6KKU | pdb_00006kku

human KCC1 structure determined in NaCl and GDN


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.50 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report

Validation slider image for 6KKU

This is version 2.2 of the entry. See complete history

Literature

Cryo-EM structures of the human cation-chloride cotransporter KCC1.

Liu, S.Chang, S.Han, B.Xu, L.Zhang, M.Zhao, C.Yang, W.Wang, F.Li, J.Delpire, E.Ye, S.Bai, X.C.Guo, J.

(2019) Science 366: 505-508

  • DOI: https://doi.org/10.1126/science.aay3129
  • Primary Citation Related Structures: 
    6KKR, 6KKT, 6KKU

  • PubMed Abstract: 

    Cation-chloride cotransporters (CCCs) mediate the coupled, electroneutral symport of cations with chloride across the plasma membrane and are vital for cell volume regulation, salt reabsorption in the kidney, and γ-aminobutyric acid (GABA)-mediated modulation in neurons. Here we present cryo-electron microscopy (cryo-EM) structures of human potassium-chloride cotransporter KCC1 in potassium chloride or sodium chloride at 2.9- to 3.5-angstrom resolution. KCC1 exists as a dimer, with both extracellular and transmembrane domains involved in dimerization. The structural and functional analyses, along with computational studies, reveal one potassium site and two chloride sites in KCC1, which are all required for the ion transport activity. KCC1 adopts an inward-facing conformation, with the extracellular gate occluded. The KCC1 structures allow us to model a potential ion transport mechanism in KCCs and provide a blueprint for drug design.


  • Organizational Affiliation
    • Department of Biophysics, Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China.

Macromolecule Content 

  • Total Structure Weight: 248.28 kDa 
  • Atom Count: 8,412 
  • Modeled Residue Count: 1,074 
  • Deposited Residue Count: 2,190 
  • Unique protein chains: 1

Macromolecules

Find similar proteins by:|  3D Structure
Entity ID: 1
MoleculeChains  Sequence LengthOrganismDetailsImage
Solute carrier family 12 member 4
A, B
1,095Homo sapiensMutation(s): 0 
Gene Names: SLC12A4KCC1
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for Q9UP95 (Homo sapiens)
Explore Q9UP95 
Go to UniProtKB:  Q9UP95
PHAROS:  Q9UP95
GTEx:  ENSG00000124067 
Entity Groups
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9UP95
Glycosylation
Glycosylation Sites: 2Go to GlyGen: Q9UP95-1
Sequence Annotations
Expand
Reference Sequence

Oligosaccharides

Help  
Entity ID: 2
MoleculeChains Length2D Diagram GlycosylationD Interactions
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose
C, D, G, H
2N-Glycosylation
Glycosylation Resources
GlyTouCan: G42666HT
GlyCosmos: G42666HT
GlyGen: G42666HT
Entity ID: 3
MoleculeChains Length2D Diagram GlycosylationD Interactions
alpha-D-glucopyranose-(1-4)-beta-D-glucopyranose
E, F, I, J
2N/A
Glycosylation Resources
GlyTouCan: G66120GK
GlyCosmos: G66120GK

Small Molecules

Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
DU0

Query on DU0



Download:Ideal Coordinates CCD File
L [auth A],
N [auth B]
2-[2-[(1~{S},2~{S},4~{S},5'~{R},6~{R},7~{S},8~{R},9~{S},12~{S},13~{R},16~{S})-5',7,9,13-tetramethylspiro[5-oxapentacyclo[10.8.0.0^{2,9}.0^{4,8}.0^{13,18}]icos-18-ene-6,2'-oxane]-16-yl]oxyethyl]propane-1,3-diol
C32 H52 O5
GFDJQXOBWHMOSQ-LEZUHYJESA-N
CL

Query on CL



Download:Ideal Coordinates CCD File
K [auth A],
M [auth B]
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.50 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
MODEL REFINEMENTPHENIX

Structure Validation

View Full Validation Report



Entry History 

& Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Ministry of Science and Technology (China)2018YFA0508100
Ministry of Science and Technology (China)2016YFA0500404
National Natural Science Foundation of China31870724
National Natural Science Foundation of China31525001
National Natural Science Foundation of China31430019

Revision History  (Full details and data files)

  • Version 1.0: 2019-10-23
    Type: Initial release
  • Version 1.1: 2019-11-13
    Changes: Data collection, Database references
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Structure summary
  • Version 2.1: 2024-11-20
    Changes: Data collection, Database references, Derived calculations, Structure summary
  • Version 2.2: 2025-07-02
    Changes: Data collection