+検索条件
-Structure paper
タイトル | The hemolysin A secretion system is a multi-engine pump containing three ABC transporters. |
---|---|
ジャーナル・号・ページ | Cell, Vol. 185, Issue 18, Page 3329-3340.e13, Year 2022 |
掲載日 | 2022年9月1日 |
著者 | Hongtu Zhao / James Lee / Jue Chen / |
PubMed 要旨 | Type 1 secretion systems (T1SSs) are widespread in pathogenic Gram-negative bacteria, extruding protein substrates following synthesis of the entire polypeptide. The Escherichia coli hemolysin A ...Type 1 secretion systems (T1SSs) are widespread in pathogenic Gram-negative bacteria, extruding protein substrates following synthesis of the entire polypeptide. The Escherichia coli hemolysin A secretion system has long been considered a prototype in structural and mechanistic studies of T1SSs. Three membrane proteins-an inner membrane ABC transporter HlyB, an adaptor protein HlyD, and an outer membrane porin TolC-are required for secretion. However, the stoichiometry and structure of the complex are unknown. Here, cryo-electron microscopy (cryo-EM) structures determined in two conformations reveal that the inner membrane complex is a hetero-dodecameric assembly comprising three HlyB homodimers and six HlyD subunits. Functional studies indicate that oligomerization of HlyB and HlyD is essential for protein secretion and that polypeptides translocate through a canonical ABC transporter pathway in HlyB. Our data suggest that T1SSs entail three ABC transporters, one that functions as a protein channel and two that allosterically power the translocation process. |
リンク | Cell / PubMed:36055198 |
手法 | EM (単粒子) |
解像度 | 2.9 - 3.4 Å |
構造データ | EMDB-25116, PDB-7sgr: EMDB-27326, PDB-8dck: |
化合物 | ChemComp-6OU: ChemComp-ATP: ChemComp-MG: |
由来 |
|
キーワード | MEMBRANE PROTEIN / hydrolase / transport |