CATH Classification
Level | CATH Code | Description |
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3 | Alpha Beta |
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3.30 | 2-Layer Sandwich |
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3.30.1020 | Antioxidant, Horf6; Chain A, domain 2 |
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3.30.1020.10 | Antioxidant, Horf6; Chain A, domain2 |
Domain Context
CATH Clusters
Superfamily | Antioxidant, Horf6; Chain A, domain2 |
Functional Family |
Enzyme Information
1.11.1.15 |
Peroxiredoxin.
based on mapping to UniProt Q9Y9L0
2 R'-SH + ROOH = R'-S-S-R' + H(2)O + ROH.
-!- Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant proteins. -!- They can be divided into three classes: typical 2-Cys, atypical 2-Cys and 1-Cys peroxiredoxins. -!- The peroxidase reaction comprises two steps centered around a redox- active cysteine called the peroxidatic cysteine. -!- All three peroxiredoxin classes have the first step in common, in which the peroxidatic cysteine attacks the peroxide substrate and is oxidized to S-hydroxycysteine (a sulfenic acid). -!- The second step of the peroxidase reaction, the regeneration of cysteine from S-hydroxycysteine, distinguishes the three peroxiredoxin classes. -!- For typical 2-Cys Prxs, in the second step, the peroxidatic S-hydroxycysteine from one subunit is attacked by the 'resolving' cysteine located in the C-terminus of the second subunit, to form an intersubunit disulfide bond, which is then reduced by one of several cell-specific thiol-containing reductants (R'-SH) (e.g. thioredoxin, AhpF, tryparedoxin or AhpD), completing the catalytic cycle. -!- In the atypical 2-Cys Prxs, both the peroxidatic cysteine and its resolving cysteine are in the same polypeptide, so their reaction forms an intrachain disulfide bond. -!- To recycle the disulfide, known atypical 2-Cys Prxs appear to use thioredoxin as an electron donor. -!- The 1-Cys Prxs conserve only the peroxidatic cysteine, so that its oxidized form is directly reduced to cysteine by the reductant molecule.
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UniProtKB Entries (1)
Q9Y9L0 |
TDXH_AERPE
Aeropyrum pernix K1
Peroxiredoxin
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PDB Structure
PDB | 2ZCT |
External Links | |
Method | X-RAY DIFFRACTION |
Organism | |
Primary Citation |
Oxidation of archaeal peroxiredoxin involves a hypervalent sulfur intermediate
Proc.Natl.Acad.Sci.Usa
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