Wikipedia
Myeloblastin
Myeloblastin (, leukocyte proteinase 3, leukocyte proteinase 4, Wegener's granulomatosis autoantigen, proteinase PR-3, proteinase-3, PMNL proteinase) is an enzyme. This enzyme catalyses the following chemical reaction
Hydrolysis of proteins, including elastin, by preferential cleavage: -Ala- > -Val-This enzyme is present in polymorphonuclear leukocyte granules.