8YBR | pdb_00008ybr

Choline transporter BetT

• PDB DOI: https://doi.org/10.2210/pdb8YBR/pdb
• EM Map EMD-39122: EMDB EMDataResource

• Classification: CHOLINE-BINDING PROTEIN
• Organism(s): Pseudomonas syringae
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2024-02-16 Released: 2024-09-04 
• Deposition Author(s): Yang, T.J., Nian, Y.W., Lin, H.J., Li, J., Zhang, J.R., Fan, M.R.
• Funding Organization(s): Chinese Academy of Sciences

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 2.57 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Structure and mechanism of the osmoregulated choline transporter BetT.

Yang, T., Nian, Y., Lin, H., Li, J., Lin, X., Li, T., Wang, R., Wang, L., Beattie, G.A., Zhang, J., Fan, M.

(2024) Sci Adv 10: eado6229-eado6229

• PubMed: 39141726 
• DOI: https://doi.org/10.1126/sciadv.ado6229
• Primary Citation Related Structures: 
  8YBQ, 8YBR


• PubMed Abstract: 
  

  The choline-glycine betaine pathway plays an important role in bacterial survival in hyperosmotic environments. Osmotic activation of the choline transporter BetT promotes the uptake of external choline for synthesizing the osmoprotective glycine betaine. Here, we report the cryo-electron microscopy structures of Pseudomonas syringae BetT in the apo and choline-bound states. Our structure shows that BetT forms a domain-swapped trimer with the C-terminal domain (CTD) of one protomer interacting with the transmembrane domain (TMD) of a neighboring protomer. The substrate choline is bound within a tryptophan prism at the central part of TMD. Together with functional characterization, our results suggest that in Pseudomonas species, including the plant pathogen P. syringae and the human pathogen Pseudomonas aeruginosa , BetT is locked at a low-activity state through CTD-mediated autoinhibition in the absence of osmotic stress, and its hyperosmotic activation involves the release of this autoinhibition.

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Organizational Affiliation: 
• CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
University of Chinese Academy of Sciences, Beijing 101408, China.
School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai 200438, China.
Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, IA 50011, USA.
Key Laboratory of Plant Carbon Capture, Chinese Academy of Sciences, Shanghai 200032, China.

Biological Assembly 1  

Global Symmetry: Cyclic - C3  (Explore in 3D)
Global Stoichiometry: Homo 3-mer - A3 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 225.76 kDa 
• Atom Count: 15,150 
• Modeled Residue Count: 1,941 
• Deposited Residue Count: 2,055 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
BCCT family transporter	A, B, C	685	Pseudomonas syringae	Mutation(s): 0  Gene Names: EIZ61_06110

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 2.57 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: 2024-09-04 
Deposition Author(s): Yang, T.J., Nian, Y.W., Lin, H.J., Li, J., Zhang, J.R., Fan, M.R.

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Funding Organization	Location	Grant Number
Chinese Academy of Sciences	China	XDB0630101

Revision History  

• Version 1.0: 2024-09-04
  Type: Initial release
  
• Version 1.1: 2025-07-02
  Changes: Data collection, Structure summary