1Q1E

The ATPase component of E. coli maltose transporter (MalK) in the nucleotide-free form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.244 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A tweezers-like motion of the ATP-binding cassette dimer in an ABC transport cycle

Chen, J.Lu, G.Lin, J.Davidson, A.L.Quiocho, F.A.

(2003) Mol.Cell 12: 651-661

  • Primary Citation of Related Structures:  1Q12, 1Q1B

  • PubMed Abstract: 
  • The ATPase components of ATP binding cassette (ABC) transporters power the transporters by binding and hydrolyzing ATP. Major conformational changes of an ATPase are revealed by crystal structures of MalK, the ATPase subunit of the maltose transporte ...

    The ATPase components of ATP binding cassette (ABC) transporters power the transporters by binding and hydrolyzing ATP. Major conformational changes of an ATPase are revealed by crystal structures of MalK, the ATPase subunit of the maltose transporter from Escherichia coli, in three different dimeric configurations. While other nucleotide binding domains or subunits display low affinity for each other in the absence of the transmembrane segments, the MalK dimer is stabilized through interactions of the additional C-terminal domains. In the two nucleotide-free structures, the N-terminal nucleotide binding domains are separated to differing degrees, and the dimer is maintained through contacts of the C-terminal regulatory domains. In the ATP-bound form, the nucleotide binding domains make contact and two ATPs lie buried along the dimer interface. The two nucleotide binding domains of the dimer open and close like a pair of tweezers, suggesting a regulatory mechanism for ATPase activity that may be tightly coupled to translocation.


    Organizational Affiliation

    Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA . chenjue@bilbo.bio.purdue.edu




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Maltose/maltodextrin transport ATP-binding protein malK
A, B
381Escherichia coli (strain K12)Gene Names: malK
EC: 3.6.3.19
Find proteins for P68187 (Escherichia coli (strain K12))
Go to UniProtKB:  P68187
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.244 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 64.615α = 90.00
b = 102.041β = 107.10
c = 99.288γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
CNSrefinement
AMoREphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-09-30
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance