From Biology-Online Dictionary | Biology-Online Dictionary



Phagocytes that serve as component of the host defense system which is responsible in microbial killing activity against wide range of microorganisms.


Myeloperoxidase generally mediate host defense reactions that abundantly expressed in neutrophils and concealed during activation. It is located in thenucleus and cytoplasm that protects DNA against harmed resulting from oxygen radicals generated during myeloidcell function and maturation.

Myeloperoxidase is an enzyme that encoded MPO gene in human and has heme pigment that causes its green color in neutrophils that forms pus and mucus. It has 15 kDa light chains with two variable heavy chain hurdle to prosthetic heme group that encloses calcium binding site with seven ligands making pyramid conformation of pentagon.

Myeloperoxidase produces hypochloric acid from hydrogen peroxide and chloride anion for the period of neutrophils respiratory rupture and oxidizes tyrosine to tyrosyl radical that are both functional as cytotoxic, thereby it used by neutrophils to eradicate bacteria and other pathogenic organisms.

Myeloperoxidase deficiency is genetically acquired that inclined to immune deficiency. Some studies reveal that myeloperoxidase serves as a predictor for myocardial infarction and provide benefits in cardiac related marker of inflammation.

Gene name: MPO

Protein name: Myeloperoxidase

See also:

Immune system