2R6G

The Crystal Structure of the E. coli Maltose Transporter


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.242 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structure of a catalytic intermediate of the maltose transporter.

Oldham, M.L.Khare, D.Quiocho, F.A.Davidson, A.L.Chen, J.

(2007) Nature 450: 515-521

  • DOI: 10.1038/nature06264

  • PubMed Abstract: 
  • The maltose uptake system of Escherichia coli is a well-characterized member of the ATP-binding cassette transporter superfamily. Here we present the 2.8-A crystal structure of the intact maltose transporter in complex with the maltose-binding protei ...

    The maltose uptake system of Escherichia coli is a well-characterized member of the ATP-binding cassette transporter superfamily. Here we present the 2.8-A crystal structure of the intact maltose transporter in complex with the maltose-binding protein, maltose and ATP. This structure, stabilized by a mutation that prevents ATP hydrolysis, captures the ATP-binding cassette dimer in a closed, ATP-bound conformation. Maltose is occluded within a solvent-filled cavity at the interface of the two transmembrane subunits, about halfway into the lipid bilayer. The binding protein docks onto the entrance of the cavity in an open conformation and serves as a cap to ensure unidirectional translocation of the sugar molecule. These results provide direct evidence for a concerted mechanism of transport in which solute is transferred from the binding protein to the transmembrane subunits when the cassette dimer closes to hydrolyse ATP.


    Organizational Affiliation

    Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Maltose/maltodextrin import ATP-binding protein malK
A, B
381Escherichia coli (strain K12)Mutation(s): 1 
Gene Names: malK
EC: 7.5.2.1
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MalFGK2-MBP Maltose uptake transporter complex
Find proteins for P68187 (Escherichia coli (strain K12))
Go to UniProtKB:  P68187
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Maltose-binding periplasmic protein
E
370Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: malE
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MalFGK2-MBP Maltose uptake transporter complex
Find proteins for P0AEX9 (Escherichia coli (strain K12))
Go to UniProtKB:  P0AEX9
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Maltose transport system permease protein malF
F
514Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: malF
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MalFGK2-MBP Maltose uptake transporter complex
Find proteins for P02916 (Escherichia coli (strain K12))
Go to UniProtKB:  P02916
Entity ID: 4
MoleculeChainsSequence LengthOrganismDetails
Maltose transport system permease protein malG
G
296Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: malG
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MalFGK2-MBP Maltose uptake transporter complex
Find proteins for P68183 (Escherichia coli (strain K12))
Go to UniProtKB:  P68183
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download SDF File 
Download CCD File 
A, B
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
MAL
Query on MAL

Download SDF File 
Download CCD File 
F
MALTOSE
C12 H22 O11
GUBGYTABKSRVRQ-ASMJPISFSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.242 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 73.260α = 87.13
b = 95.860β = 82.43
c = 109.990γ = 75.75
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
HKL-2000data scaling
PHASERphasing
HKL-2000data reduction
PDB_EXTRACTdata extraction
Blu-Icedata collection
DMphasing
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-11-27
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Source and taxonomy, Version format compliance
  • Version 1.2: 2017-10-25
    Type: Refinement description
  • Version 1.3: 2018-01-24
    Type: Structure summary