7B9S image
Entry Detail
PDB ID:
7B9S
EMDB ID:
Title:
Structure of the mycobacterial ESX-5 Type VII Secretion System hexameric pore complex
Biological Source:
PDB Version:
Deposition Date:
2020-12-14
Release Date:
2021-07-07
Method Details:
Experimental Method:
Resolution:
3.40 Å
Aggregation State:
PARTICLE
Reconstruction Method:
SINGLE PARTICLE
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:EccB5
Chain IDs:E (auth: B), J (auth: A), O (auth: J), T (auth: O), Y (auth: T), DA (auth: 1)
Chain Length:506
Number of Molecules:6
Biological Source:Mycobacterium xenopi RIVM700367
Polymer Type:polypeptide(L)
Description:EccC5
Chain IDs:C, H (auth: F), M (auth: K), R (auth: P), W (auth: V), BA (auth: 2)
Chain Length:1392
Number of Molecules:6
Biological Source:Mycobacterium xenopi RIVM700367
Polymer Type:polypeptide(L)
Description:EccE5
Chain IDs:A (auth: E), F (auth: H), K (auth: M), P (auth: R), U (auth: Y), Z (auth: 4)
Chain Length:400
Number of Molecules:6
Biological Source:Mycobacterium xenopi RIVM700367
Polymer Type:polypeptide(L)
Description:EccD5
Chain IDs:B (auth: X), D, G (auth: I), I (auth: G), L (auth: N), N (auth: L), Q (auth: S), S (auth: Q), V (auth: Z), X (auth: W), AA (auth: 5), CA (auth: 3)
Chain Length:502
Number of Molecules:12
Biological Source:Mycobacterium xenopi RIVM700367
Ligand Molecules
Primary Citation
Structure of the mycobacterial ESX-5 type VII secretion system pore complex.
Sci Adv 7 ? ? (2021)
PMID: 34172453 DOI: 10.1126/sciadv.abg9923

Abstact

The ESX-5 type VII secretion system is a membrane-spanning protein complex key to the virulence of mycobacterial pathogens. However, the overall architecture of the fully assembled translocation machinery and the composition of the central secretion pore have remained unknown. Here, we present the high-resolution structure of the 2.1-megadalton ESX-5 core complex. Our structure captured a dynamic, secretion-competent conformation of the pore within a well-defined transmembrane section, sandwiched between two flexible protein layers at the cytosolic entrance and the periplasmic exit. We propose that this flexibility endows the ESX-5 machinery with large conformational plasticity required to accommodate targeted protein secretion. Compared to known secretion systems, a highly dynamic state of the pore may represent a fundamental principle of bacterial secretion machineries.

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Primary Citation of related structures