1HTO

CRYSTALLOGRAPHIC STRUCTURE OF A RELAXED GLUTAMINE SYNTHETASE FROM MYCOBACTERIUM TUBERCULOSIS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.228 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Multicopy crystallographic refinement of a relaxed glutamine synthetase from Mycobacterium tuberculosis highlights flexible loops in the enzymatic mechanism and its regulation.

Gill, H.S.Pfluegl, G.M.Eisenberg, D.

(2002) Biochemistry 41: 9863-9872

  • DOI: 10.1021/bi020254s
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The crystal structure of glutamine synthetase (GS) from Mycobacterium tuberculosis determined at 2.4 A resolution reveals citrate and AMP bound in the active site. The structure was refined with strict 24-fold noncrystallographic symmetry (NCS) const ...

    The crystal structure of glutamine synthetase (GS) from Mycobacterium tuberculosis determined at 2.4 A resolution reveals citrate and AMP bound in the active site. The structure was refined with strict 24-fold noncrystallographic symmetry (NCS) constraints and has an R-factor of 22.7% and an R-free of 25.5%. Multicopy refinement using 10 atomic models and strict 24-fold NCS constraints further reduced the R-factor to 20.4% and the R-free to 23.2%. The multicopy model demonstrates the range of atomic displacements of catalytic and regulatory loops in glutamine synthesis, simulating loop motions. A comparison with loop positions in substrate complexes of GS from Salmonella typhimurium shows that the Asp50 and Glu327 loops close over the active site during catalysis. These loop closures are preceded by a conformational change of the Glu209 beta-strand upon metal ion or ATP binding that converts the enzyme from a relaxed to a taut state. We propose a model of the GS regulatory mechanism based on the loop motions in which adenylylation of the Tyr397 loop reverses the effect of metal ion binding, and regulates intermediate formation by preventing closure of the Glu327 loop.


    Organizational Affiliation

    Howard Hughes Medical Institute, UCLA-Department of Energy Laboratory of Structural Biology and Molecular Medicine, Department of Chemistry and Biochemistry, Box 951570, University of California, Los Angeles, CA 90095-1570, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GLUTAMINE SYNTHETASEA, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X477Mycobacterium tuberculosisMutation(s): 0 
EC: 6.3.1.2
Find proteins for P9WN39 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WN39 
Go to UniProtKB:  P9WN39
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
AMP
Query on AMP

Download CCD File 
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X
ADENOSINE MONOPHOSPHATE
C10 H14 N5 O7 P
UDMBCSSLTHHNCD-KQYNXXCUSA-N
 Ligand Interaction
CIT
Query on CIT

Download CCD File 
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X
CITRIC ACID
C6 H8 O7
KRKNYBCHXYNGOX-UHFFFAOYSA-N
 Ligand Interaction
MN
Query on MN

Download CCD File 
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.228 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 207.72α = 90
b = 257.69β = 90
c = 274.5γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORrefinement
MOSFLMdata reduction
CCP4data scaling
ROTAVATAdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-07-24
    Type: Initial release
  • Version 1.1: 2008-04-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-04
    Changes: Refinement description