6YG8

Cryo-EM structure of a BcsB pentamer in the context of an assembled Bcs macrocomplex

• PDB DOI: https://doi.org/10.2210/pdb6YG8/pdb
• EM Map EMD-10799: EMDB EMDataResource

• Classification: SIGNALING PROTEIN
• Organism(s): Escherichia coli
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2020-03-27 Released: 2021-02-24 
• Deposition Author(s): Zouhir, S., Krasteva, P.V.
• Funding Organization(s): ATIP-Avenir, European Research Council (ERC), Centre National de la Recherche Scientifique (CNRS), Institute for Integrative Biology of the Cell (I2BC), European Institute of Chemistry and Biology (IECB)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.00 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Architecture and regulation of an enterobacterial cellulose secretion system.

Abidi, W., Zouhir, S., Caleechurn, M., Roche, S., Krasteva, P.V.

(2021) Sci Adv 7

• PubMed: 33563593 
• DOI: https://doi.org/10.1126/sciadv.abd8049
• Primary Citation of Related Structures:  
  6YAR, 6YAY, 6YB3, 6YB5, 6YBB, 6YBU, 6YG8


• PubMed Abstract: 
  

  Many free-living and pathogenic enterobacteria secrete biofilm-promoting cellulose using a multicomponent, envelope-embedded Bcs secretion system under the control of intracellular second messenger c-di-GMP. The molecular understanding of system assembly and cellulose secretion has been largely limited to the crystallographic studies of a distantly homologous BcsAB synthase tandem and a low-resolution reconstruction of an assembled macrocomplex that encompasses most of the inner membrane and cytosolic subunits and features an atypical layered architecture. Here, we present cryo-EM structures of the assembled Bcs macrocomplex, as well as multiple crystallographic snapshots of regulatory Bcs subcomplexes. The structural and functional data uncover the mechanism of asymmetric secretion system assembly and periplasmic crown polymerization and reveal unexpected subunit stoichiometry, multisite c-di-GMP recognition, and ATP-dependent regulation.

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Organizational Affiliation: 

Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91198 Gif- sur-Yvette, France.

Biological Assembly 1  

Global Symmetry: Helical - H  (Explore in 3D)
Global Stoichiometry: Homo 5-mer - A5 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: microscopy

Macromolecule Content

• Total Structure Weight: 430.92 kDa 
• Atom Count: 24,330 
• Modelled Residue Count: 3,132 
• Deposited Residue Count: 3,895 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Bacterial cellulose secretion regulator BcsB	A, B, C, D, E	779	Escherichia coli	Mutation(s): 0  Gene Names:  bcsB, A8C65_00280, AC789_1c39010, ACU57_05345, AM464_10380, BHS81_21120, BK292_24560, BON72_13325, BON75_10020, BON76_21165, BON94_21155, BZL31_14275, C5P01_24165, C9162_26260, CI641_010915, CWS33_18410, D3O91_11715, D9I18_15765, DQF57_09480, E0J34_09745, E0K84_22715, E2127_16410, E2128_18000, E2129_18135, E2134_17800, E5P22_13645, ELV08_08610, F1E03_18495, F1E19_10130, FRV13_18850
UniProt
Find proteins for P37652 (Escherichia coli (strain K12)) Explore P37652  Go to UniProtKB:  P37652

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.00 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
RECONSTRUCTION	cryoSPARC	v2
MODEL REFINEMENT	PHENIX	1.16-3549-000

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2021-02-24 
Deposition Author(s): Zouhir, S., Krasteva, P.V.

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Funding Organization	Location	Grant Number
ATIP-Avenir		--
European Research Council (ERC)		BioMatrix, ERC StG #757507
Centre National de la Recherche Scientifique (CNRS)		--
Institute for Integrative Biology of the Cell (I2BC)		--
European Institute of Chemistry and Biology (IECB)		--

Revision History  

• Version 1.0: 2021-02-24
  Type: Initial release