1JH9

PURINE REPRESSOR MUTANT-HYPOXANTHINE-PURF OPERATOR COMPLEX


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.55 Å
  • R-Value Observed: 0.219 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Role of residue 147 in the gene regulatory function of the Escherichia coli purine repressor.

Huffman, J.L.Lu, F.Zalkin, H.Brennan, R.G.

(2002) Biochemistry 41: 511-520

  • DOI: 10.1021/bi0156660
  • Primary Citation of Related Structures:  
    1JFT, 1JFS, 1JH9, 1JHZ

  • PubMed Abstract: 
  • The crystal structures of corepressor-bound and free Escherichia coli purine repressor (PurR) have delineated the roles of several residues in corepressor binding and specificity and the intramolecular signal transduction (allosterism) of this LacI/GalR family member ...

    The crystal structures of corepressor-bound and free Escherichia coli purine repressor (PurR) have delineated the roles of several residues in corepressor binding and specificity and the intramolecular signal transduction (allosterism) of this LacI/GalR family member. From these structures, residue W147 was implicated as a key component of the allosteric response, but in many members of the LacI/GalR family, position 147 is occupied by an arginine. To understand the role of this tryptophan at position 147, three proteins, substituted by phenylalanine (W147F), alanine (W147A), or arginine (W147R), were constructed and characterized in vivo and in vitro, and their structures were determined. W147F displays a decreased affinity for corepressor and is a poor repressor in vivo. W147A and W147R, on the other hand, are super repressors and bind corepressor 13.6 and 7.9 times more tightly, respectively, than wild-type. Each mutant PurR-hypoxanthine-purF operator holo complex crystallizes isomorphously to wild-type. Whereas the apo corepressor binding domain (CBD) of W147F crystallizes under those conditions used for the wild-type protein, neither the apo CBD of W147R nor W147A crystallizes, although screened extensively for new crystal forms. Structures of the holo repressor mutants have been solved to resolutions between 2.5 and 2.9 A, and the structure of the apo CBD of W147F has been solved to 2.4 A resolution. These structures provide insight into the altered biochemical properties and physiological functions of these mutants, which appear to depend on the sometimes subtle preference for one conformation (apo vs holo) over the other.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon, USA.



Macromolecules

Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
PURINE NUCLEOTIDE SYNTHESIS REPRESSORB [auth A]340Escherichia coliMutation(s): 1 
Gene Names: purR
UniProt
Find proteins for P0ACP7 (Escherichia coli (strain K12))
Explore P0ACP7 
Go to UniProtKB:  P0ACP7
Protein Feature View
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  • Reference Sequence
  • Find similar nucleic acids by:  Sequence   |   Structure
  • Entity ID: 1
    MoleculeChainsLengthOrganismImage
    5'-D(*AP*AP*CP*GP*AP*AP*AP*AP*CP*GP*TP*TP*TP*TP*CP*GP*T)-3'A [auth B]17N/A
    Protein Feature View
    Expand
    • Reference Sequence
    Small Molecules
    Ligands 2 Unique
    IDChainsName / Formula / InChI Key2D Diagram3D Interactions
    HPA
    Query on HPA

    Download Ideal Coordinates CCD File 
    E [auth A]HYPOXANTHINE
    C5 H4 N4 O
    FDGQSTZJBFJUBT-UHFFFAOYSA-N
     Ligand Interaction
    PO4
    Query on PO4

    Download Ideal Coordinates CCD File 
    C [auth A], D [auth A]PHOSPHATE ION
    O4 P
    NBIIXXVUZAFLBC-UHFFFAOYSA-K
     Ligand Interaction
    External Ligand Annotations 
    IDBinding Affinity (Sequence Identity %)
    DNAKd :  2   nM  PDBBind
    Experimental Data & Validation

    Experimental Data

    • Method: X-RAY DIFFRACTION
    • Resolution: 2.55 Å
    • R-Value Observed: 0.219 
    • Space Group: C 2 2 21
    Unit Cell:
    Length ( Å )Angle ( ˚ )
    a = 175.38α = 90
    b = 92.61β = 90
    c = 80.64γ = 90
    Software Package:
    Software NamePurpose
    TNTrefinement
    MOSFLMdata reduction
    CCP4data scaling
    TNTphasing

    Structure Validation

    View Full Validation Report



    Entry History 

    Deposition Data

    Revision History  (Full details and data files)

    • Version 1.0: 2002-02-08
      Type: Initial release
    • Version 1.1: 2008-04-27
      Changes: Version format compliance
    • Version 1.2: 2011-07-13
      Changes: Version format compliance