11AM | pdb_000011am

Cryo-EM structure of a bovine CLC-K S68N/R355K chloride channel with 100 mM Ca2+

• PDB DOI: https://doi.org/10.2210/pdb11AM/pdb
• EM Map EMD-75590: EMDB EMDataResource

• Classification: TRANSPORT PROTEIN
• Organism(s): Bos taurus
• Expression System: Homo sapiens
• Mutation(s): Yes 


• Deposited: 2026-02-13 Released: 2026-09-09 
• Deposition Author(s): Chien, C.-T., Chiu, W., Maduke, M.
• Funding Organization(s): National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Disease (NIH/NIDDK), National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.40 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Mechanism of gating and isoform-specific inhibition in renal CLC chloride channels

Chien, C.T., Sobecks-Doherty, B.L., Powers, A.S., Das, A., Kreiter, J., Barry, C.N., Chen, M., Hinman, A., Petrakian, C.F., Williams, B., Wood, C.A.P., Xu, M., Dror, R.O., Chiu, W., Maduke, M.

(2026) Proc Natl Acad Sci U S A 123

• DOI: https://doi.org/10.1073/pnas.2605886123

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

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

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 147.11 kDa 
• Atom Count: 9,590 
• Modeled Residue Count: 1,242 
• Deposited Residue Count: 1,342 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Chloride voltage-gated channel Ka	A, B	671	Bos taurus	Mutation(s): 3  Gene Names: CLCNKA
UniProt
Find proteins for E1B792 (Bos taurus) Explore E1B792  Go to UniProtKB:  E1B792

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CL	C [auth A], D [auth B]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.40 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX	1.21.1_5286
RECONSTRUCTION	cryoSPARC

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-09-09 
Deposition Author(s): Chien, C.-T., Chiu, W., Maduke, M.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Disease (NIH/NIDDK)	United States	R01DK128881
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R01GM150905

Revision History  

• Version 1.0: 2026-09-09
  Type: Initial release