PDBsum entry 1n2a

Transferase

PDB id: 1n2a

Contents

Protein chains

201 a.a. *

187 a.a. *

Ligands

GTS ×2

Waters ×153

* Residue conservation analysis

PDB id:

1n2a

Name:

Transferase

Title:

Crystal structure of a bacterial glutathione transferase from escherichia coli with glutathione sulfonate in the active site

Structure:

Glutathione s-transferase. Chain: a, b. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Gene: gt_1787923. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Biol. unit:

Dimer (from PQS)

Resolution:

1.90Å R-factor: 0.201 R-free: 0.260

Authors:

C.L.Rife,J.F.Parsons,G.Xiao,G.L.Gilliland,R.N.Armstrong

Key ref:

C.L.Rife et al. (2003). Conserved structural elements in glutathione transferase homologues encoded in the genome of Escherichia coli. Proteins, 53, 777-782. PubMed id: 14635120 DOI: 10.1002/prot.10452

Date:

22-Oct-02 Release date: 04-Nov-03

Protein chain

P0A9D2  (GSTA_ECOLI) -  Glutathione S-transferase GstA from Escherichia coli (strain K12)

Seq: 201 a.a.

Struc: 201 a.a.

Protein chain

P0A9D2  (GSTA_ECOLI) -  Glutathione S-transferase GstA from Escherichia coli (strain K12)

Seq: 201 a.a.

Struc: 187 a.a.

Enzyme reactions

• Enzyme class: Chains A, B: E.C.2.5.1.18 - glutathione transferase.
• Reaction: RX + glutathione = an S-substituted glutathione + a halide anion + H⁺

RX (Bound ligand (Het Group name = GTS) matches with 86.96% similarity) + glutathione = S-substituted glutathione + halide anion + H(+)

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

Added reference

DOI no: 10.1002/prot.10452

Proteins 53:777-782 (2003)

PubMed id: 14635120

Conserved structural elements in glutathione transferase homologues encoded in the genome of Escherichia coli.

C.L.Rife, J.F.Parsons, G.Xiao, G.L.Gilliland, R.N.Armstrong.

ABSTRACT

Multiple sequence alignments of the eight glutathione (GSH) transferase homologues encoded in the genome of Escherichia coli were used to define a consensus sequence for the proteins. The consensus sequence was analyzed in the context of the three-dimensional structure of the gst gene product (EGST) obtained from two different crystal forms of the enzyme. The enzyme consists of two domains. The N-terminal region (domain I) has a thioredoxin-like alpha/beta-fold, while the C-terminal domain (domain II) is all alpha-helical. The majority of the consensus residues (12/17) reside in the N-terminal domain. Fifteen of the 17 residues are involved in hydrophobic core interactions, turns, or electrostatic interactions between the two domains. The results suggest that all of the homologues retain a well-defined group of structural elements both in and between the N-terminal alpha/beta domain and the C-terminal domain. The conservation of two key residues for the recognition motif for the gamma-glutamyl-portion of GSH indicates that the homologues may interact with GSH or GSH analogues such as glutathionylspermidine or alpha-amino acids. The genome context of two of the homologues forms the basis for a hypothesis that the b2989 and yibF gene products are involved in glutathionylspermidine and selenium biochemistry, respectively.

Selected figure(s)

Figure 2.
Figure 2. Distribution of consensus residues in the gst gene product from Escherichia coli. Ribbon diagram of monomer A of EGST illustrating the distribution of conserved residues amongst the homologues. Domains I and II are illustrated in orange and light blue, respectively. The side chains of the 17 consensus residues are highlighted in van der Waals representations.

Figure 5.
Figure 5. View of the -glutamyl binding motif at the turn between -strand-4 and helix-2 in the N-terminal domain. The carboxylate of E65 and the main-chain N-H of G66 are within hydrogen bonding distance of the -amino and -carboxyl groups of the glutamyl residues of GSO [LaTeX2gif.pl?%5Cdocumentclass%7Bminimal%7D%5Cbegin%7Bdocument%7D%5C%28%5E%7B-%7D_%7B3%7D%5C%29%5Cend%7Bdocument%7D] .

The above figures are reprinted by permission from John Wiley & Sons, Inc.: Proteins (2003, 53, 777-782) copyright 2003.

Figures were selected by the author.