PDBsum entry: 2bl4

Oxidoreductase

PDB id: 2bl4

Contents

Protein chains

382 a.a. *

Ligands

NAD ×2

Metals

_CL

FE2 ×2

Waters ×47

* Residue conservation analysis

PDB id:

2bl4

Name:

Oxidoreductase

Title:

Lactaldehyde:1,2-propanediol oxidoreductase of escherichia coli

Structure:

Lactaldehyde reductase. Chain: a, b. Synonym: propanediol oxidoreductase, lactaldehyde-1,2 -propanediol oxidoreductase. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Strain: ecl1. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PDB file)

Resolution:

2.85Å R-factor: 0.254 R-free: 0.303

Authors:

C.Montella,L.Bellsolell,R.Perez-Luque,J.Badia,L.Baldoma, M.Coll,J.Aguilar

Key ref:

C.Montella et al. (2005). Crystal structure of an iron-dependent group III dehydrogenase that interconverts L-lactaldehyde and L-1,2-propanediol in Escherichia coli. J Bacteriol, 187, 4957-4966. PubMed id: 15995211 DOI: 10.1128/JB.187.14.4957-4966.2005

Date:

01-Mar-05 Release date: 06-Jul-05

Protein chains

P0A9S1  (FUCO_ECOLI) -  Lactaldehyde reductase

Seq: 382 a.a.

Struc: 382 a.a.

Enzyme reactions

• Enzyme class: E.C.1.1.1.77 - Lactaldehyde reductase.
• Reaction:
  1. (R)-propane-1,2-diol + NAD⁺ = (R)-lactaldehyde + NADH
  2. (S)-propane-1,2-diol + NAD⁺ = (S)-lactaldehyde + NADH

(R)-propane-1,2-diol + NAD(+) (Bound ligand (Het Group name = NAD) corresponds exactly) = (R)-lactaldehyde + NADH

(S)-propane-1,2-diol + NAD(+) (Bound ligand (Het Group name = NAD) corresponds exactly) = (S)-lactaldehyde + NADH

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

 Gene Ontology (GO) functional annotation 

• Biological process: oxidation-reduction process (3 terms)
• Biochemical function: oxidoreductase activity (3 terms)

reference

DOI no: 10.1128/JB.187.14.4957-4966.2005

J Bacteriol 187:4957-4966 (2005)

PubMed id: 15995211

Crystal structure of an iron-dependent group III dehydrogenase that interconverts L-lactaldehyde and L-1,2-propanediol in Escherichia coli.

C.Montella, L.Bellsolell, R.Pérez-Luque, J.Badía, L.Baldoma, M.Coll, J.Aguilar.

ABSTRACT

The FucO protein, a member of the group III "iron-activated" dehydrogenases, catalyzes the interconversion between L-lactaldehyde and L-1,2-propanediol in Escherichia coli. The three-dimensional structure of FucO in a complex with NAD(+) was solved, and the presence of iron in the crystals was confirmed by X-ray fluorescence. The FucO structure presented here is the first structure for a member of the group III bacterial dehydrogenases shown experimentally to contain iron. FucO forms a dimer, in which each monomer folds into an alpha/beta dinucleotide-binding N-terminal domain and an all-alpha-helix C-terminal domain that are separated by a deep cleft. The dimer is formed by the swapping (between monomers) of the first chain of the beta-sheet. The binding site for Fe(2+) is located at the face of the cleft formed by the C-terminal domain, where the metal ion is tetrahedrally coordinated by three histidine residues (His200, His263, and His277) and an aspartate residue (Asp196). The glycine-rich turn formed by residues 96 to 98 and the following alpha-helix is part of the NAD(+) recognition locus common in dehydrogenases. Site-directed mutagenesis and enzyme kinetic assays were performed to assess the role of different residues in metal, cofactor, and substrate binding. In contrast to previous assumptions, the essential His267 residue does not interact with the metal ion. Asp39 appears to be the key residue for discriminating against NADP(+). Modeling L-1,2-propanediol in the active center resulted in a close approach of the C-1 hydroxyl of the substrate to C-4 of the nicotinamide ring, implying that there is a typical metal-dependent dehydrogenation catalytic mechanism.