3FSU

Crystal Structure of Escherichia coli Methylenetetrahydrofolate Reductase Double Mutant Phe223LeuGlu28Gln complexed with methyltetrahydrofolate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.197 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Functional role for the conformationally mobile phenylalanine 223 in the reaction of methylenetetrahydrofolate reductase from Escherichia coli.

Lee, M.N.Takawira, D.Nikolova, A.P.Ballou, D.P.Furtado, V.C.Phung, N.L.Still, B.R.Thorstad, M.K.Tanner, J.J.Trimmer, E.E.

(2009) Biochemistry 48: 7673-7685

  • DOI: 10.1021/bi9007325
  • Primary Citation of Related Structures:  3FST

  • PubMed Abstract: 
  • The flavoprotein methylenetetrahydrofolate reductase from Escherichia coli catalyzes the reduction of 5,10-methylenetetrahydrofolate (CH(2)-H(4)folate) by NADH via a ping-pong reaction mechanism. Structures of the reduced enzyme in complex with NADH ...

    The flavoprotein methylenetetrahydrofolate reductase from Escherichia coli catalyzes the reduction of 5,10-methylenetetrahydrofolate (CH(2)-H(4)folate) by NADH via a ping-pong reaction mechanism. Structures of the reduced enzyme in complex with NADH and of the oxidized Glu28Gln enzyme in complex with CH(3)-H(4)folate [Pejchal, R., Sargeant, R., and Ludwig, M. L. (2005) Biochemistry 44, 11447-11457] have revealed Phe223 as a conformationally mobile active site residue. In the NADH complex, the NADH adopts an unusual hairpin conformation and is wedged between the isoalloxazine ring of the FAD and the side chain of Phe223. In the folate complex, Phe223 swings out from its position in the NADH complex to stack against the p-aminobenzoate ring of the folate. Although Phe223 contacts each substrate in E. coli MTHFR, this residue is not invariant; for example, a leucine occurs at this site in the human enzyme. To examine the role of Phe223 in substrate binding and catalysis, we have constructed mutants Phe223Ala and Phe223Leu. As predicted, our results indicate that Phe223 participates in the binding of both substrates. The Phe223Ala mutation impairs NADH and CH(2)-H(4)folate binding each 40-fold yet slows catalysis of both half-reactions less than 2-fold. Affinity for CH(2)-H(4)folate is unaffected by the Phe223Leu mutation, and the variant catalyzes the oxidative half-reaction 3-fold faster than the wild-type enzyme. Structures of ligand-free Phe223Leu and Phe223Leu/Glu28Gln MTHFR in complex with CH(3)-H(4)folate have been determined at 1.65 and 1.70 A resolution, respectively. The structures show that the folate is bound in a catalytically competent conformation, and Leu223 undergoes a conformational change similar to that observed for Phe223 in the Glu28Gln-CH(3)-H(4)folate structure. Taken together, our results suggest that Leu may be a suitable replacement for Phe223 in the oxidative half-reaction of E. coli MTHFR.


    Organizational Affiliation

    Department of Chemistry, Grinnell College, Grinnell, Iowa 50112, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
5,10-methylenetetrahydrofolate reductase
A, C, E
304Escherichia coli (strain K12)Gene Names: metF
EC: 1.5.1.20
Find proteins for P0AEZ1 (Escherichia coli (strain K12))
Go to UniProtKB:  P0AEZ1
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
C2F
Query on C2F

Download SDF File 
Download CCD File 
A, E
5-METHYL-5,6,7,8-TETRAHYDROFOLIC ACID
C20 H25 N7 O6
ZNOVTXRBGFNYRX-STQMWFEESA-N
 Ligand Interaction
SO4
Query on SO4

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Download CCD File 
E
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
FAD
Query on FAD

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Download CCD File 
A, C, E
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
 Ligand Interaction
MRY
Query on MRY

Download SDF File 
Download CCD File 
C
MESO-ERYTHRITOL
C4 H10 O4
UNXHWFMMPAWVPI-ZXZARUISSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.197 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 102.913α = 90.00
b = 127.906β = 121.73
c = 97.606γ = 90.00
Software Package:
Software NamePurpose
d*TREKdata scaling
PHENIXrefinement
d*TREKdata reduction
PDB_EXTRACTdata extraction
PHENIXphasing
d*TREKdata processing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2009-01-12 
  • Released Date: 2009-08-25 
  • Deposition Author(s): Tanner, J.J.

Revision History 

  • Version 1.0: 2009-08-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance