1K8X

Crystal Structure Of AlphaT183V Mutant Of Tryptophan Synthase From Salmonella Typhimurium


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.192 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

On the Role of AlphaThr183 in the Allosteric Regulation and Catalytic Mechanism of Tryptophan Synthase

Kulik, V.Weyand, M.Siedel, R.Niks, D.Arac, D.Dunn, M.F.Schlichting, I.

(2002) J Mol Biol 324: 677-690

  • DOI: 10.1016/s0022-2836(02)01109-9
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The catalytic activity and substrate channeling of the pyridoxal 5'-phosphate-dependent tryptophan synthase alpha(2)beta(2) complex is regulated by allosteric interactions that modulate the switching of the enzyme between open, low activity and close ...

    The catalytic activity and substrate channeling of the pyridoxal 5'-phosphate-dependent tryptophan synthase alpha(2)beta(2) complex is regulated by allosteric interactions that modulate the switching of the enzyme between open, low activity and closed, high activity states during the catalytic cycle. The highly conserved alphaThr183 residue is part of loop alphaL6 and is located next to the alpha-active site and forms part of the alpha-beta subunit interface. The role of the interactions of alphaThr183 in alpha-site catalysis and allosteric regulation was investigated by analyzing the kinetics and crystal structures of the isosteric mutant alphaThr183Val. The mutant displays strongly impaired allosteric alpha-beta communication, and the catalytic activity of the alpha-reaction is reduced one hundred fold, whereas the beta-activity is not affected. The structural work establishes that the basis for the missing inter-subunit signaling is the lack of loop alphaL6 closure even in the presence of the alpha-subunit ligands, 3-indolyl-D-glycerol 3'-phosphate, or 3-indolylpropanol 3'-phosphate. The structural basis for the reduced alpha-activity has its origins in the missing hydrogen bond between alphaThr183 and the catalytic residue, alphaAsp60.


    Organizational Affiliation

    Max Planck Institut für Molekulare Physiologie, Abeilung für Biophysikalische Chemie, Otto Hahn Str 11, 44227 Dortmund, Germany.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TRYPTOPHAN SYNTHASE, ALPHA PROTEIN
A
268Salmonella enterica subsp. enterica serovar TyphimuriumMutation(s): 1 
EC: 4.2.1.20
Find proteins for P00929 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Go to UniProtKB:  P00929

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
TRYPTOPHAN SYNTHASE, BETA PROTEIN
B
397Salmonella enterica subsp. enterica serovar Typhimurium str. LT2Mutation(s): 0 
Gene Names: trpBSTM1726
EC: 4.2.1.20
Find proteins for P0A2K1 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Go to UniProtKB:  P0A2K1
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PLP
Query on PLP

Download CCD File 
B
PYRIDOXAL-5'-PHOSPHATE
C8 H10 N O6 P
NGVDGCNFYWLIFO-UHFFFAOYSA-N
 Ligand Interaction
NA
Query on NA

Download CCD File 
B
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.192 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 182.22α = 90
b = 59.99β = 94.68
c = 67.07γ = 90
Software Package:
Software NamePurpose
MARdata collection
XDSdata reduction
CNSrefinement
MARdata reduction
XDSdata scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-12-18
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Source and taxonomy, Version format compliance