PDBsum entry 2pvq

Transferase

PDB id: 2pvq

Contents

Protein chain

201 a.a. *

Ligands

SO4 ×2

GSH

Waters ×215

* Residue conservation analysis

PDB id:

2pvq

Name:

Transferase

Title:

Crystal structure of ochrobactrum anthropi glutathione transferase cys10ala mutant with glutathione bound at the h-site

Structure:

Glutathione s-transferase. Chain: a. Engineered: yes. Mutation: yes

Source:

Ochrobactrum anthropi. Organism_taxid: 529. Gene: gst. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.80Å R-factor: 0.200 R-free: 0.248

Authors:

N.Allocati,L.Federici,M.Masulli,B.Favaloro,C.Di Ilio

Key ref:

N.Allocati et al. (2008). Cysteine 10 is critical for the activity of Ochrobactrum anthropi glutathione transferase and its mutation to alanine causes the preferential binding of glutathione to the H-site. Proteins, 71, 16-23. PubMed id: 18076047 DOI: 10.1002/prot.21835

Date:

10-May-07 Release date: 15-Jan-08

Protein chain

P81065  (GST_BRUAN) -  Glutathione S-transferase from Brucella anthropi

Seq: 201 a.a.

Struc: 201 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

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

DOI no: 10.1002/prot.21835

Proteins 71:16-23 (2008)

PubMed id: 18076047

Cysteine 10 is critical for the activity of Ochrobactrum anthropi glutathione transferase and its mutation to alanine causes the preferential binding of glutathione to the H-site.

N.Allocati, L.Federici, M.Masulli, B.Favaloro, C.Di Ilio.

ABSTRACT

The role of the evolutionarily conserved residue Cys10 in Ochrobactrum anthropi glutathione transferase (OaGST) has been examined by replacing it with an alanine. A double mutant C10A/S11A was also prepared. The effect of the replacements on the coniugating and thiotransferase activities, and on the thermal and chemical stability of the enzyme was analyzed. Our data support the view that in OaGST, in contrast with other beta class GSTs that display significant differences in the glutathione-binding site, Cys10 is a key residue for glutathione coniugating activity. Furthermore, analysis of the OaGST-Cys10Ala structure, crystallized in the presence of glutathione, reveals that this mutation causes a switch between the high-affinity G-site and a low-affinity H-site where hydrophobic cosubstrates bind and where we observe the presence of an unexpected glutathione.

Selected figure(s)

Figure 2.
Figure 2. Effect of temperature on the stability of wild-type and mutant OaGST enzymes. The enzyme activity at 25°C was taken as 100%. Wild-type ( ), C10A ( ), C10A/S11A ( ).

Figure 4.
Figure 4. Crystal structure of OaGST-Cys10Ala. A: Close-up view of the H-site with relevant residues and GSH (green carbons) shown in sticks. The 2Fo-Fc map, contoured at 0.9 , is shown in cyan. The GSH-omit Fo-Fc map is shown in orange (contoured at 2.5 ) and magenta (contoured at 2.0 ). B: Superposition of OaGST and BxGST. The surface of OaGST-Cys10Ala is shown in grey. In BxGST both the G-site and the H-site are occupied by GSH molecules (shown in blue). The H-site GSH of OaGST-Cys10Ala is shown in red and it is slightly shifted toward the G-site with respect to the BxGST corresponding one.

The above figures are reprinted by permission from John Wiley & Sons, Inc.: Proteins (2008, 71, 16-23) copyright 2008.

Figures were selected by the author.