1TRR

TANDEM BINDING IN CRYSTALS OF A TRP REPRESSOR/OPERATOR HALF-SITE COMPLEX

• PDB DOI: https://doi.org/10.2210/pdb1TRR/pdb
• NAKB: 1TRR

• Classification: TRANSCRIPTION/DNA
• Organism(s): Escherichia coli
• Mutation(s): No 


• Deposited: 1993-10-21 Released: 1993-10-21 
• Deposition Author(s): Lawson, C.L., Carey, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Work: 0.241 
• R-Value Observed: 0.241 

Literature

Tandem binding in crystals of a trp repressor/operator half-site complex.

Lawson, C.L., Carey, J.

(1993) Nature 366: 178-182

• PubMed: 8232559 
• DOI: https://doi.org/10.1038/366178a0
• Primary Citation of Related Structures:  
  1TRR


• PubMed Abstract: 
  

  The crystal structure of trp repressor tandemly bound in a 2:1 complex to a 16-base-pair palindromic DNA containing a central trp operator half-site has been determined and refined to 2.4 A resolution. Despite dramatically different DNA sequence contexts and crystallization conditions, the protein/DNA interface is essentially identical to that seen in the original trp repressor/operator complex structure. Water-mediated sequence recognition by trp repressor is likely to be related to the unusual end-on approach of the recognition helix (E), which allows sharing of the major groove by tandem dimers. The tandem complex model accounts for the mutational sensitivity of all trp operator base pairs. The structure also provides the first detailed view of the tandem interaction, revealing a key role for the amino-terminal arms.

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Organizational Affiliation: 

Biology Department, Brookhaven National Laboratory, Upton, New York 11973.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 119.15 kDa 
• Atom Count: 8,300 
• Modelled Residue Count: 904 
• Deposited Residue Count: 920 
• Unique protein chains: 1
• Unique nucleic acid chains: 1

Macromolecules

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (TRP REPRESSOR)	E [auth A], F [auth B], G [auth D], H [auth E], I [auth G], J [auth H], K [auth J], L [auth K]	107	Escherichia coli	Mutation(s): 0
UniProt
Find proteins for P0A881 (Escherichia coli (strain K12)) Explore P0A881  Go to UniProtKB:  P0A881

Entity ID: 1
Molecule	Chains	Length	Organism	Image
DNA (5'-D(*AP*GP*CP*GP*TP*AP*CP*TP*AP*GP*TP*AP*CP*GP*CP*T)-3')	A [auth C], B [auth F], C [auth I], D [auth L]	16	N/A

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
TRP	M [auth A], N [auth A], O [auth D], P [auth E], Q [auth G], R [auth H], S [auth J], T [auth K]	TRYPTOPHAN C11 H12 N2 O2 QIVBCDIJIAJPQS-VIFPVBQESA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Work: 0.241 
• R-Value Observed: 0.241 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 112.34	α = 90
b = 90.16	β = 113.92
c = 58.65	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 1993-10-21 
Deposition Author(s): Lawson, C.L., Carey, J.

Revision History  

• Version 1.0: 1993-10-21
  Type: Initial release
  
• Version 1.1: 2008-05-22
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-04-18
  Changes: Data collection
• Version 1.4: 2024-02-14
  Changes: Data collection, Database references, Derived calculations