Proteinase 3 (PR3)
PRTN3; ACPA; AGP7; C-ANCA; MBT; P29; PRK; Serine Proteinase,Neutrophil,Wegener Granulomatosis Autoantigen; Protease K; Proteinase K; Endopeptidase K
is a serine protease enzyme expressed mainly in neutrophil granulocytes. Its exact role in the function of the neutrophil is unknown but in human neutrophils proteinase 3 contributes to the proteolytic generation of antimicrobial peptides. It is also the epitope of anti-neutrophil cytoplasmic antibodies (ANCAs) of the cANCA (cytoplasmic subtype) class, a type of antibody frequently found in the disease Wegener's granulomatosis.
Proteinase K is commonly used in molecular biology to digest protein and remove contamination from preparations of nucleic acid. Addition of proteinase K to nucleic acid preparations rapidly inactivates nucleases that might otherwise degrade the DNA or RNA during purification.