Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Biological Assembly 2  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors and generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 74.49 kDa 
• Atom Count: 5515 
• Residue Count: 692 
• Unique protein chains: 1

1USI

L-leucine-binding protein with phenylalanine bound

• DOI: 10.2210/pdb1USI/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Escherichia coli
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2003-11-24 Released: 2003-12-18 
• Deposition Author(s): Magnusson, U., Salopek-Sondi, B., Luck, L.A., Mowbray, S.L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.222 
• R-Value Work: 0.189 
• R-Value Observed: 0.191 

Literature

X-Ray Structures of the Leucine-Binding Protein Illustrate Conformational Changes and the Basis of Ligand Specificity

Magnusson, U., Salopek-Sondi, B., Luck, L.A., Mowbray, S.L.

(2004) J Biol Chem 279: 8747

• PubMed: 14672931 
• DOI: 10.1074/jbc.M311890200
• Primary Citation of Related Structures:  
  1USK, 1USI, 1USG


• PubMed Abstract: 
  

The periplasmic leucine-binding protein is the primary receptor for the leucine transport system in Escherichia coli. We report here the structure of an open ligand-free form solved by molecular replacement and refined at 1.5-A resolution. In addition, two closed ligand-bound structures of the same protein are presented, a phenylalanine-bound form at 1.8 A and a leucine-bound structure at a nominal resolution of 2.4 A. These structures show the basis of this protein's ligand specificity, as well as illustrating the conformational changes that are associated with ligand binding. Comparison with earlier structures provides further information about solution conformations, as well as the different specificity of the closely related leucine/isoleucine/valine-binding protein.

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Organizational Affiliation: 

Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, S-751 24 Uppsala, Sweden.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
LEUCINE-SPECIFIC BINDING PROTEIN	A, C	346	Escherichia coli	Mutation(s): 0
Find proteins for P04816 (Escherichia coli (strain K12)) Explore P04816  Go to UniProtKB:  P04816

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PHE	A, C	PHENYLALANINE C9 H11 N O2 COLNVLDHVKWLRT-QMMMGPOBSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
PHE	Kd :  180   nM  PDBBind
PHE	Kd:  180   nM  Binding MOAD

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.222 
• R-Value Work: 0.189 
• R-Value Observed: 0.191 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 68.236	α = 90
b = 78.143	β = 102.82
c = 70.183	γ = 90

Software Package:

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

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-11-24 
• Released Date: 2003-12-18 
Deposition Author(s): Magnusson, U., Salopek-Sondi, B., Luck, L.A., Mowbray, S.L.

Revision History 

• Version 1.0: 2003-12-18
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-01-17
  Changes: Data collection