7ZZY | pdb_00007zzy

Solution BcsD structure

• PDB DOI: https://doi.org/10.2210/pdb7ZZY/pdb
• EM Map EMD-15041: EMDB EMDataResource

• Classification: STRUCTURAL PROTEIN
• Organism(s): Novacetimonas hansenii ATCC 23769
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2022-05-26 Released: 2022-12-28 
• Deposition Author(s): Krasteva, P.V., Abidi, W., Decossas, M.
• Funding Organization(s): European Research Council (ERC)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.30 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Bacterial crystalline cellulose secretion via a supramolecular BcsHD scaffold.

Abidi, W., Decossas, M., Torres-Sanchez, L., Puygrenier, L., Letoffe, S., Ghigo, J.M., Krasteva, P.V.

(2022) Sci Adv 8: eadd1170-eadd1170

• PubMed: 36525496 
• DOI: https://doi.org/10.1126/sciadv.add1170
• Primary Citation Related Structures: 
  7ZZQ, 7ZZY


• PubMed Abstract: 
  

  Cellulose, the most abundant biopolymer on Earth, is not only the predominant constituent of plants but also a key extracellular polysaccharide in the biofilms of many bacterial species. Depending on the producers, chemical modifications, and three-dimensional assemblies, bacterial cellulose (BC) can present diverse degrees of crystallinity. Highly ordered, or crystalline, cellulose presents great economical relevance due to its ever-growing number of biotechnological applications. Even if some acetic acid bacteria have long been identified as BC superproducers, the molecular mechanisms determining the secretion of crystalline versus amorphous cellulose remain largely unknown. Here, we present structural and mechanistic insights into the role of the accessory subunits BcsH (CcpAx) and BcsD (CesD) that determine crystalline BC secretion in the Gluconacetobacter lineage. We show that oligomeric BcsH drives the assembly of BcsD into a supramolecular cytoskeletal scaffold that likely stabilizes the cellulose-extruding synthase nanoarrays through an unexpected inside-out mechanism for secretion system assembly.

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Organizational Affiliation: 
• Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Pessac, France.
'Structural Biology of Biofilms' Group, European Institute of Chemistry and Biology (IECB), Pessac, France.
Doctoral School of Therapeutic Innovation ITFA, Université Paris-Saclay, Orsay, France.
Institut Pasteur, Université de Paris, UMR CNRS2001, 'Genetics of Biofilms' laboratory, 25-28 rue du Docteur Roux, 75015 Paris, France.

Biological Assembly 1  

Global Symmetry: Dihedral - D4  (Explore in 3D)
Global Stoichiometry: Homo 8-mer - A8 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 164.77 kDa 
• Atom Count: 8,784 
• Modeled Residue Count: 1,104 
• Deposited Residue Count: 1,464 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Cellulose biosynthesis protein	A, B [auth G], C [auth E], D [auth C], E [auth H], F [auth B], G [auth D], H [auth F]	183	Novacetimonas hansenii ATCC 23769	Mutation(s): 0  Gene Names: acsD, GXY_04292
UniProt
Find proteins for Q76KJ6 (Novacetimonas hansenii ATCC 23769) Explore Q76KJ6  Go to UniProtKB:  Q76KJ6

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.30 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX
RECONSTRUCTION	cryoSPARC	3

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2022-12-28 
Deposition Author(s): Krasteva, P.V., Abidi, W., Decossas, M.

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Funding Organization	Location	Grant Number
European Research Council (ERC)	European Union	BioMatrix-ERC-2017-StG

Revision History  

• Version 1.0: 2022-12-28
  Type: Initial release
  
• Version 1.1: 2024-07-24
  Changes: Data collection
• Version 1.2: 2025-07-02
  Changes: Data collection, Structure summary