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ProteinQ420012· pop 23· linked from 134 articles

Myeloperoxidase

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Also known as MPO, uniprot:P05164

Myeloperoxidase (MPO) is a peroxidase enzyme that in humans is encoded by the MPO gene on chromosome 17. MPO is most abundantly expressed in neutrophils (a subtype of white blood cells), and produces hypohalous acids to carry out their antimicrobial activity, including hypochlorous acid, the sodium salt of which is the chemical in bleach. It is a lysosomal protein stored in azurophilic granules of the neutrophil and released into the extracellular space during degranulation. Neutrophil myeloperoxidase has a heme pigment, which causes its green color in secretions rich in neutrophils, such as m

Key facts

Enzyme.Name
Myeloperoxidase
Enzyme.EC_number
1.11.2.2

via Wikipedia infobox

Protein · UniProt

Myeloperoxidase

Gene
MPO
Organism
Homo sapiens (Human)
Length
745 aa
Molecular mass
83,869 Da
Evidence
1: Evidence at protein level

Peroxidase that plays a central role in the host defense system of polymorphonuclear leukocytes by mediating both (1) formation of neutrophil extracellular trap (NETs) and (2) microbicidal activity (PubMed:16125131, PubMed:17438335, PubMed:20974672, PubMed:20974816, PubMed:22131345, PubMed:25066128, PubMed:28574339, PubMed:40963017, PubMed:4978299, PubMed:6295491). Promotes NET formation by mediating chromatin disassembly: translocates to the nucleus and specifically binds to nucleosomes, both as monomer and homodimer, leading to nucleosome unstacking and initial chromatin decondensation (P…

3D-structureAlternative splicingCalciumChromosomeCytoplasmic vesicleDirect protein sequencingDisease variantDisulfide bond
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Swiss-Prot (reviewed) · via UniProt

Wikidata facts

Instance of
protein
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Sources (4)

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~7 min read

Encyclopedic overview

13 sections
Contents
  • Structure
  • Reaction mechanism
  • Function
  • Role in innate immunity
  • Clinical significance
  • Myeloperoxidase deficiency
  • Vasculitis
  • Atherosclerosis and heart disease
  • Medical tests
  • Inhibitors
  • See also
  • References
  • External links

Myeloperoxidase (MPO) is a peroxidase enzyme that in humans is encoded by the MPO gene on chromosome 17. MPO is most abundantly expressed in neutrophils (a subtype of white blood cells), and produces hypohalous acids to carry out their antimicrobial activity, including hypochlorous acid, the sodium salt of which is the chemical in bleach. It is a lysosomal protein stored in azurophilic granules of the neutrophil and released into the extracellular space during degranulation. Neutrophil myeloperoxidase has a heme pigment, which causes its green color in secretions rich in neutrophils, such as mucus and sputum. The green color contributed to its outdated name verdoperoxidase.

Myeloperoxidase is found in many different organisms including mammals, birds, fish, reptiles, and amphibians. Myeloperoxidase deficiency is a well-documented disease among humans resulting in impaired immune function.

Excerpted from Wikipedia’s “Myeloperoxidase” article, available under the CC BY-SA 4.0 licence.