1ZOF

Crystal structure of alkyl hydroperoxide-reductase (AhpC) from Helicobacter Pylori

Summary for 1ZOF

• Entry DOI: 10.2210/pdb1zof/pdb
• Descriptor: alkyl hydroperoxide-reductase (2 entities in total)
• Functional Keywords: decamer, toroide-shaped complex, oxidoreductase
• Biological source: Helicobacter pylori
• Total number of polymer chains: 10
• Total formula weight: 222766.52

Authors

Papinutto, E.,Windle, H.J.,Cendron, L.,Battistutta, R.,Kelleher, D.,Zanotti, G. (deposition date: 2005-05-13, release date: 2005-11-29, Last modification date: 2024-10-30)

Primary citation

Papinutto, E.,Windle, H.J.,Cendron, L.,Battistutta, R.,Kelleher, D.,Zanotti, G.
Crystal structure of alkyl hydroperoxide-reductase (AhpC) from Helicobacter pylori.
Biochim.Biophys.Acta, 1753:240-246, 2005

PubMed Abstract: The AhpC protein from H. pylori, a thioredoxin (Trx)-dependent alkyl hydroperoxide-reductase, is a member of the ubiquitous 2-Cys peroxiredoxins family (2-Cys Prxs), a group of thiol-specific antioxidant enzymes. Prxs exert the protective antioxidant role in cells through their peroxidase activity, whereby hydrogen peroxide, peroxynitrite and a wide range of organic hydroperoxides (ROOH) are reduced and detoxified (ROOH + 2e(-)-->ROH + H2O). In this study AhpC has been cloned and overexpressed in E. coli. After purification to homogeneity, crystals of the recombinant protein were grown. They diffract to 2.95 A resolution using synchrotron radiation. The crystal structure of AhpC has been determined using the molecular replacement method (R = 23.6%, R(free) = 25.9%). The model, similar in the overall to other members of the 2-Cys Prx family crystallized as toroide-shaped complexes, consists of a pentameric arrangement of homodimers [(alpha2)5 decamer]. The model of AhpC from H. pylori presents significant differences with respect to other members of the family: apart from some loop regions, alpha5-helix and the C-terminus is shifted, preventing the C-terminal tail of the second subunit from extending toward this region of the molecule. Oligomerization properties of AhpC have been also characterized by gel filtration chromatography.

PubMed: 16213196
DOI: 10.1016/j.bbapap.2005.09.001

Experimental method

X-RAY DIFFRACTION (2.95 Å)