Biological Assembly 1  

Global Symmetry: Dihedral - D6  (3D View)
Global Stoichiometry: Homo 24-mer - A24 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: light scattering, electron microscopy

Macromolecule Content

• Total Structure Weight: 1,249.66 kDa 
• Atom Count: 81,522 
• Modelled Residue Count: 10,440 
• Deposited Residue Count: 11,256 
• Unique protein chains: 1

 7W85

Structural of the filamentous Escherichia coli glutamine synthetase

• PDB DOI:  https://doi.org/10.2210/pdb7W85/pdb
• EM Map EMD-32352: EMDB EMDataResource

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


• Deposited: 2021-12-07 Released: 2022-04-06 
• Deposition Author(s): Huang, P.-C., Chen, S.-K., Wu, K.-P.
• Funding Organization(s): Ministry of Science and Technology (MoST, Taiwan), Academia Sinica (Taiwan)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 2.94 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Structural basis for the helical filament formation of Escherichia coli glutamine synthetase.

Huang, P.C., Chen, S.K., Chiang, W.H., Ho, M.R., Wu, K.P.

(2022) Protein Sci 31: e4304-e4304

• PubMed: 35481643 
• DOI: https://doi.org/10.1002/pro.4304
• Primary Citation of Related Structures:  
  7W85


• PubMed Abstract: 
  

Escherichia coli glutamine synthetase (EcGS) spontaneously forms a dodecamer that catalytically converts glutamate to glutamine. EcGS stacks with other dodecamers to create a filament-like polymer visible under transmission electron microscopy. Filamentous EcGS is induced by environmental metal ions. We used cryo-electron microscopy (cryo-EM) to decipher the structure of metal ion (nickel)-induced EcGS helical filament at a sub-3Å resolution. EcGS filament formation involves stacking of native dodecamers by chelating nickel ions to residues His5 and His13 in the first N-terminal helix (H1). His5 and His13 from paired parallel H1 helices provide salt bridges and hydrogen bonds to tightly stack two dodecamers. One subunit of the EcGS filament hosts two nickel ions, whereas the dodecameric interface and the ATP/Mg-binding site both host a nickel ion each. We reveal that upon adding glutamate or ATP for catalytic reactions, nickel-induced EcGS filament reverts to individual dodecamers. Such tunable filament formation is often associated with stress responses. Our results provide detailed structural information on the mechanism underlying reversible and tunable EcGS filament formation.

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Organizational Affiliation: 

Institute of Biochemical Science, College of Life Science, National Taiwan University, Taipei, Taiwan.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Glutamine synthetase	A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T [auth U], U [auth V], V [auth W], W [auth X], X [auth Y]	469	Escherichia coli BL21(DE3)	Mutation(s): 0  Gene Names: glnA, b3870, JW3841 EC: 6.3.1.2
UniProt
Find proteins for P0A9C5 (Escherichia coli (strain K12)) Explore P0A9C5  Go to UniProtKB:  P0A9C5

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NI (Subject of Investigation/LOI)	AA [auth B], AB [auth Q], BA [auth B], BB [auth R], CA [auth C], CB [auth S], DA [auth C], DB [auth S], EA [auth D], EB [auth U], FA [auth D], FB [auth U], GA [auth E], GB [auth V], HA [auth E], HB [auth V], IA [auth F], IB [auth W], JA [auth F], JB [auth W], KA [auth G], KB [auth X], LA [auth G], LB [auth X], MA [auth H], MB [auth Y], NA [auth H], NB [auth Y], OA [auth I], PA [auth I], QA [auth J], RA [auth J], SA [auth K], TA [auth K], UA [auth L], VA [auth L], WA [auth M], XA [auth N], Y [auth A], YA [auth O], Z [auth A], ZA [auth P]	NICKEL (II) ION Ni VEQPNABPJHWNSG-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 2.94 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	Coot	0.9.5
MODEL REFINEMENT	PHENIX	1.18
RECONSTRUCTION	cryoSPARC	3.2

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2022-04-06 
Deposition Author(s): Huang, P.-C., Chen, S.-K., Wu, K.-P.

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Funding Organization	Location	Grant Number
Ministry of Science and Technology (MoST, Taiwan)	Taiwan	--
Academia Sinica (Taiwan)	Taiwan	--

Revision History  

• Version 1.0: 2022-04-06
  Type: Initial release
  
• Version 1.1: 2022-04-20
  Changes: Database references
• Version 1.2: 2022-05-11
  Changes: Database references
• Version 1.3: 2022-06-15
  Changes: Database references