1P0E

CRYSTAL STRUCTURE OF ZYMOMONAS MOBILIS tRNA-GUANINE TRANSGLYCOSYLASE (TGT) COCRYSTALLISED WITH PREQ1 AT PH 5.5


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.206 
  • R-Value Observed: 0.206 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.4 of the entry. See complete history


Literature

Flexible adaptations in the structure of the tRNA-modifying enzyme tRNA-guanine transglycosylase and their implications for substrate selectivity, reaction mechanism and structure-based drug design

Brenk, R.Stubbs, M.T.Heine, A.Reuter, K.Klebe, G.

(2003) Chembiochem 4: 1066-1077

  • DOI: https://doi.org/10.1002/cbic.200300644
  • Primary Citation of Related Structures:  
    1OZM, 1OZQ, 1P0B, 1P0D, 1P0E

  • PubMed Abstract: 

    The enzyme tRNA-guanine transglycosylase (TGT, EC 2.4.2.29) catalyses a base-exchange reaction that leads to anticodon modifications of certain tRNAs. The TGT enzymes of the eubacteria Zymomonas mobilis (Z. mobilis TGT) and Escherichia coli (E. coli TGT) show a different behaviour in the presence of competitive inhibitors. The active sites of both enzymes are identical apart from a single conservative amino acid exchange, namely Tyr106 of Z. mobilis TGT is replaced by a Phe in E. coli TGT. Although Tyr106 is, in contrast to Phe106, hydrogen bonded in the ligand-free structure, we can show by a mutational study of TGT(Y106F) that this is not the reason for the different responses upon competition. The TGT enzymes of various species differ in their substrate selectivity. Depending on the applied pH conditions and/or induced by ligand binding, a peptide-bond flip modulates the recognition properties of the substrate binding site, which changes between donor and acceptor functionality. Furthermore interstitial water molecules play an important role in these adaptations of the pocket. The flip of the peptide bond is further stabilised by a glutamate residue that operates as general acid/base. An active-site aspartate residue, presumed to operate as a nucleophile through covalent bonding during the base-exchange reaction, shows different conformations depending on the nature of the bound ligand. The induced-fit adaptations observed in the various TGT complex structures by multiple crystal-structure analyses are in agreement with the functional properties of the enzyme. In consequence, full understanding of this plasticity can be exploited for drug design.


  • Organizational Affiliation

    Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032 Marburg, Germany.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Queuine tRNA-ribosyltransferase386Zymomonas mobilisMutation(s): 0 
Gene Names: TGT
EC: 2.4.2.29
UniProt
Find proteins for P28720 (Zymomonas mobilis subsp. mobilis (strain ATCC 31821 / ZM4 / CP4))
Explore P28720 
Go to UniProtKB:  P28720
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP28720
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.206 
  • R-Value Observed: 0.206 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 64.47α = 90
b = 91.87β = 90
c = 165.83γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
HKL-2000data reduction
AMoREphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2003-09-30
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2020-08-19
    Changes: Advisory, Database references, Derived calculations
  • Version 1.4: 2023-08-16
    Changes: Advisory, Data collection, Database references, Refinement description