PDBsum entry 2a2s

Transferase

PDB id: 2a2s

Contents

Protein chain

210 a.a. *

Ligands

MES ×2

GSN ×2

CO3

Metals

_CA

Waters ×527

* Residue conservation analysis

PDB id:

2a2s

Name:

Transferase

Title:

Crystal structure of human glutathione transferase in complex with s- nitrosoglutathione in the absence of reducing agent

Structure:

Glutathione s-transferase p. Chain: a, b. Synonym: glutathione transferase pi, gst class-pi, gstp1-1. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: gstp1. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PQS)

Resolution:

1.70Å R-factor: 0.178 R-free: 0.208

Authors:

L.J.Parker,C.J.Morton,J.J.Adams,M.W.Parker

Key ref:

R.Téllez-Sanz et al. (2006). Calorimetric and structural studies of the nitric oxide carrier S-nitrosoglutathione bound to human glutathione transferase P1-1. Protein Sci, 15, 1093-1105. PubMed id: 16597834 DOI: 10.1110/ps.052055206

Date:

23-Jun-05 Release date: 06-Jun-06

Protein chains

P09211  (GSTP1_HUMAN) -  Glutathione S-transferase P from Homo sapiens

Seq: 210 a.a.

Struc: 210 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 = GSN) matches with 90.91% similarity) + glutathione = S-substituted glutathione + halide anion + H(+)

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

Added reference

DOI no: 10.1110/ps.052055206

Protein Sci 15:1093-1105 (2006)

PubMed id: 16597834

Calorimetric and structural studies of the nitric oxide carrier S-nitrosoglutathione bound to human glutathione transferase P1-1.

R.Téllez-Sanz, E.Cesareo, M.Nuccetelli, A.M.Aguilera, C.Barón, L.J.Parker, J.J.Adams, C.J.Morton, M.Lo Bello, M.W.Parker, L.García-Fuentes.

ABSTRACT

The nitric oxide molecule (NO) is involved in many important physiological processes and seems to be stabilized by reduced thiol species, such as S-nitrosoglutathione (GSNO). GSNO binds strongly to glutathione transferases, a major superfamily of detoxifying enzymes. We have determined the crystal structure of GSNO bound to dimeric human glutathione transferase P1-1 (hGSTP1-1) at 1.4 A resolution. The GSNO ligand binds in the active site with the nitrosyl moiety involved in multiple interactions with the protein. Isothermal titration calorimetry and differential scanning calorimetry (DSC) have been used to characterize the interaction of GSNO with the enzyme. The binding of GSNO to wild-type hGSTP1-1 induces a negative cooperativity with a kinetic process concomitant to the binding process occurring at more physiological temperatures. GSNO inhibits wild-type enzyme competitively at lower temperatures but covalently at higher temperatures, presumably by S-nitrosylation of a sulfhydryl group. The C47S mutation removes the covalent modification potential of the enzyme by GSNO. These results are consistent with a model in which the flexible helix alpha2 of hGST P1-1 must move sufficiently to allow chemical modification of Cys47. In contrast to wild-type enzyme, the C47S mutation induces a positive cooperativity toward GSNO binding. The DSC results show that the thermal stability of the mutant is slightly higher than wild type, consistent with helix alpha2 forming new interactions with the other subunit. All these results suggest that Cys47 plays a key role in intersubunit cooperativity and that under certain pathological conditions S-nitrosylation of Cys47 by GSNO is a likely physiological scenario.

Selected figure(s)

Figure 1.
Stereo diagram of the 2F[o] -- F[c] electron density map of the hGSTP1-1 --GSNO complex at 1.4 A resolution (contoured at the 1[sigma] level). Only one conformer of the nitroso moiety is shown for clarity.

Figure 3.
ITC data for the binding of GSNO to wt-hGSTP1-1 at 35.1[deg]C. Titrations were performed in 20 mM sodium phosphate (pH 7.0), 5 mM NaCl, and 0.1 mM EDTA buffer. Raw data for the titration of enzyme (39.46 [mu]M) with 29 8-[mu]L injections of GSNO (13.95 mM). A preinjection of 1 [mu]L was performed at the beginning. (a) GSNO dilution experiment.

The above figures are reprinted from an Open Access publication published by the Protein Society: Protein Sci (2006, 15, 1093-1105) copyright 2006.

Figures were selected by the author.