Peroxidase-Cyclooxygenase superfamily (Animal Prxs)

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Last update: 2021-12-02 (Bruno Savelli)

Vertebrate peroxidase : Eosinophil peroxidase (EPO), Lactoperoxidase (LPO), Myeloperoxidase (MPO), Thyroid peroxidase (TPO)
- Non mamalian vertebrate peroxidase (POX), Peroxidasin (Pxd) and Peroxinectin
- Bacterial peroxicin (Pxc) 
- Invertebrate peroxinectin (Pxt)
- Short peroxidockerin (Pxt)
- Alpha-dioxygenase (aDox)
- Dual oxidase (DuOx)
- Prostaglandin H synthase (Cyclooxygenase) (PGHS/CyOx)
- Linoleate diol synthase (PGHS like) (LDS)


Members of this superfamily reduce hydrogen peroxide and oxidise a variety of organic (AH2) and inorganic (X-) substrates according to:
H2O2 + 2 AH2  2 H2O + 2 AH. (Reaction #1)
H2O2 + X- + H+ H2O + HOX (Reaction #2)

Prosthetic heme group of members of this superfamily is covalently linked with the apoprotein. By producing hypohalous acid and hypothiocianate MPO, EPO and LPO participate in unspecific immune defence and TPO in hormone biosynthesis. Numerous representatives are fusion proteins (e.g. Pxd, some Pxt, DuOx) with non-peroxidase domains.

Vertebrate peroxidase
-Eosinophil peroxidase (EPO)
-Lactoperoxidase (LPO)
-Myeloperoxidase (MPO)
-Thyroid peroxidase (TPO)
-Non mamalian vertebrate peroxidase (POX)
-Peroxidasin (Pxd)
-vascular peroxidase Peroxinectin
-Bacterial peroxicin (Pxc): some of the sequence of this group has a BACTERIOCIN function
-Invertebrate peroxinectin (Pxt)
-Short peroxidockerin (PxDo): In addition to the peroxidase, some of the sequence of this group contains a type I dockerin domain (tandem repeat of two calcium-binding loop-helix motifs, distinct from the EF-hand).

Alpha-dioxygenase (DiOx): a-Dioxygenases constitute a family of fatty acid-metabolizing enzymes only detected in plants. THese enzymes catalyze the initial step of the a-oxidation sequence. They protect plant tissues from undergoing excessive necrosis, and their activation is part of the defence mechanisms induced to protect cells from oxidative stress.

Dual oxidase (DuOx) Prostaglandin H synthase (Cyclooxygenase) (PGHS/CyOx) Linoleate diol synthase (PGHS like) (LDS): catalyzes two enzymatic reactions, viz. dioxygenation of linoleic acid into (8R)-hydroperoxylinoleate and isomerization of (8R)-hydroperoxylinoleate into (7S,8S)-dihydroxylinoleate


Pfam: PF00141
Interpro: IPR010255 Haem peroxidase and IPR002007 Haem peroxidase

The profiles do not make a distinction between the different animal peroxidases.

formerly known as animal peroxidase superfamily


Zamocky, M., Jakopitsch, C., Furtmuller, P.G., Dunand, C. and Obinger, C. (2008) The peroxidase-cyclooxygenase superfamily: reconstructed evolution of critical enzymes of the innate immune system. Proteins: Structure, Function, and Bioinformatics 72: 589-605.
Zamocky, M., Hofbauer, S., Schaffner, I., Gasselhuber, B., Nicolussi, A., Soudi, M., Pirker, K.F., Furtmaller, P.G., Obinger, C. (2015) Independent evolution of four heme peroxidase superfamilies. Arch. Biochem. Biophys. 574:108-119.
Daiyasu H, Toh H (2000) Molecular Evolution of the Myeloperoxidase Family J Mol Evol 51: 433-445
Hamberg M, Ponce de Leon I, Rodriguez MJ, Castresana C. Alpha-dioxygenases. Biochem Biophys Res Commun. 2005 Dec 9;338(1):169-74. PMID: 16137659
Hornsten L, Su C, Osbourn AE, Garosi P, Hellman U, Wernstedt C, Oliw EH (1999). Cloning of linoleate diol synthase reveals homology with prostaglandin H synthases. J Biol Chem. 1;274(40):28219-24 10497176