Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Pseudo Symmetry: Cyclic - C2  (3D View)
Pseudo Stoichiometry: Homo 2-mer - A2 Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 44.99 kDa 
• Atom Count: 2561 
• Residue Count: 308 
• Unique protein chains: 1

1JHF

LEXA G85D MUTANT

• DOI: 10.2210/pdb1JHF/pdb

• Classification: HYDROLASE
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2001-06-27 Released: 2001-09-19 
• Deposition Author(s): Luo, Y., Pfuetzner, R.A., Mosimann, S., Little, J.W., Strynadka, N.C.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.263 
• R-Value Work: 0.240 

Literature

Crystal structure of LexA: a conformational switch for regulation of self-cleavage.

Luo, Y., Pfuetzner, R.A., Mosimann, S., Paetzel, M., Frey, E.A., Cherney, M., Kim, B., Little, J.W., Strynadka, N.C.

(2001) Cell 106: 585-594

• PubMed: 11551506 
• DOI: 10.1016/s0092-8674(01)00479-2
• Primary Citation of Related Structures:  
  1JHF, 1JHE, 1JHC, 1JHH


• PubMed Abstract: 
  

LexA repressor undergoes a self-cleavage reaction. In vivo, this reaction requires an activated form of RecA, but it occurs spontaneously in vitro at high pH. Accordingly, LexA must both allow self-cleavage and yet prevent this reaction in the absence of a stimulus. We have solved the crystal structures of several mutant forms of LexA. Strikingly, two distinct conformations are observed, one compatible with cleavage, and the other in which the cleavage site is approximately 20 A from the catalytic center. Our analysis provides insight into the structural and energetic features that modulate the interconversion between these two forms and hence the rate of the self-cleavage reaction. We suggest RecA activates the self-cleavage of LexA and related proteins through selective stabilization of the cleavable conformation.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, University of British Columbia, 2146 Health Sciences Mall, Vancouver, British Columbia, V6T 1Z3, Canada.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
LEXA REPRESSOR	A, B	202	Escherichia coli	Mutation(s): 1  Gene Names: lexA EC: 3.4.21.88
Find proteins for P0A7C2 (Escherichia coli (strain K12)) Explore P0A7C2  Go to UniProtKB:  P0A7C2

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	A	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.263 
• R-Value Work: 0.240 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 90.02	α = 90
b = 90.02	β = 90
c = 102.82	γ = 90

Software Package:

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

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-06-27 
• Released Date: 2001-09-19 
Deposition Author(s): Luo, Y., Pfuetzner, R.A., Mosimann, S., Little, J.W., Strynadka, N.C.J.

Revision History 

• Version 1.0: 2001-09-19
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance