7SGR
Structure of hemolysin A secretion system HlyB/D complex
Summary for 7SGR
| Entry DOI | 10.2210/pdb7sgr/pdb |
| EMDB information | 25116 |
| Descriptor | Alpha-hemolysin translocation ATP-binding protein HlyB, Membrane fusion protein (MFP) family protein,Hemolysin secretion protein D, chromosomal, [(2~{R})-1-[2-azanylethoxy(oxidanyl)phosphoryl]oxy-3-hexadecanoyloxy-propan-2-yl] (~{Z})-octadec-9-enoate (3 entities in total) |
| Functional Keywords | hydrolase, transport, membrane protein |
| Biological source | Escherichia coli CFT073 More |
| Total number of polymer chains | 12 |
| Total formula weight | 748788.17 |
| Authors | |
| Primary citation | Zhao, H.,Lee, J.,Chen, J. The hemolysin A secretion system is a multi-engine pump containing three ABC transporters. Cell, 185:3329-3340.e13, 2022 Cited by PubMed Abstract: 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. PubMed: 36055198DOI: 10.1016/j.cell.2022.07.017 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (2.9 Å) |
Structure validation
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