National Natural Science Foundation of China (NSFC)
31570841
中国
引用
ジャーナル: Sci Adv / 年: 2021 タイトル: Identification and architecture of a putative secretion tube across mycobacterial outer envelope. 著者: Xiaoying Cai / Lei Liu / Chunhong Qiu / Chongzheng Wen / Yao He / Yanxiang Cui / Siyu Li / Xuan Zhang / Longhua Zhang / Changlin Tian / Lijun Bi / Z Hong Zhou / Weimin Gong / 要旨: Tuberculosis-causing mycobacteria have thick cell-wall and capsule layers that are formed from complex structures. Protein secretion across these barriers depends on a specialized protein secretion ...Tuberculosis-causing mycobacteria have thick cell-wall and capsule layers that are formed from complex structures. Protein secretion across these barriers depends on a specialized protein secretion system, but none has been reported. We show that Rv3705c and its homologous MSMEG_6251 in are tube-forming proteins in the mycobacterial envelope (TiME). Crystallographic and cryo-EM structures of these two proteins show that both proteins form rotationally symmetric rings. Two layers of TiME rings pack together in a tail-to-tail manner into a ring-shaped complex, which, in turn, stacks together to form tubes. TiME was detected mainly in the cell wall and capsule. Knocking out the TiME gene markedly decreased the amount of secreted protein in the culture medium, and expression of this gene in knocked-out strain partially restored the level of secreted protein. Our structure and functional data thus suggest that TiME forms a protein transport tube across the mycobacterial outer envelope.
A: Tube-forming protein in Mycobacterial Envelope (TiME) B: Tube-forming protein in Mycobacterial Envelope (TiME) C: Tube-forming protein in Mycobacterial Envelope (TiME) D: Tube-forming protein in Mycobacterial Envelope (TiME) E: Tube-forming protein in Mycobacterial Envelope (TiME) F: Tube-forming protein in Mycobacterial Envelope (TiME) G: Tube-forming protein in Mycobacterial Envelope (TiME) ヘテロ分子
解像度: 3.3→49.78 Å / Cor.coef. Fo:Fc: 0.873 / Cor.coef. Fo:Fc free: 0.874 / SU B: 13.338 / SU ML: 0.213 / 交差検証法: THROUGHOUT / σ(F): 0 / ESU R: 0.512 / ESU R Free: 0.319 / 立体化学のターゲット値: MAXIMUM LIKELIHOOD 詳細: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS U VALUES : REFINED INDIVIDUALLY
Rfactor
反射数
%反射
Selection details
Rfree
0.2352
3242
5.1 %
RANDOM
Rwork
0.2225
-
-
-
obs
0.2231
60716
99.79 %
-
溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK