Sandbox Reserved 186

spinqualitylabelsall models Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

'

Contents 1 Glutathione Peroxidase 1 2 Overview 3 Secondary Structure and the Thioredoxin Like Fold 4 Relevance 5 Structural highlights 6 References

Glutathione Peroxidase 1

Overview

Glutathione peroxidase 1 (GPx-1) is a tetramer (23 kDa per monomer) with two units composed of dimers. GPx-1 is the most abundant member of the Glutathione peroxidase family. It is found in all cells and is located in the cytosolic and mitochondrial compartments (1). GPx-1 is a crucial anti-oxidant enzyme that catalyzes the conversion of hydrogen peroxide into water (2). Interestingly GPx-1 contains the rare amino acid selenocysteine which acts as the peroxidatic residue (2). The overall reaction that GPx-1 catalyzes is H2O2 + 2Glutathione (GSH) -> 2H20 + GS-SG (Figure 1). In addition to hydrogen peroxide GPx-1 can reduce other soluble hydroperoxides including lipid hydroperoxides (3). Because of its role in regulating the intracellular concentration of reactive oxygen species, GPx-1 has been found to play a role in numerous processes including cell proliferation, apoptosis, and inflammation (1). Furthermore deficiencies in GPx-1 has been linked to the development of cancers, neurodegenerative diseases, and heart disease (4).

Secondary Structure and the Thioredoxin Like Fold

The secondary structure of GPx-1 consists of nine β-strands and nine α-helices with five of the helices being of the 310 form (Figure 2). Interestingly two of the β-strands form a parallel β-sheet (Figure 3). GPx-1 exhibits a thioredoxin like fold. The classic thioredoxin fold consists of a four stranded β-sheet that is surrounded by three α-helices (5). However the thioredoxin fold is commonly subject to the insertion of additional secondary structural elements between the second β-strand and the second α-helices (6). This is seen in GPx-1 as there is an addition of an α-helix and a β-strand between the second β-strand and the second α-helices (6). A similar insertion is found in peroxiredoxins, a different family of proteins which also catalyze the reduction of hydroperoxides(6).

Relevance

Structural highlights

This is a sample scene created with SAT to by Group, and another to make of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes.

</StructureSection>

References