9SKX | pdb_00009skx

Cryo-EM structure of H. neapolitanus CsoSCA C283A/C284A inactive mutant, hexamer

• PDB DOI: https://doi.org/10.2210/pdb9SKX/pdb
• EM Map EMD-54978: EMDB EMDataResource

• Classification: LYASE
• Organism(s): Escherichia coli K-12, Halothiobacillus neapolitanus c2
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 2025-09-02 Released: 2026-04-22 
• Deposition Author(s): Gaullier, G., Vogiatzi, N., Blikstad, C.
• Funding Organization(s): Swedish Research Council, Formas, a Swedish research council for sustainable development

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 2.08 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Starting Model: in silico

Literature

Molecular mechanism of redox regulation of the alpha-carboxysomal carbonic anhydrase CsoSCA

Vogiatzi, N., Gaullier, G., Leufstadius, J., Andersson, T., Scherbauer, T., Blikstad, C.

(2026) bioRxiv 

• DOI: https://doi.org/10.64898/2026.04.02.716132

Biological Assembly 1  

Global Symmetry: Dihedral - D3  (Explore in 3D)
Global Stoichiometry: Homo 6-mer - A6 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 204.09 kDa 
• Atom Count: 7,652 
• Modeled Residue Count: 942 
• Deposited Residue Count: 1,838 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Maltose/maltodextrin-binding periplasmic protein,Carboxysome shell carbonic anhydrase	A, B	919	Escherichia coli K-12, Halothiobacillus neapolitanus c2 This entity is chimeric	Mutation(s): 2  Gene Names: malE, b4034, JW3994, csoS3, ORF1, Hneap_0919 EC: 4.2.1.1
UniProt
Find proteins for O85042 (Halothiobacillus neapolitanus (strain ATCC 23641 / DSM 15147 / CIP 104769 / NCIMB 8539 / c2)) Explore O85042  Go to UniProtKB:  O85042
Find proteins for P0AEX9 (Escherichia coli (strain K12)) Explore P0AEX9  Go to UniProtKB:  P0AEX9
UniProt Groups	O85042P0AEX9

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN (Subject of Investigation/LOI)	C [auth A], D [auth B]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 2.08 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	Servalcat	0.4.99
RECONSTRUCTION	cryoSPARC	4.7

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-04-22 
Deposition Author(s): Gaullier, G., Vogiatzi, N., Blikstad, C.

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Funding Organization	Location	Grant Number
Swedish Research Council	Sweden	2019-03700_VR
Formas, a Swedish research council for sustainable development	Sweden	2019-01171_Formas
Swedish Research Council	Sweden	2023-05296_VR

Revision History  

• Version 1.0: 2026-04-22
  Type: Initial release