2VMU

Crystal structure of Y60AbsSHMT crystallized in the presence of L- allo-Thr


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.84 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.195 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural and Functional Studies of Bacillus Stearothermophilus Serine Hydroxymethyltransferase: The Role of Asn(341), Tyr(60) and Phe(351) in Tetrahydrofolate Binding.

Pai, V.R.Rajaram, V.Bisht, S.Bhavani, B.S.Appaji Rao, N.Murthy, M.R.N.Savithri, H.S.

(2009) Biochem.J. 418: 635

  • DOI: 10.1042/BJ20081739
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • SHMT (serine hydoxymethyltransferase), a type I pyridoxal 5'-phosphate-dependent enzyme, catalyses the conversion of L-serine and THF (tetrahydrofolate) into glycine and 5,10-methylene THF. SHMT also catalyses several THF-independent side reactions s ...

    SHMT (serine hydoxymethyltransferase), a type I pyridoxal 5'-phosphate-dependent enzyme, catalyses the conversion of L-serine and THF (tetrahydrofolate) into glycine and 5,10-methylene THF. SHMT also catalyses several THF-independent side reactions such as cleavage of beta-hydroxy amino acids, transamination, racemization and decarboxylation. In the present study, the residues Asn(341), Tyr(60) and Phe(351), which are likely to influence THF binding, were mutated to alanine, alanine and glycine respectively, to elucidate the role of these residues in THF-dependent and -independent reactions catalysed by SHMT. The N341A and Y60A bsSHMT (Bacillus stearothermophilus SHMT) mutants were inactive for the THF-dependent activity, while the mutations had no effect on THF-independent activity. However, mutation of Phe(351) to glycine did not have any effect on either of the activities. The crystal structures of the glycine binary complexes of the mutants showed that N341A bsSHMT forms an external aldimine as in bsSHMT, whereas Y60A and F351G bsSHMTs exist as a mixture of internal/external aldimine and gem-diamine forms. Crystal structures of all of the three mutants obtained in the presence of L-allo-threonine were similar to the respective glycine binary complexes. The structure of the ternary complex of F351G bsSHMT with glycine and FTHF (5-formyl THF) showed that the monoglutamate side chain of FTHF is ordered in both the subunits of the asymmetric unit, unlike in the wild-type bsSHMT. The present studies demonstrate that the residues Asn(341) and Tyr(60) are pivotal for the binding of THF/FTHF, whereas Phe(351) is responsible for the asymmetric binding of FTHF in the two subunits of the dimer.


    Organizational Affiliation

    Department of Biochemistry, Indian Institute of Science, Bangalore, India.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SERINE HYDROXYMETHYLTRANSFERASE
A
405Geobacillus stearothermophilusMutation(s): 1 
Gene Names: glyA
EC: 2.1.2.1
Find proteins for Q7SIB6 (Geobacillus stearothermophilus)
Go to UniProtKB:  Q7SIB6
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
GLY
Query on GLY

Download SDF File 
Download CCD File 
A
GLYCINE
C2 H5 N O2
DHMQDGOQFOQNFH-UHFFFAOYSA-N
 Ligand Interaction
MPD
Query on MPD

Download SDF File 
Download CCD File 
A
(4S)-2-METHYL-2,4-PENTANEDIOL
C6 H14 O2
SVTBMSDMJJWYQN-YFKPBYRVSA-N
 Ligand Interaction
PLP
Query on PLP

Download SDF File 
Download CCD File 
A
PYRIDOXAL-5'-PHOSPHATE
VITAMIN B6 Phosphate
C8 H10 N O6 P
NGVDGCNFYWLIFO-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.84 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.195 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 61.281α = 90.00
b = 106.571β = 90.00
c = 57.190γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
SCALEPACKdata scaling
DENZOdata reduction
REFMACphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-12-16
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance