PDBsum entry 3ibh

Transferase

PDB id: 3ibh

Contents

Protein chain

208 a.a. *

Ligands

GSH

Waters ×116

* Residue conservation analysis

PDB id:

3ibh

Name:

Transferase

Title:

Crystal structure of saccharomyces cerevisiae gtt2 in complex with glutathione

Structure:

Saccharomyces cerevisiae gtt2. Chain: a. Synonym: gst-ii. Engineered: yes

Source:

Saccharomyces cerevisiae. Organism_taxid: 4932. Strain: s288c. Gene: gtt2, l0560, yll060c. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.10Å R-factor: 0.210 R-free: 0.247

Authors:

X.X.Ma,Y.L.Jiang,Y.X.He,R.Bao,Y.X.Chen,C.Z.Zhou

Key ref:

X.X.Ma et al. (2009). Structures of yeast glutathione-S-transferase Gtt2 reveal a new catalytic type of GST family. Embo Rep, 10, 1320-1326. PubMed id: 19851333

Date:

15-Jul-09 Release date: 13-Oct-09

Protein chain

Q12390  (GST2_YEAST) -  Glutathione S-transferase 2 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 233 a.a.

Struc: 208 a.a.

Enzyme reactions

• Enzyme class: 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 = GSH) corresponds exactly) + glutathione = S-substituted glutathione + halide anion + H(+)

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

Added reference

Embo Rep 10:1320-1326 (2009)

PubMed id: 19851333

Structures of yeast glutathione-S-transferase Gtt2 reveal a new catalytic type of GST family.

X.X.Ma, Y.L.Jiang, Y.X.He, R.Bao, Y.Chen, C.Z.Zhou.

ABSTRACT

Glutathione-S-transferases (GSTs) are ubiquitous detoxification enzymes that catalyse the conjugation of electrophilic substrates to glutathione. Here, we present the crystal structures of Gtt2, a GST of Saccharomyces cerevisiae, in apo and two ligand-bound forms, at 2.23 A, 2.20 A and 2.10 A, respectively. Although Gtt2 has the overall structure of a GST, the absence of the classic catalytic essential residues--tyrosine, serine and cysteine--distinguishes it from all other cytosolic GSTs of known structure. Site-directed mutagenesis in combination with activity assays showed that instead of the classic catalytic residues, a water molecule stabilized by Ser129 and His123 acts as the deprotonator of the glutathione sulphur atom. Furthermore, only glycine and alanine are allowed at the amino-terminus of helix-alpha1 because of stereo-hindrance. Taken together, these results show that yeast Gtt2 is a novel atypical type of cytosolic GST.