2VF4

E. coli glucosamine-6-P synthase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.95 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.219 
  • R-Value Observed: 0.220 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Ordering of C-Terminal Loop and Glutaminase Domains of Glucosamine-6-Phosphate Synthase Promotes Sugar Ring Opening and Formation of the Ammonia Channel.

Mouilleron, S.Badet-Denisot, M.-A.Golinelli-Pimpaneau, B.

(2008) J Mol Biol 377: 1174

  • DOI: 10.1016/j.jmb.2008.01.077
  • Primary Citation of Related Structures:  
    2VF5, 2VF4

  • PubMed Abstract: 
  • Glucosamine-6-phosphate synthase (GlmS) channels ammonia from glutamine at the glutaminase site to fructose 6-phosphate (Fru6P) at the synthase site. Escherichia coli GlmS is composed of two C-terminal synthase domains that form the dimer interface and two N-terminal glutaminase domains at its periphery ...

    Glucosamine-6-phosphate synthase (GlmS) channels ammonia from glutamine at the glutaminase site to fructose 6-phosphate (Fru6P) at the synthase site. Escherichia coli GlmS is composed of two C-terminal synthase domains that form the dimer interface and two N-terminal glutaminase domains at its periphery. We report the crystal structures of GlmS alone and in complex with the glucosamine-6-phosphate product at 2.95 A and 2.9 A resolution, respectively. Surprisingly, although the whole protein is present in this crystal form, no electron density for the glutaminase domain was observed, indicating its mobility. Comparison of the two structures with that of the previously reported GlmS-Fru6P complex shows that, upon sugar binding, the C-terminal loop, which forms the major part of the channel walls, becomes ordered and covers the synthase site. The ordering of the glutaminase domains likely follows Fru6P binding by the anchoring of Trp74, which acts as the gate of the channel, on the closed C-terminal loop. This is accompanied by a major conformational change of the side chain of Lys503# of the neighboring synthase domain that strengthens the interactions of the synthase domain with the C-terminal loop and completely shields the synthase site. The concomitant conformational change of the Lys503#-Gly505# tripeptide places catalytic His504# in the proper position to open the sugar and buries the linear sugar, which is now in the vicinity of the catalytic groups involved in the sugar isomerization reaction. Together with the previously reported structures of GlmS in complex with Fru6P or glucose 6-phosphate and a glutamine analogue, the new structures reveal the structural changes occurring during the whole catalytic cycle.


    Organizational Affiliation

    Laboratoire d'Enzymologie et Biochimie Structurales, Bâtiment 34. CNRS, 1 avenue de la Terrasse, 91190 Gif-sur-Yvette, France.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
GLUCOSAMINE--FRUCTOSE-6-PHOSPHATE AMINOTRANSFERASEA [auth X]608Escherichia coliMutation(s): 0 
EC: 2.6.1.16
Find proteins for P17169 (Escherichia coli (strain K12))
Explore P17169 
Go to UniProtKB:  P17169
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.95 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.219 
  • R-Value Observed: 0.220 
  • Space Group: H 3 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 144.704α = 90
b = 144.704β = 90
c = 171.779γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling
REFMACphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-03-04
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance