PDBsum entry: 2fmn

Oxidoreductase

PDB id: 2fmn

Contents

Protein chains

288 a.a. *

271 a.a. *

Ligands

FAD ×3

4HF ×3

Waters ×281

* Residue conservation analysis

PDB id:

2fmn

Name:

Oxidoreductase

Title:

Ala177val mutant of e. Coli methylenetetrahydrofolate reductase complex with ly309887

Structure:

5,10-methylenetetrahydrofolate reductase. Chain: a, b, c. Engineered: yes. Mutation: yes

Source:

Escherichia coli. Organism_taxid: 562. Gene: metf. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PDB file)

Resolution:

2.05Å R-factor: 0.217 R-free: 0.250

Authors:

R.Pejchal,E.Campbell,B.D.Guenther,B.W.Lennon,R.G.Matthews, M.L.Ludwig

Key ref:

R.Pejchal et al. (2006). Structural perturbations in the Ala --> Val polymorphism of methylenetetrahydrofolate reductase: how binding of folates may protect against inactivation. Biochemistry, 45, 4808-4818. PubMed id: 16605249 DOI: 10.1021/bi052294c

Date:

09-Jan-06 Release date: 25-Apr-06

Protein chains

P0AEZ1  (METF_ECOLI) -  5,10-methylenetetrahydrofolate reductase

Seq: 296 a.a.

Struc: 288 a.a.*

Protein chain

P0AEZ1  (METF_ECOLI) -  5,10-methylenetetrahydrofolate reductase

Seq: 296 a.a.

Struc: 271 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chains A, B, C: E.C.1.5.1.20 - Methylenetetrahydrofolate reductase (NAD(P)H).
• Pathway: Folate Coenzymes
• Reaction: 5-methyltetrahydrofolate + NAD(P)(+) = 5,10-methylenetetrahydrofolate + NAD(P)H
• Cofactor: FAD

FAD (Bound ligand (Het Group name = FAD) corresponds exactly)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

 Gene Ontology (GO) functional annotation 

• Biological process: oxidation reduction (4 terms)
• Biochemical function: oxidoreductase activity (2 terms)

reference

DOI no: 10.1021/bi052294c

Biochemistry 45:4808-4818 (2006)

PubMed id: 16605249

Structural perturbations in the Ala --> Val polymorphism of methylenetetrahydrofolate reductase: how binding of folates may protect against inactivation.

R.Pejchal, E.Campbell, B.D.Guenther, B.W.Lennon, R.G.Matthews, M.L.Ludwig.

ABSTRACT

In human methylenetetrahydrofolate reductase (MTHFR) the Ala222Val (677C-->T) polymorphism encodes a heat-labile gene product that is associated with elevated levels of homocysteine and possibly with risk for cardiovascular disease. Generation of the equivalent Ala to Val mutation in Escherichia coli MTHFR, which is 30% identical to the catalytic domain of the human enzyme, creates a protein with enhanced thermolability. In both human and E. coli MTHFR, the A --> V mutation increases the rate of dissociation of FAD, and in both enzymes, loss of FAD is linked to changes in quaternary structure [Yamada, K., Chen, Z., Rozen, R., and Matthews, R. G. (2001) Proc. Natl. Acad. Sci. U.S.A. 98, 14853-14858; Guenther, B. D., Sheppard, C. A., Tran, P., Rozen, R., Matthews, R. G., and Ludwig, M. L. (1999) Nat. Struct. Biol. 6, 359-365]. Folates have been shown to protect both human and bacterial enzymes from loss of FAD. Despite its effect on affinity for FAD, the A --> V mutation is located at the bottom of the (betaalpha)(8) barrel of the catalytic domain in a position that does not contact the bound FAD prosthetic group. Here we report the structures of the Ala177Val mutant of E. coli MTHFR and of its complex with the 5,10-dideazafolate analogue, LY309887, and suggest mechanisms by which the mutation may perturb FAD binding. Helix alpha5, which immediately precedes the loop bearing the mutation, carries several residues that interact with FAD, including Asn168, Arg171, and Lys172. In the structures of the mutant enzyme this helix is displaced, perturbing protein-FAD interactions. In the complex with LY309887, the pterin-like ring of the analogue stacks against the si face of the flavin and is secured by hydrogen bonds to residues Gln183 and Asp120 that adjoin this face. The direct interactions of bound folate with the cofactor provide one mechanism for linkage between binding of FAD and folate binding that could account in part for the protective action of folates. Conformation changes induced by folate binding may also suppress dissociation of FAD.