8ZOR | pdb_00008zor

Cryo-EM structure of bicarbonate transporter SbtA in complex with PII-like signaling protein SbtB (T-loop truncation) from Synechocystis sp. PCC 6803

• PDB DOI: https://doi.org/10.2210/pdb8ZOR/pdb
• EM Map EMD-60316: EMDB EMDataResource

• Classification: TRANSPORT PROTEIN
• Organism(s): Synechocystis, Synechocystis sp. PCC 6803 substr. Kazusa
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2024-05-29 Released: 2025-12-03 
• Deposition Author(s): Hou, W.T., Zhou, C.Z.
• Funding Organization(s): Chinese Academy of Sciences

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.10 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Cryo-EM structure of bicarbonate transporter SbtA in complex with PII-like signaling protein SbtB T-loop truncation from Synechocystis sp. PCC 6803

Hou, W.T., Zhou, C.Z.

To be published.

Biological Assembly 1  

Global Symmetry: Cyclic - C3  (Explore in 3D)
Global Stoichiometry: Hetero 6-mer - A3B3 

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

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 155.26 kDa 
• Atom Count: 9,426 
• Modeled Residue Count: 1,263 
• Deposited Residue Count: 1,452 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Slr1512 protein	A, C, E [auth G]	374	Synechocystis	Mutation(s): 0  Gene Names: slr1512
UniProt
Find proteins for P73953 (Synechocystis sp. (strain ATCC 27184 / PCC 6803 / Kazusa)) Explore P73953  Go to UniProtKB:  P73953

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Membrane-associated protein slr1513	B [auth D], D [auth E], F [auth H]	110	Synechocystis sp. PCC 6803 substr. Kazusa	Mutation(s): 0  Gene Names: slr1513
UniProt
Find proteins for P73954 (Synechocystis sp. (strain ATCC 27184 / PCC 6803 / Kazusa)) Explore P73954  Go to UniProtKB:  P73954

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
BCT (Subject of Investigation/LOI)	G [auth A], H [auth C], I [auth G]	BICARBONATE ION C H O3 BVKZGUZCCUSVTD-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.10 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2025-12-03 
Deposition Author(s): Hou, W.T., Zhou, C.Z.

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Funding Organization	Location	Grant Number
Chinese Academy of Sciences	China	XDB37020301
Chinese Academy of Sciences	China	XDA24020302

Revision History  

• Version 1.0: 2025-12-03
  Type: Initial release