1EXB | pdb_00001exb

STRUCTURE OF THE CYTOPLASMIC BETA SUBUNIT-T1 ASSEMBLY OF VOLTAGE-DEPENDENT K CHANNELS

• PDB DOI: https://doi.org/10.2210/pdb1EXB/pdb

• Classification: METAL TRANSPORT
• Organism(s): Rattus norvegicus
• Expression System: unidentified baculovirus
• Mutation(s): No 


• Deposited: 2000-05-02 Released: 2000-07-19 
• Deposition Author(s): Gulbis, J.M., Zhou, M., Mann, S., MacKinnon, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 
  0.227 (Depositor), 0.227 (DCC) 
• R-Value Work: 
  0.215 (Depositor), 0.215 (DCC) 
• R-Value Observed: 
  0.216 (Depositor) 

Literature

Structure of the cytoplasmic beta subunit-T1 assembly of voltage-dependent K+ channels.

Gulbis, J.M., Zhou, M., Mann, S., MacKinnon, R.

(2000) Science 289: 123-127

• PubMed: 10884227 
• DOI: https://doi.org/10.1126/science.289.5476.123
• Primary Citation Related Structures: 
  1EXB


• PubMed Abstract: 
  

  The structure of the cytoplasmic assembly of voltage-dependent K+ channels was solved by x-ray crystallography at 2.1 angstrom resolution. The assembly includes the cytoplasmic (T1) domain of the integral membrane alpha subunit together with the oxidoreductase beta subunit in a fourfold symmetric T1(4)beta4 complex. An electrophysiological assay showed that this complex is oriented with four T1 domains facing the transmembrane pore and four beta subunits facing the cytoplasm. The transmembrane pore communicates with the cytoplasm through lateral, negatively charged openings above the T1(4)beta4 complex. The inactivation peptides of voltage-dependent K(+) channels reach their site of action by entering these openings.

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Organizational Affiliation: 
• Howard Hughes Medical Institute and Laboratory of Molecular Neurobiology and Biophysics, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.

Biological Assembly 1  

Global Symmetry: Cyclic - C4  (Explore in 3D)
Global Stoichiometry: Hetero 8-mer - A4B4 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 50.31 kDa 
• Atom Count: 3,628 
• Modeled Residue Count: 417 
• Deposited Residue Count: 435 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
KV BETA2 PROTEIN	A	332	Rattus norvegicus	Mutation(s): 0  EC: 1.1.1
UniProt
Find proteins for P62483 (Rattus norvegicus) Explore P62483  Go to UniProtKB:  P62483

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
POTASSIUM CHANNEL KV1.1	B [auth E]	103	Rattus norvegicus	Mutation(s): 0
UniProt
Find proteins for P10499 (Rattus norvegicus) Explore P10499  Go to UniProtKB:  P10499

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NDP	C [auth A]	NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE C21 H30 N7 O17 P3 ACFIXJIJDZMPPO-NNYOXOHSSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free:  0.227 (Depositor), 0.227 (DCC) 
• R-Value Work:  0.215 (Depositor), 0.215 (DCC) 
• R-Value Observed: 0.216 (Depositor) 

Space Group: P 4 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 100.725	α = 90
b = 100.725	β = 90
c = 110.901	γ = 90

Software Package:

Software Name	Purpose
AMoRE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-07-19 
Deposition Author(s): Gulbis, J.M., Zhou, M., Mann, S., MacKinnon, R.

Revision History  

• Version 1.0: 2000-07-19
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2021-07-21
  Changes: Derived calculations, Refinement description
• Version 1.4: 2024-02-07
  Changes: Data collection, Database references