1KKB

Complex of Escherichia coli Adenylosuccinate Synthetase with IMP and Hadacidin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.290 
  • R-Value Work: 0.180 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

IMP Alone Organizes the Active Site of Adenylosuccinate Synthetase from Escherichia coli.

Hou, Z.Wang, W.Fromm, H.J.Honzatko, R.B.

(2002) J.Biol.Chem. 277: 5970-5976

  • DOI: 10.1074/jbc.M109561200
  • Primary Citation of Related Structures:  1KJX, 1KKF

  • PubMed Abstract: 
  • A complete set of substrate/substrate analogs of adenylosuccinate synthetase from Escherichia coli induces dimer formation and a transition from a disordered to an ordered active site. The most striking of the ligand-induced effects is the movement o ...

    A complete set of substrate/substrate analogs of adenylosuccinate synthetase from Escherichia coli induces dimer formation and a transition from a disordered to an ordered active site. The most striking of the ligand-induced effects is the movement of loop 40-53 by up to 9 A. Crystal structures of the partially ligated synthetase, which either combine IMP and hadacidin or IMP, hadacidin, and Mg(2+)-pyrophosphate, have ordered active sites, comparable with the fully ligated enzyme. More significantly, a crystal structure of the synthetase with IMP alone exhibits a largely ordered active site, which includes the 9 A movement of loop 40-53 but does not include conformational adjustments to backbone carbonyl 40 (Mg(2+) interaction element) and loop 298-304 (L-aspartate binding element). Interactions involving the 5'-phosphoryl group of IMP evidently trigger the formation of salt links some 30 A away. The above provides a structural basis for ligand binding synergism, effects on k(cat) due to mutations far from the site of catalysis, and the complete loss of substrate efficacy due to minor alterations of the 5'-phosphoryl group of IMP.


    Organizational Affiliation

    Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Adenylosuccinate Synthetase
A
432Escherichia coli (strain K12)Gene Names: purA (adeK)
EC: 6.3.4.4
Find proteins for P0A7D4 (Escherichia coli (strain K12))
Go to UniProtKB:  P0A7D4
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
IMP
Query on IMP

Download SDF File 
Download CCD File 
A
INOSINIC ACID
C10 H13 N4 O8 P
GRSZFWQUAKGDAV-KQYNXXCUSA-N
 Ligand Interaction
HDA
Query on HDA

Download SDF File 
Download CCD File 
A
HADACIDIN
C3 H5 N O4
URJHVPKUWOUENU-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.290 
  • R-Value Work: 0.180 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 80.120α = 90.00
b = 80.120β = 90.00
c = 158.670γ = 120.00
Software Package:
Software NamePurpose
X-GENdata scaling
X-PLORmodel building
X-PLORrefinement
X-GENdata reduction
X-PLORphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-03-20
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description