In situ cryo-EM structure of periplasmic ring (PR) of the Legionella Dot/Icm T4SS machine. 手法: EM (単粒子) / 解像度: 3.04 Å 49395 9ngw 9nh2 EMDB-49395: In-situ cryo-EM structure of Dome of the Dot/Icm machine PDB-9ngw: In-situ cryo-EM structure of Dome of the Legionella Dot/Icm machine PDB-9nh2: In situ cryo-EM structure of porin III of the Legionella Dot/Icm T4SS machine 手法: EM (単粒子) / 解像度: 3.08 Å 49396 9ngy EMDB-49396: In-situ cryo-EM structure of protochannel of the Dot/Icm machine PDB-9ngy: In situ cryo-EM structure of protochannel (DotA-IcmX) of the Legionella Dot/Icm T4SS machine 手法: EM (単粒子) / 解像度: 3.63 Å 49398 9nh0 EMDB-49398: In-situ cryo-EM structure of PR and DotA-IcmX of the Dot/Icm machine at C1 PDB-9nh0: In situ cryo-EM structure of PR and DotA-IcmX of the Legionella Dot/Icm T4SS machine at C1 symmetry 手法: EM (単粒子) / 解像度: 4.63 Å 49399 9nh1 EMDB-49399: In-situ cryo-EM structure of porinI of the Dot/Icm machine PDB-9nh1: In situ cryo-EM structure of porin I of the Legionella Dot/Icm T4SS machine 手法: EM (単粒子) / 解像度: 3.56 Å
由来	legionella pneumophila subsp. pneumophila (バクテリア)
キーワード	PROTEIN TRANSPORT / Type IVB Dot/Icm Secretion Machine